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[bcachefs-tools-debian] / libbcachefs / btree_update_leaf.c
1 // SPDX-License-Identifier: GPL-2.0
2
3 #include "bcachefs.h"
4 #include "btree_update.h"
5 #include "btree_update_interior.h"
6 #include "btree_gc.h"
7 #include "btree_io.h"
8 #include "btree_iter.h"
9 #include "btree_key_cache.h"
10 #include "btree_locking.h"
11 #include "buckets.h"
12 #include "debug.h"
13 #include "error.h"
14 #include "extent_update.h"
15 #include "journal.h"
16 #include "journal_reclaim.h"
17 #include "keylist.h"
18 #include "recovery.h"
19 #include "subvolume.h"
20 #include "replicas.h"
21
22 #include <linux/prefetch.h>
23 #include <linux/sort.h>
24 #include <trace/events/bcachefs.h>
25
26 static int __must_check
27 bch2_trans_update_by_path(struct btree_trans *, struct btree_path *,
28                           struct bkey_i *, enum btree_update_flags);
29
30 static inline int btree_insert_entry_cmp(const struct btree_insert_entry *l,
31                                          const struct btree_insert_entry *r)
32 {
33         return   cmp_int(l->btree_id,   r->btree_id) ?:
34                  -cmp_int(l->level,     r->level) ?:
35                  bpos_cmp(l->k->k.p,    r->k->k.p);
36 }
37
38 static inline struct btree_path_level *insert_l(struct btree_insert_entry *i)
39 {
40         return i->path->l + i->level;
41 }
42
43 static inline bool same_leaf_as_prev(struct btree_trans *trans,
44                                      struct btree_insert_entry *i)
45 {
46         return i != trans->updates &&
47                 insert_l(&i[0])->b == insert_l(&i[-1])->b;
48 }
49
50 static inline bool same_leaf_as_next(struct btree_trans *trans,
51                                      struct btree_insert_entry *i)
52 {
53         return i + 1 < trans->updates + trans->nr_updates &&
54                 insert_l(&i[0])->b == insert_l(&i[1])->b;
55 }
56
57 static inline void bch2_btree_node_prep_for_write(struct btree_trans *trans,
58                                                   struct btree_path *path,
59                                                   struct btree *b)
60 {
61         struct bch_fs *c = trans->c;
62
63         if (path->cached)
64                 return;
65
66         if (unlikely(btree_node_just_written(b)) &&
67             bch2_btree_post_write_cleanup(c, b))
68                 bch2_trans_node_reinit_iter(trans, b);
69
70         /*
71          * If the last bset has been written, or if it's gotten too big - start
72          * a new bset to insert into:
73          */
74         if (want_new_bset(c, b))
75                 bch2_btree_init_next(trans, b);
76 }
77
78 void bch2_btree_node_lock_for_insert(struct btree_trans *trans,
79                                      struct btree_path *path,
80                                      struct btree *b)
81 {
82         bch2_btree_node_lock_write(trans, path, b);
83         bch2_btree_node_prep_for_write(trans, path, b);
84 }
85
86 /* Inserting into a given leaf node (last stage of insert): */
87
88 /* Handle overwrites and do insert, for non extents: */
89 bool bch2_btree_bset_insert_key(struct btree_trans *trans,
90                                 struct btree_path *path,
91                                 struct btree *b,
92                                 struct btree_node_iter *node_iter,
93                                 struct bkey_i *insert)
94 {
95         struct bkey_packed *k;
96         unsigned clobber_u64s = 0, new_u64s = 0;
97
98         EBUG_ON(btree_node_just_written(b));
99         EBUG_ON(bset_written(b, btree_bset_last(b)));
100         EBUG_ON(bkey_deleted(&insert->k) && bkey_val_u64s(&insert->k));
101         EBUG_ON(bpos_cmp(insert->k.p, b->data->min_key) < 0);
102         EBUG_ON(bpos_cmp(insert->k.p, b->data->max_key) > 0);
103         EBUG_ON(insert->k.u64s >
104                 bch_btree_keys_u64s_remaining(trans->c, b));
105
106         k = bch2_btree_node_iter_peek_all(node_iter, b);
107         if (k && bkey_cmp_left_packed(b, k, &insert->k.p))
108                 k = NULL;
109
110         /* @k is the key being overwritten/deleted, if any: */
111         EBUG_ON(k && bkey_deleted(k));
112
113         /* Deleting, but not found? nothing to do: */
114         if (bkey_deleted(&insert->k) && !k)
115                 return false;
116
117         if (bkey_deleted(&insert->k)) {
118                 /* Deleting: */
119                 btree_account_key_drop(b, k);
120                 k->type = KEY_TYPE_deleted;
121
122                 if (k->needs_whiteout)
123                         push_whiteout(trans->c, b, insert->k.p);
124                 k->needs_whiteout = false;
125
126                 if (k >= btree_bset_last(b)->start) {
127                         clobber_u64s = k->u64s;
128                         bch2_bset_delete(b, k, clobber_u64s);
129                         goto fix_iter;
130                 } else {
131                         bch2_btree_path_fix_key_modified(trans, b, k);
132                 }
133
134                 return true;
135         }
136
137         if (k) {
138                 /* Overwriting: */
139                 btree_account_key_drop(b, k);
140                 k->type = KEY_TYPE_deleted;
141
142                 insert->k.needs_whiteout = k->needs_whiteout;
143                 k->needs_whiteout = false;
144
145                 if (k >= btree_bset_last(b)->start) {
146                         clobber_u64s = k->u64s;
147                         goto overwrite;
148                 } else {
149                         bch2_btree_path_fix_key_modified(trans, b, k);
150                 }
151         }
152
153         k = bch2_btree_node_iter_bset_pos(node_iter, b, bset_tree_last(b));
154 overwrite:
155         bch2_bset_insert(b, node_iter, k, insert, clobber_u64s);
156         new_u64s = k->u64s;
157 fix_iter:
158         if (clobber_u64s != new_u64s)
159                 bch2_btree_node_iter_fix(trans, path, b, node_iter, k,
160                                          clobber_u64s, new_u64s);
161         return true;
162 }
163
164 static int __btree_node_flush(struct journal *j, struct journal_entry_pin *pin,
165                                unsigned i, u64 seq)
166 {
167         struct bch_fs *c = container_of(j, struct bch_fs, journal);
168         struct btree_write *w = container_of(pin, struct btree_write, journal);
169         struct btree *b = container_of(w, struct btree, writes[i]);
170
171         btree_node_lock_type(c, b, SIX_LOCK_read);
172         bch2_btree_node_write_cond(c, b,
173                 (btree_current_write(b) == w && w->journal.seq == seq));
174         six_unlock_read(&b->c.lock);
175         return 0;
176 }
177
178 static int btree_node_flush0(struct journal *j, struct journal_entry_pin *pin, u64 seq)
179 {
180         return __btree_node_flush(j, pin, 0, seq);
181 }
182
183 static int btree_node_flush1(struct journal *j, struct journal_entry_pin *pin, u64 seq)
184 {
185         return __btree_node_flush(j, pin, 1, seq);
186 }
187
188 inline void bch2_btree_add_journal_pin(struct bch_fs *c,
189                                        struct btree *b, u64 seq)
190 {
191         struct btree_write *w = btree_current_write(b);
192
193         bch2_journal_pin_add(&c->journal, seq, &w->journal,
194                              btree_node_write_idx(b) == 0
195                              ? btree_node_flush0
196                              : btree_node_flush1);
197 }
198
199 /**
200  * btree_insert_key - insert a key one key into a leaf node
201  */
202 static bool btree_insert_key_leaf(struct btree_trans *trans,
203                                   struct btree_insert_entry *insert)
204 {
205         struct bch_fs *c = trans->c;
206         struct btree *b = insert_l(insert)->b;
207         struct bset_tree *t = bset_tree_last(b);
208         struct bset *i = bset(b, t);
209         int old_u64s = bset_u64s(t);
210         int old_live_u64s = b->nr.live_u64s;
211         int live_u64s_added, u64s_added;
212
213         if (unlikely(!bch2_btree_bset_insert_key(trans, insert->path, b,
