xref: /linux/fs/bcachefs/btree_trans_commit.c (revision fcab107abe1ab5be9dbe874baa722372da8f4f73)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include "bcachefs.h"
4 #include "alloc_foreground.h"
5 #include "btree_gc.h"
6 #include "btree_io.h"
7 #include "btree_iter.h"
8 #include "btree_journal_iter.h"
9 #include "btree_key_cache.h"
10 #include "btree_update_interior.h"
11 #include "btree_write_buffer.h"
12 #include "buckets.h"
13 #include "disk_accounting.h"
14 #include "enumerated_ref.h"
15 #include "errcode.h"
16 #include "error.h"
17 #include "journal.h"
18 #include "journal_io.h"
19 #include "journal_reclaim.h"
20 #include "replicas.h"
21 #include "snapshot.h"
22 
23 #include <linux/prefetch.h>
24 #include <linux/string_helpers.h>
25 
26 static const char * const trans_commit_flags_strs[] = {
27 #define x(n, ...) #n,
28 	BCH_TRANS_COMMIT_FLAGS()
29 #undef x
30 	NULL
31 };
32 
33 void bch2_trans_commit_flags_to_text(struct printbuf *out, enum bch_trans_commit_flags flags)
34 {
35 	enum bch_watermark watermark = flags & BCH_WATERMARK_MASK;
36 
37 	prt_printf(out, "watermark=%s", bch2_watermarks[watermark]);
38 
39 	flags >>= BCH_WATERMARK_BITS;
40 	if (flags) {
41 		prt_char(out, ' ');
42 		bch2_prt_bitflags(out, trans_commit_flags_strs, flags);
43 	}
44 }
45 
46 static void verify_update_old_key(struct btree_trans *trans, struct btree_insert_entry *i)
47 {
48 #ifdef CONFIG_BCACHEFS_DEBUG
49 	struct bch_fs *c = trans->c;
50 	struct bkey u;
51 	struct bkey_s_c k = bch2_btree_path_peek_slot_exact(trans->paths + i->path, &u);
52 
53 	if (unlikely(trans->journal_replay_not_finished)) {
54 		struct bkey_i *j_k =
55 			bch2_journal_keys_peek_slot(c, i->btree_id, i->level, i->k->k.p);
56 
57 		if (j_k)
58 			k = bkey_i_to_s_c(j_k);
59 	}
60 
61 	u = *k.k;
62 	u.needs_whiteout = i->old_k.needs_whiteout;
63 
64 	BUG_ON(memcmp(&i->old_k, &u, sizeof(struct bkey)));
65 	BUG_ON(i->old_v != k.v);
66 #endif
67 }
68 
69 static inline struct btree_path_level *insert_l(struct btree_trans *trans, struct btree_insert_entry *i)
70 {
71 	return (trans->paths + i->path)->l + i->level;
72 }
73 
74 static inline bool same_leaf_as_prev(struct btree_trans *trans,
75 				     struct btree_insert_entry *i)
76 {
77 	return i != trans->updates &&
78 		insert_l(trans, &i[0])->b == insert_l(trans, &i[-1])->b;
79 }
80 
81 static inline bool same_leaf_as_next(struct btree_trans *trans,
82 				     struct btree_insert_entry *i)
83 {
84 	return i + 1 < trans->updates + trans->nr_updates &&
85 		insert_l(trans, &i[0])->b == insert_l(trans, &i[1])->b;
86 }
87 
88 inline void bch2_btree_node_prep_for_write(struct btree_trans *trans,
89 					   struct btree_path *path,
90 					   struct btree *b)
91 {
92 	struct bch_fs *c = trans->c;
93 
94 	if (unlikely(btree_node_just_written(b)) &&
95 	    bch2_btree_post_write_cleanup(c, b))
96 		bch2_trans_node_reinit_iter(trans, b);
97 
98 	/*
99 	 * If the last bset has been written, or if it's gotten too big - start
100 	 * a new bset to insert into:
101 	 */
102 	if (want_new_bset(c, b))
103 		bch2_btree_init_next(trans, b);
104 }
105 
106 static noinline int trans_lock_write_fail(struct btree_trans *trans, struct btree_insert_entry *i)