214                                         &insert_l(insert)->iter, insert->k)))
215                 return false;
216
217         i->journal_seq = cpu_to_le64(max(trans->journal_res.seq,
218                                          le64_to_cpu(i->journal_seq)));
219
220         bch2_btree_add_journal_pin(c, b, trans->journal_res.seq);
221
222         if (unlikely(!btree_node_dirty(b)))
223                 set_btree_node_dirty(c, b);
224
225         live_u64s_added = (int) b->nr.live_u64s - old_live_u64s;
226         u64s_added = (int) bset_u64s(t) - old_u64s;
227
228         if (b->sib_u64s[0] != U16_MAX && live_u64s_added < 0)
229                 b->sib_u64s[0] = max(0, (int) b->sib_u64s[0] + live_u64s_added);
230         if (b->sib_u64s[1] != U16_MAX && live_u64s_added < 0)
231                 b->sib_u64s[1] = max(0, (int) b->sib_u64s[1] + live_u64s_added);
232
233         if (u64s_added > live_u64s_added &&
234             bch2_maybe_compact_whiteouts(c, b))
235                 bch2_trans_node_reinit_iter(trans, b);
236
237         return true;
238 }
239
240 /* Cached btree updates: */
241
242 /* Normal update interface: */
243
244 static inline void btree_insert_entry_checks(struct btree_trans *trans,
245                                              struct btree_insert_entry *i)
246 {
247         BUG_ON(bpos_cmp(i->k->k.p, i->path->pos));
248         BUG_ON(i->cached        != i->path->cached);
249         BUG_ON(i->level         != i->path->level);
250         BUG_ON(i->btree_id      != i->path->btree_id);
251         EBUG_ON(!i->level &&
252                 !(i->flags & BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE) &&
253                 test_bit(JOURNAL_REPLAY_DONE, &trans->c->journal.flags) &&
254                 i->k->k.p.snapshot &&
255                 bch2_snapshot_internal_node(trans->c, i->k->k.p.snapshot));
256 }
257
258 static noinline int
259 bch2_trans_journal_preres_get_cold(struct btree_trans *trans, unsigned u64s,
260                                    unsigned long trace_ip)
261 {
262         struct bch_fs *c = trans->c;
263         int ret;
264
265         bch2_trans_unlock(trans);
266
267         ret = bch2_journal_preres_get(&c->journal,
268                         &trans->journal_preres, u64s, 0);
269         if (ret)
270                 return ret;
271
272         if (!bch2_trans_relock(trans)) {
273                 trace_trans_restart_journal_preres_get(trans->fn, trace_ip);
274                 return -EINTR;
275         }
276
277         return 0;
278 }
279
280 static inline int bch2_trans_journal_res_get(struct btree_trans *trans,
281                                              unsigned flags)
282 {
283         struct bch_fs *c = trans->c;
284         int ret;
285
286         if (trans->flags & BTREE_INSERT_JOURNAL_RESERVED)
287                 flags |= JOURNAL_RES_GET_RESERVED;
288
289         ret = bch2_journal_res_get(&c->journal, &trans->journal_res,
290                                    trans->journal_u64s, flags);
291
292         return ret == -EAGAIN ? BTREE_INSERT_NEED_JOURNAL_RES : ret;
293 }
294
295 #define JSET_ENTRY_LOG_U64s             4
296
297 static noinline void journal_transaction_name(struct btree_trans *trans)
298 {
299         struct bch_fs *c = trans->c;
300         struct jset_entry *entry = journal_res_entry(&c->journal, &trans->journal_res);
301         struct jset_entry_log *l = container_of(entry, struct jset_entry_log, entry);
302         unsigned u64s = JSET_ENTRY_LOG_U64s - 1;
303         unsigned b, buflen = u64s * sizeof(u64);
304
305         l->entry.u64s           = cpu_to_le16(u64s);
306         l->entry.btree_id       = 0;
307         l->entry.level          = 0;
308         l->entry.type           = BCH_JSET_ENTRY_log;
309         l->entry.pad[0]         = 0;
310         l->entry.pad[1]         = 0;
311         l->entry.pad[2]         = 0;
312         b = min_t(unsigned, strlen(trans->fn), buflen);
313         memcpy(l->d, trans->fn, b);
314         while (b < buflen)
315                 l->d[b++] = '\0';
316
317         trans->journal_res.offset       += JSET_ENTRY_LOG_U64s;
318         trans->journal_res.u64s         -= JSET_ENTRY_LOG_U64s;
319 }
320
321 static inline enum btree_insert_ret
322 btree_key_can_insert(struct btree_trans *trans,
323                      struct btree *b,
324                      unsigned u64s)
325 {
326         struct bch_fs *c = trans->c;
327
328         if (!bch2_btree_node_insert_fits(c, b, u64s))
329                 return BTREE_INSERT_BTREE_NODE_FULL;
330
331         return BTREE_INSERT_OK;
332 }
333
334 static enum btree_insert_ret
335 btree_key_can_insert_cached(struct btree_trans *trans,
336                             struct btree_path *path,
337                             unsigned u64s)
338 {
339         struct bch_fs *c = trans->c;
340         struct bkey_cached *ck = (void *) path->l[0].b;
341         unsigned new_u64s;
342         struct bkey_i *new_k;
343
344         EBUG_ON(path->level);
345
346         if (!test_bit(BKEY_CACHED_DIRTY, &ck->flags) &&
347             bch2_btree_key_cache_must_wait(c) &&
348             !(trans->flags & BTREE_INSERT_JOURNAL_RECLAIM))
349                 return BTREE_INSERT_NEED_JOURNAL_RECLAIM;
350
351         /*
352          * bch2_varint_decode can read past the end of the buffer by at most 7
353          * bytes (it won't be used):
354          */
355         u64s += 1;
356
357         if (u64s <= ck->u64s)
358                 return BTREE_INSERT_OK;
359
360         new_u64s        = roundup_pow_of_two(u64s);
361         new_k           = krealloc(ck->k, new_u64s * sizeof(u64), GFP_NOFS);
362         if (!new_k) {
363                 bch_err(c, "error allocating memory for key cache key, btree %s u64s %u",
364                         bch2_btree_ids[path->btree_id], new_u64s);
365                 return -ENOMEM;
366         }
367
368         ck->u64s        = new_u64s;
369         ck->k           = new_k;
370         return BTREE_INSERT_OK;
371 }
372
373 static inline void do_btree_insert_one(struct btree_trans *trans,
374                                        struct btree_insert_entry *i)
375 {
376         struct bch_fs *c = trans->c;
377         struct journal *j = &c->journal;
378         bool did_work;
379
380         EBUG_ON(trans->journal_res.ref !=
381                 !(trans->flags & BTREE_INSERT_JOURNAL_REPLAY));
382
383         i->k->k.needs_whiteout = false;
384
385         did_work = !i->cached
386                 ? btree_insert_key_leaf(trans, i)
387                 : bch2_btree_insert_key_cached(trans, i->path, i->k);
388         if (!did_work)
389                 return;
390
391         if (likely(!(trans->flags & BTREE_INSERT_JOURNAL_REPLAY))) {
392                 bch2_journal_add_keys(j, &trans->journal_res,
393                                       i->btree_id,
394                                       i->level,
395                                       i->k);
396
397                 if (trans->journal_seq)
398                         *trans->journal_seq = trans->journal_res.seq;
399         }
400 }
401
402 static noinline int bch2_trans_mark_gc(struct btree_trans *trans)
403 {
404         struct bch_fs *c = trans->c;
405         struct btree_insert_entry *i;
406         int ret = 0;
407
408         trans_for_each_update(trans, i) {
409                 /*
410                  * XXX: synchronization of cached update triggers with gc
411                  * XXX: synchronization of interior node updates with gc
412                  */
413                 BUG_ON(i->cached || i->level);
414
415                 if (gc_visited(c, gc_pos_btree_node(insert_l(i)->b))) {
416                         ret = bch2_mark_update(trans, i->path, i->k,
417                                                i->flags|BTREE_TRIGGER_GC);
418                         if (ret)
419                                 break;
420                 }
421         }
422
423         return ret;
424 }
425
426 static inline int
427 bch2_trans_commit_write_locked(struct btree_trans *trans,
428                                struct btree_insert_entry **stopped_at,
429                                unsigned long trace_ip)
430 {
431         struct bch_fs *c = trans->c;
432         struct btree_insert_entry *i;
433         struct btree_trans_commit_hook *h;
434         unsigned u64s = 0;
435         bool marking = false;
436         int ret;
437
438         if (race_fault()) {
439                 trace_trans_restart_fault_inject(trans->fn, trace_ip);
440                 trans->restarted = true;
441                 return -EINTR;
442         }
443
444         /*
445          * Check if the insert will fit in the leaf node with the write lock
446          * held, otherwise another thread could write the node changing the
447          * amount of space available:
448          */
449
450         prefetch(&trans->c->journal.flags);
451
452         h = trans->hooks;
453         while (h) {
454                 ret = h->fn(trans, h);
455                 if (ret)
456                         return ret;
457                 h = h->next;
458         }
459
460         trans_for_each_update(trans, i) {
461                 /* Multiple inserts might go to same leaf: */
462                 if (!same_leaf_as_prev(trans, i))
463                         u64s = 0;
464
465                 u64s += i->k->k.u64s;
466                 ret = !i->cached
467                         ? btree_key_can_insert(trans, insert_l(i)->b, u64s)
468                         : btree_key_can_insert_cached(trans, i->path, u64s);
469                 if (ret) {
470                         *stopped_at = i;
471                         return ret;
472                 }
473
474                 if (btree_node_type_needs_gc(i->bkey_type))
475                         marking = true;
476         }
477
478         /*
479          * Don't get journal reservation until after we know insert will
480          * succeed:
481          */
482         if (likely(!(trans->flags & BTREE_INSERT_JOURNAL_REPLAY))) {
483                 ret = bch2_trans_journal_res_get(trans,
484                                 JOURNAL_RES_GET_NONBLOCK);
485                 if (ret)
486                         return ret;
487
488                 if (unlikely(trans->journal_transaction_names))
489                         journal_transaction_name(trans);
490         } else {
491                 trans->journal_res.seq = c->journal.replay_journal_seq;
492         }
493
494         if (unlikely(trans->extra_journal_entry_u64s)) {
495                 memcpy_u64s_small(journal_res_entry(&c->journal, &trans->journal_res),
496                                   trans->extra_journal_entries,
497                                   trans->extra_journal_entry_u64s);
498
499                 trans->journal_res.offset       += trans->extra_journal_entry_u64s;
500                 trans->journal_res.u64s         -= trans->extra_journal_entry_u64s;
501         }
502
503         /*
504          * Not allowed to fail after we've gotten our journal reservation - we
505          * have to use it:
506          */
507
508         if (!(trans->flags & BTREE_INSERT_JOURNAL_REPLAY)) {
509                 if (bch2_journal_seq_verify)
510                         trans_for_each_update(trans, i)
511                                 i->k->k.version.lo = trans->journal_res.seq;
512                 else if (bch2_inject_invalid_keys)
513                         trans_for_each_update(trans, i)
514                                 i->k->k.version = MAX_VERSION;
515         }
516
517         if (trans->fs_usage_deltas &&
518             bch2_trans_fs_usage_apply(trans, trans->fs_usage_deltas))
519                 return BTREE_INSERT_NEED_MARK_REPLICAS;
520
521         trans_for_each_update(trans, i)
522                 if (BTREE_NODE_TYPE_HAS_MEM_TRIGGERS & (1U << i->bkey_type)) {
523                         ret = bch2_mark_update(trans, i->path, i->k, i->flags);
524                         if (ret)
525                                 return ret;
526                 }
527
528         if (unlikely(c->gc_pos.phase)) {
529                 ret = bch2_trans_mark_gc(trans);
530                 if  (ret)
531                         return ret;
532         }
533
534         trans_for_each_update(trans, i)
535                 do_btree_insert_one(trans, i);
536
537         return ret;
538 }
539
540 static inline void path_upgrade_readers(struct btree_trans *trans, struct btree_path *path)
541 {
542         unsigned l;
543
544         for (l = 0; l < BTREE_MAX_DEPTH; l++)
545                 if (btree_node_read_locked(path, l))
546                         BUG_ON(!bch2_btree_node_upgrade(trans, path, l));
547 }
548
549 static inline void upgrade_readers(struct btree_trans *trans, struct btree_path *path)
550 {
551         struct btree *b = path_l(path)->b;
552
553         do {
554                 if (path->nodes_locked &&
555                     path->nodes_locked != path->nodes_intent_locked)
556                         path_upgrade_readers(trans, path);
557         } while ((path = prev_btree_path(trans, path)) &&
558                  path_l(path)->b == b);
559 }
560
561 /*
562  * Check for nodes that we have both read and intent locks on, and upgrade the
563  * readers to intent:
564  */
565 static inline void normalize_read_intent_locks(struct btree_trans *trans)
566 {
567         struct btree_path *path;
568         unsigned i, nr_read = 0, nr_intent = 0;
569
570         trans_for_each_path_inorder(trans, path, i) {
571                 struct btree_path *next = i + 1 < trans->nr_sorted
572                         ? trans->paths + trans->sorted[i + 1]
573                         : NULL;
574
575                 if (path->nodes_locked) {
576                         if (path->nodes_intent_locked)
577                                 nr_intent++;
578                         else
579                                 nr_read++;
580                 }
581
582                 if (!next || path_l(path)->b != path_l(next)->b) {
583                         if (nr_read && nr_intent)
584                                 upgrade_readers(trans, path);
585
586                         nr_read = nr_intent = 0;
587                 }
588         }
589
590         bch2_trans_verify_locks(trans);
591 }
592
593 static inline bool have_conflicting_read_lock(struct btree_trans *trans, struct btree_path *pos)
594 {
595         struct btree_path *path;
596         unsigned i;
597
598         trans_for_each_path_inorder(trans, path, i) {
599                 //if (path == pos)
600                 //      break;
601
602                 if (path->nodes_locked != path->nodes_intent_locked &&
603                     !bch2_btree_path_upgrade(trans, path, path->level + 1))
604                         return true;
605         }
606
607         return false;
608 }
609
610 static inline int trans_lock_write(struct btree_trans *trans)
611 {
612         struct btree_insert_entry *i;
613
614         trans_for_each_update(trans, i) {
615                 if (same_leaf_as_prev(trans, i))
616                         continue;
617
618                 if (!six_trylock_write(&insert_l(i)->b->c.lock)) {
619                         if (have_conflicting_read_lock(trans, i->path))
620                                 goto fail;
621
622                         __btree_node_lock_type(trans->c, insert_l(i)->b,
623                                                SIX_LOCK_write);
624                 }
625
626                 bch2_btree_node_prep_for_write(trans, i->path, insert_l(i)->b);
627         }
628
629         return 0;
630 fail:
631         while (--i >= trans->updates) {
632                 if (same_leaf_as_prev(trans, i))
633                         continue;
634
635                 bch2_btree_node_unlock_write_inlined(trans, i->path, insert_l(i)->b);
636         }
637
638         trace_trans_restart_would_deadlock_write(trans->fn);
639         return btree_trans_restart(trans);
640 }
641
642 static noinline void bch2_drop_overwrites_from_journal(struct btree_trans *trans)
643 {