107 {
108 	while (--i >= trans->updates) {
109 		if (same_leaf_as_prev(trans, i))
110 			continue;
111 
112 		bch2_btree_node_unlock_write(trans, trans->paths + i->path, insert_l(trans, i)->b);
113 	}
114 
115 	trace_and_count(trans->c, trans_restart_would_deadlock_write, trans);
116 	return btree_trans_restart(trans, BCH_ERR_transaction_restart_would_deadlock_write);
117 }
118 
119 static inline int bch2_trans_lock_write(struct btree_trans *trans)
120 {
121 	EBUG_ON(trans->write_locked);
122 
123 	trans_for_each_update(trans, i) {
124 		if (same_leaf_as_prev(trans, i))
125 			continue;
126 
127 		if (bch2_btree_node_lock_write(trans, trans->paths + i->path, &insert_l(trans, i)->b->c))
128 			return trans_lock_write_fail(trans, i);
129 
130 		if (!i->cached)
131 			bch2_btree_node_prep_for_write(trans, trans->paths + i->path, insert_l(trans, i)->b);
132 	}
133 
134 	trans->write_locked = true;
135 	return 0;
136 }
137 
138 static inline void bch2_trans_unlock_updates_write(struct btree_trans *trans)
139 {
140 	if (likely(trans->write_locked)) {
141 		trans_for_each_update(trans, i)
142 			if (btree_node_locked_type(trans->paths + i->path, i->level) ==
143 			    BTREE_NODE_WRITE_LOCKED)
144 				bch2_btree_node_unlock_write_inlined(trans,
145 						trans->paths + i->path, insert_l(trans, i)->b);
146 		trans->write_locked = false;
147 	}
148 }
149 
150 /* Inserting into a given leaf node (last stage of insert): */
151 
152 /* Handle overwrites and do insert, for non extents: */
153 bool bch2_btree_bset_insert_key(struct btree_trans *trans,
154 				struct btree_path *path,
155 				struct btree *b,
156 				struct btree_node_iter *node_iter,
157 				struct bkey_i *insert)
158 {
159 	struct bkey_packed *k;
160 	unsigned clobber_u64s = 0, new_u64s = 0;
161 
162 	EBUG_ON(btree_node_just_written(b));
163 	EBUG_ON(bset_written(b, btree_bset_last(b)));
164 	EBUG_ON(bkey_deleted(&insert->k) && bkey_val_u64s(&insert->k));
165 	EBUG_ON(bpos_lt(insert->k.p, b->data->min_key));
166 	EBUG_ON(bpos_gt(insert->k.p, b->data->max_key));
167 	EBUG_ON(insert->k.u64s > bch2_btree_keys_u64s_remaining(b));
168 	EBUG_ON(!b->c.level && !bpos_eq(insert->k.p, path->pos));
169 	kmsan_check_memory(insert, bkey_bytes(&insert->k));
170 
171 	k = bch2_btree_node_iter_peek_all(node_iter, b);
172 	if (k && bkey_cmp_left_packed(b, k, &insert->k.p))
173 		k = NULL;
174 
175 	/* @k is the key being overwritten/deleted, if any: */
176 	EBUG_ON(k && bkey_deleted(k));
177 
178 	/* Deleting, but not found? nothing to do: */
179 	if (bkey_deleted(&insert->k) && !k)
180 		return false;
181 
182 	if (bkey_deleted(&insert->k)) {
183 		/* Deleting: */
184 		btree_account_key_drop(b, k);
185 		k->type = KEY_TYPE_deleted;
186 
187 		if (k->needs_whiteout)
188 			push_whiteout(b, insert->k.p);
189 		k->needs_whiteout = false;
190 
191 		if (k >= btree_bset_last(b)->start) {
192 			clobber_u64s = k->u64s;
193 			bch2_bset_delete(b, k, clobber_u64s);
194 			goto fix_iter;
195 		} else {
196 			bch2_btree_path_fix_key_modified(trans, b, k);
197 		}
198 
199 		return true;
200 	}
201 
202 	if (k) {
203 		/* Overwriting: */
204 		btree_account_key_drop(b, k);
205 		k->type = KEY_TYPE_deleted;