644         struct btree_insert_entry *i;
645
646         trans_for_each_update(trans, i)
647                 bch2_journal_key_overwritten(trans->c, i->btree_id, i->level, i->k->k.p);
648 }
649
650 /*
651  * Get journal reservation, take write locks, and attempt to do btree update(s):
652  */
653 static inline int do_bch2_trans_commit(struct btree_trans *trans,
654                                        struct btree_insert_entry **stopped_at,
655                                        unsigned long trace_ip)
656 {
657         struct bch_fs *c = trans->c;
658         struct btree_insert_entry *i;
659         struct bkey_s_c old;
660         int ret, u64s_delta = 0;
661
662         trans_for_each_update(trans, i) {
663                 const char *invalid = bch2_bkey_invalid(c,
664                                 bkey_i_to_s_c(i->k), i->bkey_type);
665                 if (invalid) {
666                         char buf[200];
667
668                         bch2_bkey_val_to_text(&PBUF(buf), c, bkey_i_to_s_c(i->k));
669                         bch2_fs_fatal_error(c, "invalid bkey %s on insert from %s -> %ps: %s\n",
670                                             buf, trans->fn, (void *) i->ip_allocated, invalid);
671                         return -EINVAL;
672                 }
673                 btree_insert_entry_checks(trans, i);
674         }
675
676         trans_for_each_update(trans, i) {
677                 struct bkey u;
678
679                 /*
680                  * peek_slot() doesn't yet work on iterators that point to
681                  * interior nodes:
682                  */
683                 if (i->cached || i->level)
684                         continue;
685
686                 old = bch2_btree_path_peek_slot(i->path, &u);
687                 ret = bkey_err(old);
688                 if (unlikely(ret))
689                         return ret;
690
691                 u64s_delta += !bkey_deleted(&i->k->k) ? i->k->k.u64s : 0;
692                 u64s_delta -= !bkey_deleted(old.k) ? old.k->u64s : 0;
693
694                 if (!same_leaf_as_next(trans, i)) {
695                         if (u64s_delta <= 0) {
696                                 ret = bch2_foreground_maybe_merge(trans, i->path,
697                                                         i->level, trans->flags);
698                                 if (unlikely(ret))
699                                         return ret;
700                         }
701
702                         u64s_delta = 0;
703                 }
704         }
705
706         ret = bch2_journal_preres_get(&c->journal,
707                         &trans->journal_preres, trans->journal_preres_u64s,
708                         JOURNAL_RES_GET_NONBLOCK|
709                         ((trans->flags & BTREE_INSERT_JOURNAL_RESERVED)
710                          ? JOURNAL_RES_GET_RESERVED : 0));
711         if (unlikely(ret == -EAGAIN))
712                 ret = bch2_trans_journal_preres_get_cold(trans,
713                                                 trans->journal_preres_u64s, trace_ip);
714         if (unlikely(ret))
715                 return ret;
716
717         normalize_read_intent_locks(trans);
718
719         ret = trans_lock_write(trans);
720         if (unlikely(ret))
721                 return ret;
722
723         ret = bch2_trans_commit_write_locked(trans, stopped_at, trace_ip);
724
725         if (!ret && unlikely(!test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags)))
726                 bch2_drop_overwrites_from_journal(trans);
727
728         trans_for_each_update(trans, i)
729                 if (!same_leaf_as_prev(trans, i))
730                         bch2_btree_node_unlock_write_inlined(trans, i->path,
731                                                         insert_l(i)->b);
732
733         if (!ret && trans->journal_pin)
734                 bch2_journal_pin_add(&c->journal, trans->journal_res.seq,
735                                      trans->journal_pin, NULL);
736
737         /*
738          * Drop journal reservation after dropping write locks, since dropping
739          * the journal reservation may kick off a journal write:
740          */
741         bch2_journal_res_put(&c->journal, &trans->journal_res);
742
743         if (unlikely(ret))
744                 return ret;
745
746         bch2_trans_downgrade(trans);
747
748         return 0;
749 }
750
751 static int journal_reclaim_wait_done(struct bch_fs *c)
752 {
753         int ret = bch2_journal_error(&c->journal) ?:
754                 !bch2_btree_key_cache_must_wait(c);
755
756         if (!ret)
757                 journal_reclaim_kick(&c->journal);
758         return ret;
759 }
760
761 static noinline
762 int bch2_trans_commit_error(struct btree_trans *trans,
763                             struct btree_insert_entry *i,
764                             int ret, unsigned long trace_ip)
765 {
766         struct bch_fs *c = trans->c;
767
768         switch (ret) {
769         case BTREE_INSERT_BTREE_NODE_FULL:
770                 ret = bch2_btree_split_leaf(trans, i->path, trans->flags);
771                 if (!ret)
772                         return 0;
773
774                 if (ret == -EINTR)
775                         trace_trans_restart_btree_node_split(trans->fn, trace_ip,
776                                                 i->btree_id, &i->path->pos);
777                 break;
778         case BTREE_INSERT_NEED_MARK_REPLICAS:
779                 bch2_trans_unlock(trans);
780
781                 ret = bch2_replicas_delta_list_mark(c, trans->fs_usage_deltas);
782                 if (ret)
783                         break;
784
785                 if (bch2_trans_relock(trans))
786                         return 0;
787
788                 trace_trans_restart_mark_replicas(trans->fn, trace_ip);
789                 ret = -EINTR;
790                 break;
791         case BTREE_INSERT_NEED_JOURNAL_RES:
792                 bch2_trans_unlock(trans);
793
794                 if ((trans->flags & BTREE_INSERT_JOURNAL_RECLAIM) &&
795                     !(trans->flags & BTREE_INSERT_JOURNAL_RESERVED)) {
796                         trans->restarted = true;
797                         ret = -EAGAIN;
798                         break;
799                 }
800
801                 ret = bch2_trans_journal_res_get(trans, JOURNAL_RES_GET_CHECK);
802                 if (ret)
803                         break;
804
805                 if (bch2_trans_relock(trans))
806                         return 0;
807
808                 trace_trans_restart_journal_res_get(trans->fn, trace_ip);
809                 ret = -EINTR;
810                 break;
811         case BTREE_INSERT_NEED_JOURNAL_RECLAIM:
812                 bch2_trans_unlock(trans);
813
814                 trace_trans_blocked_journal_reclaim(trans->fn, trace_ip);
815
816                 wait_event_freezable(c->journal.reclaim_wait,
817                                      (ret = journal_reclaim_wait_done(c)));
818                 if (ret < 0)
819                         break;
820
821                 if (bch2_trans_relock(trans))
822                         return 0;
823
824                 trace_trans_restart_journal_reclaim(trans->fn, trace_ip);
825                 ret = -EINTR;
826                 break;
827         default:
828                 BUG_ON(ret >= 0);
829                 break;
830         }
831
832         BUG_ON((ret == EINTR || ret == -EAGAIN) && !trans->restarted);
833         BUG_ON(ret == -ENOSPC &&
834                !(trans->flags & BTREE_INSERT_NOWAIT) &&
835                (trans->flags & BTREE_INSERT_NOFAIL));
836
837         return ret;
838 }
839
840 static noinline int
841 bch2_trans_commit_get_rw_cold(struct btree_trans *trans)
842 {
843         struct bch_fs *c = trans->c;
844         int ret;
845
846         if (likely(!(trans->flags & BTREE_INSERT_LAZY_RW)) ||
847             test_bit(BCH_FS_STARTED, &c->flags))
848                 return -EROFS;
849
850         bch2_trans_unlock(trans);
851
852         ret = bch2_fs_read_write_early(c);