206 
207 		insert->k.needs_whiteout = k->needs_whiteout;
208 		k->needs_whiteout = false;
209 
210 		if (k >= btree_bset_last(b)->start) {
211 			clobber_u64s = k->u64s;
212 			goto overwrite;
213 		} else {
214 			bch2_btree_path_fix_key_modified(trans, b, k);
215 		}
216 	}
217 
218 	k = bch2_btree_node_iter_bset_pos(node_iter, b, bset_tree_last(b));
219 overwrite:
220 	bch2_bset_insert(b, k, insert, clobber_u64s);
221 	new_u64s = k->u64s;
222 fix_iter:
223 	if (clobber_u64s != new_u64s)
224 		bch2_btree_node_iter_fix(trans, path, b, node_iter, k,
225 					 clobber_u64s, new_u64s);
226 	return true;
227 }
228 
229 static int __btree_node_flush(struct journal *j, struct journal_entry_pin *pin,
230 			       unsigned i, u64 seq)
231 {
232 	struct bch_fs *c = container_of(j, struct bch_fs, journal);
233 	struct btree_write *w = container_of(pin, struct btree_write, journal);
234 	struct btree *b = container_of(w, struct btree, writes[i]);
235 	struct btree_trans *trans = bch2_trans_get(c);
236 	unsigned long old, new;
237 	unsigned idx = w - b->writes;
238 
239 	btree_node_lock_nopath_nofail(trans, &b->c, SIX_LOCK_read);
240 
241 	old = READ_ONCE(b->flags);
242 	do {
243 		new = old;
244 
245 		if (!(old & (1 << BTREE_NODE_dirty)) ||
246 		    !!(old & (1 << BTREE_NODE_write_idx)) != idx ||
247 		    w->journal.seq != seq)
248 			break;
249 
250 		new &= ~BTREE_WRITE_TYPE_MASK;
251 		new |= BTREE_WRITE_journal_reclaim;
252 		new |= 1 << BTREE_NODE_need_write;
253 	} while (!try_cmpxchg(&b->flags, &old, new));
254 
255 	btree_node_write_if_need(trans, b, SIX_LOCK_read);
256 	six_unlock_read(&b->c.lock);
257 
258 	bch2_trans_put(trans);
259 	return 0;
260 }
261 
262 int bch2_btree_node_flush0(struct journal *j, struct journal_entry_pin *pin, u64 seq)
263 {
264 	return __btree_node_flush(j, pin, 0, seq);
265 }
266 
267 int bch2_btree_node_flush1(struct journal *j, struct journal_entry_pin *pin, u64 seq)
268 {
269 	return __btree_node_flush(j, pin, 1, seq);
270 }
271 
272 inline void bch2_btree_add_journal_pin(struct bch_fs *c,
273 				       struct btree *b, u64 seq)
274 {
275 	struct btree_write *w = btree_current_write(b);
276 
277 	bch2_journal_pin_add(&c->journal, seq, &w->journal,
278 			     btree_node_write_idx(b) == 0
279 			     ? bch2_btree_node_flush0
280 			     : bch2_btree_node_flush1);
281 }
282 
283 /**
284  * bch2_btree_insert_key_leaf() - insert a key one key into a leaf node
285  * @trans:		btree transaction object
286  * @path:		path pointing to @insert's pos
287  * @insert:		key to insert
288  * @journal_seq:	sequence number of journal reservation
289  */
290 inline void bch2_btree_insert_key_leaf(struct btree_trans *trans,
291 				       struct btree_path *path,
292 				       struct bkey_i *insert,
293 				       u64 journal_seq)
294 {
295 	struct bch_fs *c = trans->c;
296 	struct btree *b = path_l(path)->b;
297 	struct bset_tree *t = bset_tree_last(b);
298 	struct bset *i = bset(b, t);
299 	int old_u64s = bset_u64s(t);
300 	int old_live_u64s = b->nr.live_u64s;
301 	int live_u64s_added, u64s_added;
302 
303 	if (unlikely(!bch2_btree_bset_insert_key(trans, path, b,
304 					&path_l(path)->iter, insert)))
305 		return;
306 
307 	i->journal_seq = cpu_to_le64(max(journal_seq, le64_to_cpu(i->journal_seq)));
308 
309 	bch2_btree_add_journal_pin(c, b, journal_seq);
310 
311 	if (unlikely(!btree_node_dirty(b))) {
312 		EBUG_ON(test_bit(BCH_FS_clean_shutdown, &c->flags));
313 		set_btree_node_dirty_acct(c, b);
314 	}
315 
316 	live_u64s_added = (int) b->nr.live_u64s - old_live_u64s;
317 	u64s_added = (int) bset_u64s(t) - old_u64s;
318 
319 	if (b->sib_u64s[0] != U16_MAX && live_u64s_added < 0)
320 		b->sib_u64s[0] = max(0, (int) b->sib_u64s[0] + live_u64s_added);
321 	if (b->sib_u64s[1] != U16_MAX && live_u64s_added < 0)
322 		b->sib_u64s[1] = max(0, (int) b->sib_u64s[1] + live_u64s_added);
323 
324 	if (u64s_added > live_u64s_added &&
325 	    bch2_maybe_compact_whiteouts(c, b))
326 		bch2_trans_node_reinit_iter(trans, b);
327 }
328 
329 /* Cached btree updates: */
330 
331 /* Normal update interface: */
332 
333 static inline void btree_insert_entry_checks(struct btree_trans *trans,
334 					     struct btree_insert_entry *i)
335 {
336 	struct btree_path *path = trans->paths + i->path;
337 
338 	BUG_ON(!bpos_eq(i->k->k.p, path->pos));
339 	BUG_ON(i->cached	!= path->cached);
340 	BUG_ON(i->level		!= path->level);
341 	BUG_ON(i->btree_id	!= path->btree_id);
342 	BUG_ON(i->bkey_type	!= __btree_node_type(path->level, path->btree_id));
343 	EBUG_ON(!i->level &&
344 		btree_type_has_snapshots(i->btree_id) &&
345 		!(i->flags & BTREE_UPDATE_internal_snapshot_node) &&
346 		test_bit(JOURNAL_replay_done, &trans->c->journal.flags) &&
347 		i->k->k.p.snapshot &&
348 		bch2_snapshot_is_internal_node(trans->c, i->k->k.p.snapshot) > 0);
349 }
350 
351 static __always_inline int bch2_trans_journal_res_get(struct btree_trans *trans,
352 						      unsigned flags)
353 {
354 	return bch2_journal_res_get(&trans->c->journal, &trans->journal_res,
355 				    trans->journal_u64s, flags, trans);
356 }
357 
358 #define JSET_ENTRY_LOG_U64s		4
359 
360 static noinline void journal_transaction_name(struct btree_trans *trans)
361 {
362 	struct bch_fs *c = trans->c;
363 	struct journal *j = &c->journal;
364 	struct jset_entry *entry =
365 		bch2_journal_add_entry(j, &trans->journal_res,
366 				       BCH_JSET_ENTRY_log, 0, 0,
367 				       JSET_ENTRY_LOG_U64s);
368 	struct jset_entry_log *l =
369 		container_of(entry, struct jset_entry_log, entry);
370 
371 	memcpy_and_pad(l->d, JSET_ENTRY_LOG_U64s * sizeof(u64),
372 		       trans->fn, strlen(trans->fn), 0);
373 }
374 
375 static inline int btree_key_can_insert(struct btree_trans *trans,
376 				       struct btree *b, unsigned u64s)
377 {
378 	if (!bch2_btree_node_insert_fits(b, u64s))
379 		return bch_err_throw(trans->c, btree_insert_btree_node_full);
380 
381 	return 0;
382 }
383 
384 noinline static int
385 btree_key_can_insert_cached_slowpath(struct btree_trans *trans, unsigned flags,
386 				     struct btree_path *path, unsigned new_u64s)
387 {
388 	struct bkey_cached *ck = (void *) path->l[0].b;
389 	struct bkey_i *new_k;
390 	int ret;
391 
392 	bch2_trans_unlock_updates_write(trans);
393 	bch2_trans_unlock(trans);
394 
395 	new_k = kmalloc(new_u64s * sizeof(u64), GFP_KERNEL);
396 	if (!new_k) {
397 		struct bch_fs *c = trans->c;