853         if (ret)
854                 return ret;
855
856         if (!bch2_trans_relock(trans))
857                 return -EINTR;
858
859         percpu_ref_get(&c->writes);
860         return 0;
861 }
862
863 static int run_one_trigger(struct btree_trans *trans, struct btree_insert_entry *i,
864                            bool overwrite)
865 {
866         struct bkey             _deleted = KEY(0, 0, 0);
867         struct bkey_s_c         deleted = (struct bkey_s_c) { &_deleted, NULL };
868         struct bkey_s_c         old;
869         struct bkey             unpacked;
870         int ret = 0;
871
872         if ((i->flags & BTREE_TRIGGER_NORUN) ||
873             !(BTREE_NODE_TYPE_HAS_TRANS_TRIGGERS & (1U << i->bkey_type)))
874                 return 0;
875
876         if (!overwrite) {
877                 if (i->insert_trigger_run)
878                         return 0;
879
880                 BUG_ON(i->overwrite_trigger_run);
881                 i->insert_trigger_run = true;
882         } else {
883                 if (i->overwrite_trigger_run)
884                         return 0;
885
886                 BUG_ON(!i->insert_trigger_run);
887                 i->overwrite_trigger_run = true;
888         }
889
890         old = bch2_btree_path_peek_slot(i->path, &unpacked);
891         _deleted.p = i->path->pos;
892
893         if (overwrite) {
894                 ret = bch2_trans_mark_key(trans, old, deleted,
895                                 BTREE_TRIGGER_OVERWRITE|i->flags);
896         } else if (old.k->type == i->k->k.type &&
897             ((1U << old.k->type) & BTREE_TRIGGER_WANTS_OLD_AND_NEW)) {
898                 i->overwrite_trigger_run = true;
899                 ret = bch2_trans_mark_key(trans, old, bkey_i_to_s_c(i->k),
900                                 BTREE_TRIGGER_INSERT|BTREE_TRIGGER_OVERWRITE|i->flags);
901         } else {
902                 ret = bch2_trans_mark_key(trans, deleted, bkey_i_to_s_c(i->k),
903                                 BTREE_TRIGGER_INSERT|i->flags);
904         }
905
906         if (ret == -EINTR)
907                 trace_trans_restart_mark(trans->fn, _RET_IP_,
908                                          i->btree_id, &i->path->pos);
909         return ret ?: 1;
910 }
911
912 static int run_btree_triggers(struct btree_trans *trans, enum btree_id btree_id,
913                               struct btree_insert_entry *btree_id_start)
914 {
915         struct btree_insert_entry *i;
916         bool trans_trigger_run;
917         int ret, overwrite;
918
919         for (overwrite = 0; overwrite < 2; overwrite++) {
920
921                 /*
922                  * Running triggers will append more updates to the list of updates as
923                  * we're walking it:
924                  */
925                 do {
926                         trans_trigger_run = false;
927
928                         for (i = btree_id_start;
929                              i < trans->updates + trans->nr_updates && i->btree_id <= btree_id;
930                              i++) {
931                                 ret = run_one_trigger(trans, i, overwrite);
932                                 if (ret < 0)
933                                         return ret;
934                                 if (ret)
935                                         trans_trigger_run = true;
936                         }
937                 } while (trans_trigger_run);
938         }
939
940         return 0;
941 }
942
943 static int bch2_trans_commit_run_triggers(struct btree_trans *trans)
944 {
945         struct btree_insert_entry *i = NULL, *btree_id_start = trans->updates;
946         unsigned btree_id = 0;
947         int ret = 0;
948
949         /*
950          *
951          * For a given btree, this algorithm runs insert triggers before
952          * overwrite triggers: this is so that when extents are being moved
953          * (e.g. by FALLOCATE_FL_INSERT_RANGE), we don't drop references before
954          * they are re-added.
955          */
956         for (btree_id = 0; btree_id < BTREE_ID_NR; btree_id++) {
957                 while (btree_id_start < trans->updates + trans->nr_updates &&
958                        btree_id_start->btree_id < btree_id)
959                         btree_id_start++;
960
961                 ret = run_btree_triggers(trans, btree_id, btree_id_start);
962                 if (ret)
963                         return ret;
964         }
965
966         trans_for_each_update(trans, i)
967                 BUG_ON(!(i->flags & BTREE_TRIGGER_NORUN) &&
968                        (BTREE_NODE_TYPE_HAS_TRANS_TRIGGERS & (1U << i->bkey_type)) &&
969                        (!i->insert_trigger_run || !i->overwrite_trigger_run));
970
971         return 0;
972 }
973
974 int __bch2_trans_commit(struct btree_trans *trans)
975 {
976         struct bch_fs *c = trans->c;
977         struct btree_insert_entry *i = NULL;
978         unsigned u64s;
979         int ret = 0;
980
981         if (!trans->nr_updates &&
982             !trans->extra_journal_entry_u64s)
983                 goto out_reset;
984
985         if (trans->flags & BTREE_INSERT_GC_LOCK_HELD)
986                 lockdep_assert_held(&c->gc_lock);
987
988         memset(&trans->journal_preres, 0, sizeof(trans->journal_preres));
989
990         trans->journal_u64s             = trans->extra_journal_entry_u64s;
991         trans->journal_preres_u64s      = 0;
992
993         trans->journal_transaction_names = READ_ONCE(c->opts.journal_transaction_names);
994
995         if (trans->journal_transaction_names)
996                 trans->journal_u64s += JSET_ENTRY_LOG_U64s;
997
998         if (!(trans->flags & BTREE_INSERT_NOCHECK_RW) &&
999             unlikely(!percpu_ref_tryget(&c->writes))) {
1000                 ret = bch2_trans_commit_get_rw_cold(trans);
1001                 if (ret)
1002                         goto out_reset;
1003         }
1004
1005 #ifdef CONFIG_BCACHEFS_DEBUG
1006         /*
1007          * if BTREE_TRIGGER_NORUN is set, it means we're probably being called
1008          * from the key cache flush code:
1009          */
1010         trans_for_each_update(trans, i)
1011                 if (!i->cached &&
1012                     !(i->flags & BTREE_TRIGGER_NORUN))
1013                         bch2_btree_key_cache_verify_clean(trans,
1014                                         i->btree_id, i->k->k.p);
1015 #endif
1016
1017         ret = bch2_trans_commit_run_triggers(trans);
1018         if (ret)
1019                 goto out;
1020
1021         trans_for_each_update(trans, i) {
1022                 BUG_ON(!i->path->should_be_locked);
1023
1024                 if (unlikely(!bch2_btree_path_upgrade(trans, i->path, i->level + 1))) {
1025                         trace_trans_restart_upgrade(trans->fn, _RET_IP_,
1026                                                     i->btree_id, &i->path->pos);
1027                         ret = btree_trans_restart(trans);
1028                         goto out;
1029                 }
1030
1031                 BUG_ON(!btree_node_intent_locked(i->path, i->level));
1032
1033                 u64s = jset_u64s(i->k->k.u64s);
1034                 if (i->cached &&
1035                     likely(!(trans->flags & BTREE_INSERT_JOURNAL_REPLAY)))
1036                         trans->journal_preres_u64s += u64s;
1037                 trans->journal_u64s += u64s;
1038         }
1039
1040         if (trans->extra_journal_res) {
1041                 ret = bch2_disk_reservation_add(c, trans->disk_res,
1042                                 trans->extra_journal_res,
1043                                 (trans->flags & BTREE_INSERT_NOFAIL)
1044                                 ? BCH_DISK_RESERVATION_NOFAIL : 0);
1045                 if (ret)
1046                         goto err;
1047         }
1048 retry:
1049         BUG_ON(trans->restarted);
1050         memset(&trans->journal_res, 0, sizeof(trans->journal_res));
1051
1052         ret = do_bch2_trans_commit(trans, &i, _RET_IP_);
1053