398 		bch_err(c, "error allocating memory for key cache key, btree %s u64s %u",
399 			bch2_btree_id_str(path->btree_id), new_u64s);
400 		return bch_err_throw(c, ENOMEM_btree_key_cache_insert);
401 	}
402 
403 	ret =   bch2_trans_relock(trans) ?:
404 		bch2_trans_lock_write(trans);
405 	if (unlikely(ret)) {
406 		kfree(new_k);
407 		return ret;
408 	}
409 
410 	memcpy(new_k, ck->k, ck->u64s * sizeof(u64));
411 
412 	trans_for_each_update(trans, i)
413 		if (i->old_v == &ck->k->v)
414 			i->old_v = &new_k->v;
415 
416 	kfree(ck->k);
417 	ck->u64s	= new_u64s;
418 	ck->k		= new_k;
419 	return 0;
420 }
421 
422 static int btree_key_can_insert_cached(struct btree_trans *trans, unsigned flags,
423 				       struct btree_path *path, unsigned u64s)
424 {
425 	struct bch_fs *c = trans->c;
426 	struct bkey_cached *ck = (void *) path->l[0].b;
427 	unsigned new_u64s;
428 	struct bkey_i *new_k;
429 	unsigned watermark = flags & BCH_WATERMARK_MASK;
430 
431 	EBUG_ON(path->level);
432 
433 	if (watermark < BCH_WATERMARK_reclaim &&
434 	    !test_bit(BKEY_CACHED_DIRTY, &ck->flags) &&
435 	    bch2_btree_key_cache_must_wait(c))
436 		return bch_err_throw(c, btree_insert_need_journal_reclaim);
437 
438 	/*
439 	 * bch2_varint_decode can read past the end of the buffer by at most 7
440 	 * bytes (it won't be used):
441 	 */
442 	u64s += 1;
443 
444 	if (u64s <= ck->u64s)
445 		return 0;
446 
447 	new_u64s	= roundup_pow_of_two(u64s);
448 	new_k		= krealloc(ck->k, new_u64s * sizeof(u64), GFP_NOWAIT|__GFP_NOWARN);
449 	if (unlikely(!new_k))
450 		return btree_key_can_insert_cached_slowpath(trans, flags, path, new_u64s);
451 
452 	trans_for_each_update(trans, i)
453 		if (i->old_v == &ck->k->v)
454 			i->old_v = &new_k->v;
455 
456 	ck->u64s	= new_u64s;
457 	ck->k		= new_k;
458 	return 0;
459 }
460 
461 /* Triggers: */
462 
463 static int run_one_mem_trigger(struct btree_trans *trans,
464 			       struct btree_insert_entry *i,
465 			       unsigned flags)
466 {
467 	verify_update_old_key(trans, i);
468 
469 	if (unlikely(flags & BTREE_TRIGGER_norun))
470 		return 0;
471 
472 	struct bkey_s_c old = { &i->old_k, i->old_v };
473 	struct bkey_i *new = i->k;
474 	const struct bkey_ops *old_ops = bch2_bkey_type_ops(old.k->type);
475 	const struct bkey_ops *new_ops = bch2_bkey_type_ops(i->k->k.type);
476 
477 	if (old_ops->trigger == new_ops->trigger)
478 		return bch2_key_trigger(trans, i->btree_id, i->level,
479 				old, bkey_i_to_s(new),
480 				BTREE_TRIGGER_insert|BTREE_TRIGGER_overwrite|flags);
481 	else
482 		return bch2_key_trigger_new(trans, i->btree_id, i->level,
483 				bkey_i_to_s(new), flags) ?:
484 		       bch2_key_trigger_old(trans, i->btree_id, i->level,
485 				old, flags);
486 }
487 
488 static int run_one_trans_trigger(struct btree_trans *trans, struct btree_insert_entry *i)
489 {
490 	verify_update_old_key(trans, i);
491 
492 	if ((i->flags & BTREE_TRIGGER_norun) ||
493 	    !btree_node_type_has_trans_triggers(i->bkey_type))
494 		return 0;
495 
496 	/*
497 	 * Transactional triggers create new btree_insert_entries, so we can't
498 	 * pass them a pointer to a btree_insert_entry, that memory is going to
499 	 * move:
500 	 */
501 	struct bkey old_k = i->old_k;
502 	struct bkey_s_c old = { &old_k, i->old_v };
503 	const struct bkey_ops *old_ops = bch2_bkey_type_ops(old.k->type);
504 	const struct bkey_ops *new_ops = bch2_bkey_type_ops(i->k->k.type);
505 	unsigned flags = i->flags|BTREE_TRIGGER_transactional;
506 
507 	if (!i->insert_trigger_run &&
508 	    !i->overwrite_trigger_run &&
509 	    old_ops->trigger == new_ops->trigger) {
510 		i->overwrite_trigger_run = true;
511 		i->insert_trigger_run = true;
512 		return bch2_key_trigger(trans, i->btree_id, i->level, old, bkey_i_to_s(i->k),
513 					BTREE_TRIGGER_insert|
514 					BTREE_TRIGGER_overwrite|flags) ?: 1;
515 	} else if (!i->overwrite_trigger_run) {
516 		i->overwrite_trigger_run = true;
517 		return bch2_key_trigger_old(trans, i->btree_id, i->level, old, flags) ?: 1;
518 	} else if (!i->insert_trigger_run) {
519 		i->insert_trigger_run = true;
520 		return bch2_key_trigger_new(trans, i->btree_id, i->level, bkey_i_to_s(i->k), flags) ?: 1;
521 	} else {
522 		return 0;
523 	}
524 }
525 
526 static int bch2_trans_commit_run_triggers(struct btree_trans *trans)
527 {
528 	unsigned sort_id_start = 0;
529 
530 	while (sort_id_start < trans->nr_updates) {
531 		unsigned i, sort_id = trans->updates[sort_id_start].sort_order;
532 		bool trans_trigger_run;
533 
534 		/*
535 		 * For a given btree, this algorithm runs insert triggers before
536 		 * overwrite triggers: this is so that when extents are being
537 		 * moved (e.g. by FALLOCATE_FL_INSERT_RANGE), we don't drop
538 		 * references before they are re-added.
539 		 *
540 		 * Running triggers will append more updates to the list of
541 		 * updates as we're walking it:
542 		 */
543 		do {
544 			trans_trigger_run = false;
545 
546 			for (i = sort_id_start;
547 			     i < trans->nr_updates && trans->updates[i].sort_order <= sort_id;
548 			     i++) {
549 				if (trans->updates[i].sort_order < sort_id) {
550 					sort_id_start = i;
551 					continue;
552 				}
553 
554 				int ret = run_one_trans_trigger(trans, trans->updates + i);
555 				if (ret < 0)
556 					return ret;
557 				if (ret)
558 					trans_trigger_run = true;
559 			}
560 		} while (trans_trigger_run);
561 
562 		sort_id_start = i;
563 	}
564 
565 #ifdef CONFIG_BCACHEFS_DEBUG
566 	trans_for_each_update(trans, i)
567 		BUG_ON(!(i->flags & BTREE_TRIGGER_norun) &&
568 		       btree_node_type_has_trans_triggers(i->bkey_type) &&
569 		       (!i->insert_trigger_run || !i->overwrite_trigger_run));
570 #endif
571 	return 0;
572 }
573 
574 static noinline int bch2_trans_commit_run_gc_triggers(struct btree_trans *trans)
575 {
576 	trans_for_each_update(trans, i)
577 		if (btree_node_type_has_triggers(i->bkey_type) &&
578 		    gc_visited(trans->c, gc_pos_btree(i->btree_id, i->level, i->k->k.p))) {
579 			int ret = run_one_mem_trigger(trans, i, i->flags|BTREE_TRIGGER_gc);
580 			if (ret)
581 				return ret;
582 		}
583 
584 	return 0;
585 }
586 
587 static inline int
588 bch2_trans_commit_write_locked(struct btree_trans *trans, unsigned flags,
589 			       struct btree_insert_entry **stopped_at,
590 			       unsigned long trace_ip)
591 {
592 	struct bch_fs *c = trans->c;
593 	struct btree_trans_commit_hook *h;
594 	unsigned u64s = 0;