1054         /* make sure we didn't drop or screw up locks: */
1055         bch2_trans_verify_locks(trans);
1056
1057         if (ret)
1058                 goto err;
1059 out:
1060         bch2_journal_preres_put(&c->journal, &trans->journal_preres);
1061
1062         if (likely(!(trans->flags & BTREE_INSERT_NOCHECK_RW)))
1063                 percpu_ref_put(&c->writes);
1064 out_reset:
1065         trans_for_each_update(trans, i)
1066                 bch2_path_put(trans, i->path, true);
1067
1068         trans->extra_journal_res        = 0;
1069         trans->nr_updates               = 0;
1070         trans->hooks                    = NULL;
1071         trans->extra_journal_entries    = NULL;
1072         trans->extra_journal_entry_u64s = 0;
1073
1074         if (trans->fs_usage_deltas) {
1075                 trans->fs_usage_deltas->used = 0;
1076                 memset(&trans->fs_usage_deltas->memset_start, 0,
1077                        (void *) &trans->fs_usage_deltas->memset_end -
1078                        (void *) &trans->fs_usage_deltas->memset_start);
1079         }
1080
1081         return ret;
1082 err:
1083         ret = bch2_trans_commit_error(trans, i, ret, _RET_IP_);
1084         if (ret)
1085                 goto out;
1086
1087         goto retry;
1088 }
1089
1090 static int check_pos_snapshot_overwritten(struct btree_trans *trans,
1091                                           enum btree_id id,
1092                                           struct bpos pos)
1093 {
1094         struct bch_fs *c = trans->c;
1095         struct btree_iter iter;
1096         struct bkey_s_c k;
1097         int ret;
1098
1099         if (!btree_type_has_snapshots(id))
1100                 return 0;
1101
1102         if (!snapshot_t(c, pos.snapshot)->children[0])
1103                 return 0;
1104
1105         bch2_trans_iter_init(trans, &iter, id, pos,
1106                              BTREE_ITER_NOT_EXTENTS|
1107                              BTREE_ITER_ALL_SNAPSHOTS);
1108         while (1) {
1109                 k = bch2_btree_iter_prev(&iter);
1110                 ret = bkey_err(k);
1111                 if (ret)
1112                         break;
1113
1114                 if (!k.k)
1115                         break;
1116
1117                 if (bkey_cmp(pos, k.k->p))
1118                         break;
1119
1120                 if (bch2_snapshot_is_ancestor(c, k.k->p.snapshot, pos.snapshot)) {
1121                         ret = 1;
1122                         break;
1123                 }
1124         }
1125         bch2_trans_iter_exit(trans, &iter);
1126
1127         return ret;
1128 }
1129
1130 int bch2_trans_update_extent(struct btree_trans *trans,
1131                              struct btree_iter *orig_iter,
1132                              struct bkey_i *insert,
1133                              enum btree_update_flags flags)
1134 {
1135         struct bch_fs *c = trans->c;
1136         struct btree_iter iter, update_iter;
1137         struct bpos start = bkey_start_pos(&insert->k);
1138         struct bkey_i *update;
1139         struct bkey_s_c k;
1140         enum btree_id btree_id = orig_iter->btree_id;
1141         int ret = 0, compressed_sectors;
1142
1143         bch2_trans_iter_init(trans, &iter, btree_id, start,
1144                              BTREE_ITER_INTENT|
1145                              BTREE_ITER_WITH_UPDATES|
1146                              BTREE_ITER_NOT_EXTENTS);
1147         k = bch2_btree_iter_peek(&iter);
1148         if ((ret = bkey_err(k)))
1149                 goto err;
1150         if (!k.k)
1151                 goto out;
1152
1153         if (bch2_bkey_maybe_mergable(k.k, &insert->k)) {
1154                 /*
1155                  * We can't merge extents if they belong to interior snapshot
1156                  * tree nodes, and there's a snapshot in which one extent is
1157                  * visible and the other is not - i.e. if visibility is
1158                  * different.
1159                  *
1160                  * Instead of checking if visibilitiy of the two extents is
1161                  * different, for now we just check if either has been
1162                  * overwritten:
1163                  */
1164                 ret = check_pos_snapshot_overwritten(trans, btree_id, insert->k.p);
1165                 if (ret < 0)
1166                         goto err;
1167                 if (ret)
1168                         goto nomerge1;
1169
1170                 ret = check_pos_snapshot_overwritten(trans, btree_id, k.k->p);
1171                 if (ret < 0)
1172                         goto err;
1173                 if (ret)
1174                         goto nomerge1;
1175
1176                 update = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
1177                 if ((ret = PTR_ERR_OR_ZERO(update)))
1178                         goto err;
1179
1180                 bkey_reassemble(update, k);
1181
1182                 if (bch2_bkey_merge(c, bkey_i_to_s(update), bkey_i_to_s_c(insert))) {
1183                         ret = bch2_btree_delete_at(trans, &iter, flags);
1184                         if (ret)
1185                                 goto err;
1186
1187                         insert = update;
1188                         goto next;
1189                 }
1190         }
1191 nomerge1:
1192         ret = 0;
1193         if (!bkey_cmp(k.k->p, start))
1194                 goto next;
1195
1196         while (bkey_cmp(insert->k.p, bkey_start_pos(k.k)) > 0) {
1197                 bool front_split = bkey_cmp(bkey_start_pos(k.k), start) < 0;
1198                 bool back_split  = bkey_cmp(k.k->p, insert->k.p) > 0;
1199
1200                 /*
1201                  * If we're going to be splitting a compressed extent, note it
1202                  * so that __bch2_trans_commit() can increase our disk
1203                  * reservation:
1204                  */
1205                 if (((front_split && back_split) ||
1206                      ((front_split || back_split) && k.k->p.snapshot != insert->k.p.snapshot)) &&
1207                     (compressed_sectors = bch2_bkey_sectors_compressed(k)))
1208                         trans->extra_journal_res += compressed_sectors;
1209
1210                 if (front_split) {
1211                         update = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
1212                         if ((ret = PTR_ERR_OR_ZERO(update)))
1213                                 goto err;
1214
1215                         bkey_reassemble(update, k);
1216
1217                         bch2_cut_back(start, update);
1218
1219                         bch2_trans_iter_init(trans, &update_iter, btree_id, update->k.p,
1220                                              BTREE_ITER_NOT_EXTENTS|
1221                                              BTREE_ITER_ALL_SNAPSHOTS|
1222                                              BTREE_ITER_INTENT);
1223                         ret   = bch2_btree_iter_traverse(&update_iter) ?:
1224                                 bch2_trans_update(trans, &update_iter, update,
1225                                                   BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE|
1226                                                   flags);
1227                         bch2_trans_iter_exit(trans, &update_iter);
1228
1229                         if (ret)
1230                                 goto err;
1231                 }
1232
1233                 if (k.k->p.snapshot != insert->k.p.snapshot &&
1234                     (front_split || back_split)) {
1235                         update = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
1236                         if ((ret = PTR_ERR_OR_ZERO(update)))
1237                                 goto err;
1238
1239                         bkey_reassemble(update, k);
1240
1241                         bch2_cut_front(start, update);
1242                         bch2_cut_back(insert->k.p, update);
1243
1244                         bch2_trans_iter_init(trans, &update_iter, btree_id, update->k.p,
1245                                              BTREE_ITER_NOT_EXTENTS|
1246                                              BTREE_ITER_ALL_SNAPSHOTS|
1247                                              BTREE_ITER_INTENT);
1248                         ret   = bch2_btree_iter_traverse(&update_iter) ?:
1249                                 bch2_trans_update(trans, &update_iter, update,
1250                                                   BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE|
1251                                                   flags);
1252                         bch2_trans_iter_exit(trans, &update_iter);
1253                         if (ret)
1254                                 goto err;
1255                 }
1256
1257                 if (bkey_cmp(k.k->p, insert->k.p) <= 0) {
1258                         update = bch2_trans_kmalloc(trans, sizeof(*update));
1259                         if ((ret = PTR_ERR_OR_ZERO(update)))
1260                                 goto err;
1261
1262                         bkey_init(&update->k);
1263                         update->k.p = k.k->p;
1264
1265                         if (insert->k.p.snapshot != k.k->p.snapshot) {
1266                                 update->k.p.snapshot = insert->k.p.snapshot;
1267                                 update->k.type = KEY_TYPE_whiteout;
1268                         }
1269
1270                         bch2_trans_iter_init(trans, &update_iter, btree_id, update->k.p,
1271                                              BTREE_ITER_NOT_EXTENTS|
1272                                              BTREE_ITER_INTENT);
1273                         ret   = bch2_btree_iter_traverse(&update_iter) ?:
1274                                 bch2_trans_update(trans, &update_iter, update,
1275                                                   BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE|
1276                                                   flags);
1277                         bch2_trans_iter_exit(trans, &update_iter);
1278
1279                         if (ret)
1280                                 goto err;
1281                 }
1282
1283                 if (back_split) {
1284                         update = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
1285                         if ((ret = PTR_ERR_OR_ZERO(update)))
1286                                 goto err;
1287
1288                         bkey_reassemble(update, k);
1289                         bch2_cut_front(insert->k.p, update);
1290
1291                         ret = bch2_trans_update_by_path(trans, iter.path, update,
1292                                                   BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE|
1293                                                   flags);
1294                         if (ret)
1295                                 goto err;
1296                         goto out;
1297                 }
1298 next:
1299                 k = bch2_btree_iter_next(&iter);
1300                 if ((ret = bkey_err(k)))
1301                         goto err;
1302                 if (!k.k)
1303                         goto out;
1304         }
1305
1306         if (bch2_bkey_maybe_mergable(&insert->k, k.k)) {
1307                 ret = check_pos_snapshot_overwritten(trans, btree_id, insert->k.p);
1308                 if (ret < 0)
1309                         goto err;
1310                 if (ret)
1311                         goto nomerge2;
1312
1313                 ret = check_pos_snapshot_overwritten(trans, btree_id, k.k->p);
1314                 if (ret < 0)
1315                         goto err;
1316                 if (ret)
1317                         goto nomerge2;
1318
1319                 bch2_bkey_merge(c, bkey_i_to_s(insert), k);
1320         }
1321 nomerge2:
1322         ret = 0;
1323 out:
1324         if (!bkey_deleted(&insert->k)) {
1325                 /*
1326                  * Rewinding iterators is expensive: get a new one and the one
1327                  * that points to the start of insert will be cloned from:
1328                  */
1329                 bch2_trans_iter_exit(trans, &iter);
1330                 bch2_trans_iter_init(trans, &iter, btree_id, insert->k.p,
1331                                      BTREE_ITER_NOT_EXTENTS|
1332                                      BTREE_ITER_INTENT);
1333                 ret   = bch2_btree_iter_traverse(&iter) ?:
1334                         bch2_trans_update(trans, &iter, insert, flags);
1335         }
1336 err:
1337         bch2_trans_iter_exit(trans, &iter);
1338
1339         return ret;
1340 }
1341
1342 /*
1343  * When deleting, check if we need to emit a whiteout (because we're overwriting
1344  * something in an ancestor snapshot)
1345  */
1346 static int need_whiteout_for_snapshot(struct btree_trans *trans,
1347                                       enum btree_id btree_id, struct bpos pos)
1348 {
1349         struct btree_iter iter;
1350         struct bkey_s_c k;
1351         u32 snapshot = pos.snapshot;
1352         int ret;
1353
1354         if (!bch2_snapshot_parent(trans->c, pos.snapshot))
1355                 return 0;
1356
1357         pos.snapshot++;
1358
1359         for_each_btree_key_norestart(trans, iter, btree_id, pos,
1360                            BTREE_ITER_ALL_SNAPSHOTS|
1361                            BTREE_ITER_NOPRESERVE, k, ret) {
1362                 if (bkey_cmp(k.k->p, pos))
1363                         break;
1364
1365                 if (bch2_snapshot_is_ancestor(trans->c, snapshot,
1366                                               k.k->p.snapshot)) {
1367                         ret = !bkey_whiteout(k.k);
1368                         break;
1369                 }
1370         }
1371         bch2_trans_iter_exit(trans, &iter);
1372
1373         return ret;
1374 }
1375
1376 static int __must_check
1377 bch2_trans_update_by_path(struct btree_trans *trans, struct btree_path *path,
1378                           struct bkey_i *k, enum btree_update_flags flags)
1379 {
1380         struct btree_insert_entry *i, n;
1381
1382         BUG_ON(!path->should_be_locked);
1383
1384         BUG_ON(trans->nr_updates >= BTREE_ITER_MAX);
1385         BUG_ON(bpos_cmp(k->k.p, path->pos));
1386
1387         n = (struct btree_insert_entry) {
1388                 .flags          = flags,
1389                 .bkey_type      = __btree_node_type(path->level, path->btree_id),
1390                 .btree_id       = path->btree_id,
1391                 .level          = path->level,
1392                 .cached         = path->cached,
1393                 .path           = path,
1394                 .k              = k,
1395                 .ip_allocated   = _RET_IP_,
1396         };
1397
1398 #ifdef CONFIG_BCACHEFS_DEBUG
1399         trans_for_each_update(trans, i)
1400                 BUG_ON(i != trans->updates &&
1401                        btree_insert_entry_cmp(i - 1, i) >= 0);
1402 #endif
1403
1404         /*
1405          * Pending updates are kept sorted: first, find position of new update,
1406          * then delete/trim any updates the new update overwrites:
1407          */
1408         trans_for_each_update(trans, i)
1409                 if (btree_insert_entry_cmp(&n, i) <= 0)
1410                         break;
1411
1412         if (i < trans->updates + trans->nr_updates &&
1413             !btree_insert_entry_cmp(&n, i)) {
1414                 BUG_ON(i->insert_trigger_run || i->overwrite_trigger_run);
1415
1416                 bch2_path_put(trans, i->path, true);
1417                 *i = n;
1418         } else
1419                 array_insert_item(trans->updates, trans->nr_updates,
1420                                   i - trans->updates, n);
1421
1422         __btree_path_get(n.path, true);
1423         return 0;
1424 }
1425
1426 int __must_check bch2_trans_update(struct btree_trans *trans, struct btree_iter *iter,
1427                                    struct bkey_i *k, enum btree_update_flags flags)
1428 {
1429         struct btree_path *path = iter->update_path ?: iter->path;
1430         struct bkey_cached *ck;
1431         int ret;
1432
1433         if (iter->flags & BTREE_ITER_IS_EXTENTS)
1434                 return bch2_trans_update_extent(trans, iter, k, flags);
1435
1436         if (bkey_deleted(&k->k) &&
1437             !(flags & BTREE_UPDATE_KEY_CACHE_RECLAIM) &&
1438             (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)) {
1439                 ret = need_whiteout_for_snapshot(trans, iter->btree_id, k->k.p);
1440                 if (unlikely(ret < 0))
1441                         return ret;
1442
1443                 if (ret)
1444                         k->k.type = KEY_TYPE_whiteout;
1445         }
1446
1447         if (!(flags & BTREE_UPDATE_KEY_CACHE_RECLAIM) &&
1448             !path->cached &&
1449             !path->level &&
1450             btree_id_cached(trans->c, path->btree_id)) {
1451                 if (!iter->key_cache_path ||
1452                     !iter->key_cache_path->should_be_locked ||
1453                     bpos_cmp(iter->key_cache_path->pos, k->k.p)) {
1454                         if (!iter->key_cache_path)
1455                                 iter->key_cache_path =
1456                                         bch2_path_get(trans, path->btree_id, path->pos, 1, 0,
1457                                                       BTREE_ITER_INTENT|
1458                                                       BTREE_ITER_CACHED, _THIS_IP_);
1459
1460                         iter->key_cache_path =
1461                                 bch2_btree_path_set_pos(trans, iter->key_cache_path, path->pos,
1462                                                         iter->flags & BTREE_ITER_INTENT,
1463                                                         _THIS_IP_);
1464
1465                         ret = bch2_btree_path_traverse(trans, iter->key_cache_path,
1466                                                        BTREE_ITER_CACHED|
1467                                                        BTREE_ITER_CACHED_NOFILL);
1468                         if (unlikely(ret))
1469                                 return ret;
1470
1471                         ck = (void *) iter->key_cache_path->l[0].b;
1472
1473                         if (test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
1474                                 trace_trans_restart_key_cache_raced(trans->fn, _RET_IP_);
1475                                 btree_trans_restart(trans);
1476                                 return -EINTR;
1477                         }
1478
1479                         iter->key_cache_path->should_be_locked = true;
1480                 }
1481
1482                 path = iter->key_cache_path;
1483         }
1484
1485         return bch2_trans_update_by_path(trans, path, k, flags);
1486 }
1487
1488 void bch2_trans_commit_hook(struct btree_trans *trans,
1489                             struct btree_trans_commit_hook *h)
1490 {
1491         h->next = trans->hooks;
1492         trans->hooks = h;
1493 }
1494
1495 int __bch2_btree_insert(struct btree_trans *trans,
1496                         enum btree_id id, struct bkey_i *k)
1497 {
1498         struct btree_iter iter;
1499         int ret;
1500
1501         bch2_trans_iter_init(trans, &iter, id, bkey_start_pos(&k->k),
1502                              BTREE_ITER_INTENT);
1503         ret   = bch2_btree_iter_traverse(&iter) ?:
1504                 bch2_trans_update(trans, &iter, k, 0);
1505         bch2_trans_iter_exit(trans, &iter);
1506         return ret;
1507 }
1508
1509 /**
1510  * bch2_btree_insert - insert keys into the extent btree
1511  * @c:                  pointer to struct bch_fs
1512  * @id:                 btree to insert into
1513  * @insert_keys:        list of keys to insert
1514  * @hook:               insert callback
1515  */
1516 int bch2_btree_insert(struct bch_fs *c, enum btree_id id,
1517                       struct bkey_i *k,
1518                       struct disk_reservation *disk_res,
1519                       u64 *journal_seq, int flags)
1520 {
1521         return bch2_trans_do(c, disk_res, journal_seq, flags,
1522                              __bch2_btree_insert(&trans, id, k));
1523 }
1524
1525 int bch2_btree_delete_at(struct btree_trans *trans,
1526                          struct btree_iter *iter, unsigned update_flags)
1527 {
1528         struct bkey_i *k;
1529
1530         k = bch2_trans_kmalloc(trans, sizeof(*k));
1531         if (IS_ERR(k))
1532                 return PTR_ERR(k);
1533
1534         bkey_init(&k->k);
1535         k->k.p = iter->pos;
1536         return bch2_trans_update(trans, iter, k, update_flags);
1537 }
1538
1539 int bch2_btree_delete_range_trans(struct btree_trans *trans, enum btree_id id,
1540                                   struct bpos start, struct bpos end,
1541                                   unsigned iter_flags,
1542                                   u64 *journal_seq)
1543 {
1544         struct btree_iter iter;
1545         struct bkey_s_c k;
1546         int ret = 0;
1547
1548         bch2_trans_iter_init(trans, &iter, id, start, BTREE_ITER_INTENT|iter_flags);
1549 retry:
1550         while ((bch2_trans_begin(trans),
1551                (k = bch2_btree_iter_peek(&iter)).k) &&
1552                !(ret = bkey_err(k)) &&
1553                bkey_cmp(iter.pos, end) < 0) {
1554                 struct disk_reservation disk_res =
1555                         bch2_disk_reservation_init(trans->c, 0);
1556                 struct bkey_i delete;
1557
1558                 bkey_init(&delete.k);
1559
1560                 /*
1561                  * This could probably be more efficient for extents:
1562                  */
1563
1564                 /*
1565                  * For extents, iter.pos won't necessarily be the same as
1566                  * bkey_start_pos(k.k) (for non extents they always will be the
1567                  * same). It's important that we delete starting from iter.pos
1568                  * because the range we want to delete could start in the middle
1569                  * of k.
1570                  *
1571                  * (bch2_btree_iter_peek() does guarantee that iter.pos >=
1572                  * bkey_start_pos(k.k)).
1573                  */
1574                 delete.k.p = iter.pos;
1575
1576                 if (iter.flags & BTREE_ITER_IS_EXTENTS) {
1577                         unsigned max_sectors =
1578                                 KEY_SIZE_MAX & (~0 << trans->c->block_bits);
1579
1580                         /* create the biggest key we can */
1581                         bch2_key_resize(&delete.k, max_sectors);
1582                         bch2_cut_back(end, &delete);
1583
1584                         ret = bch2_extent_trim_atomic(trans, &iter, &delete);
1585                         if (ret)
1586                                 break;
1587                 }
1588
1589                 ret   = bch2_trans_update(trans, &iter, &delete, 0) ?:
1590                         bch2_trans_commit(trans, &disk_res, journal_seq,
1591                                         BTREE_INSERT_NOFAIL);
1592                 bch2_disk_reservation_put(trans->c, &disk_res);
1593                 if (ret)
1594                         break;
1595         }
1596
1597         if (ret == -EINTR) {
1598                 ret = 0;
1599                 goto retry;
1600         }
1601
1602         bch2_trans_iter_exit(trans, &iter);
1603         return ret;
1604 }
1605
1606 /*
1607  * bch_btree_delete_range - delete everything within a given range
1608  *
1609  * Range is a half open interval - [start, end)
1610  */
1611 int bch2_btree_delete_range(struct bch_fs *c, enum btree_id id,
1612                             struct bpos start, struct bpos end,
1613                             unsigned iter_flags,
1614                             u64 *journal_seq)
1615 {
1616         return bch2_trans_do(c, NULL, journal_seq, 0,
1617                              bch2_btree_delete_range_trans(&trans, id, start, end,
1618                                                            iter_flags, journal_seq));
1619 }