595 	int ret = 0;
596 
597 	bch2_trans_verify_not_unlocked_or_in_restart(trans);
598 
599 	if (race_fault()) {
600 		trace_and_count(c, trans_restart_fault_inject, trans, trace_ip);
601 		return btree_trans_restart(trans, BCH_ERR_transaction_restart_fault_inject);
602 	}
603 
604 	/*
605 	 * Check if the insert will fit in the leaf node with the write lock
606 	 * held, otherwise another thread could write the node changing the
607 	 * amount of space available:
608 	 */
609 
610 	prefetch(&trans->c->journal.flags);
611 
612 	trans_for_each_update(trans, i) {
613 		/* Multiple inserts might go to same leaf: */
614 		if (!same_leaf_as_prev(trans, i))
615 			u64s = 0;
616 
617 		u64s += i->k->k.u64s;
618 		ret = !i->cached
619 			? btree_key_can_insert(trans, insert_l(trans, i)->b, u64s)
620 			: btree_key_can_insert_cached(trans, flags, trans->paths + i->path, u64s);
621 		if (ret) {
622 			*stopped_at = i;
623 			return ret;
624 		}
625 
626 		i->k->k.needs_whiteout = false;
627 	}
628 
629 	/*
630 	 * Don't get journal reservation until after we know insert will
631 	 * succeed:
632 	 */
633 	if (likely(!(flags & BCH_TRANS_COMMIT_no_journal_res))) {
634 		ret = bch2_trans_journal_res_get(trans,
635 				(flags & BCH_WATERMARK_MASK)|
636 				JOURNAL_RES_GET_NONBLOCK);
637 		if (ret)
638 			return ret;
639 
640 		if (unlikely(trans->journal_transaction_names))
641 			journal_transaction_name(trans);
642 	}
643 
644 	/*
645 	 * Not allowed to fail after we've gotten our journal reservation - we
646 	 * have to use it:
647 	 */
648 
649 	if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG) &&
650 	    !(flags & BCH_TRANS_COMMIT_no_journal_res)) {
651 		if (static_branch_unlikely(&bch2_journal_seq_verify))
652 			trans_for_each_update(trans, i)
653 				i->k->k.bversion.lo = trans->journal_res.seq;
654 		else if (static_branch_unlikely(&bch2_inject_invalid_keys))
655 			trans_for_each_update(trans, i)
656 				i->k->k.bversion = MAX_VERSION;
657 	}
658 
659 	h = trans->hooks;
660 	while (h) {
661 		ret = h->fn(trans, h);
662 		if (ret)
663 			return ret;
664 		h = h->next;
665 	}
666 
667 	struct bkey_i *accounting;
668 
669 	percpu_down_read(&c->mark_lock);
670 	for (accounting = btree_trans_subbuf_base(trans, &trans->accounting);
671 	     accounting != btree_trans_subbuf_top(trans, &trans->accounting);
672 	     accounting = bkey_next(accounting)) {
673 		ret = bch2_accounting_trans_commit_hook(trans,
674 					bkey_i_to_accounting(accounting), flags);
675 		if (ret)
676 			goto revert_fs_usage;
677 	}
678 	percpu_up_read(&c->mark_lock);
679 
680 	/* XXX: we only want to run this if deltas are nonzero */
681 	bch2_trans_account_disk_usage_change(trans);
682 
683 	trans_for_each_update(trans, i)
684 		if (btree_node_type_has_atomic_triggers(i->bkey_type)) {
685 			ret = run_one_mem_trigger(trans, i, BTREE_TRIGGER_atomic|i->flags);
686 			if (ret)
687 				goto fatal_err;
688 		}
689 
690 	if (unlikely(c->gc_pos.phase)) {
691 		ret = bch2_trans_commit_run_gc_triggers(trans);
692 		if  (ret)
693 			goto fatal_err;
694 	}
695 
696 	struct bkey_validate_context validate_context = { .from	= BKEY_VALIDATE_commit };
697 
698 	if (!(flags & BCH_TRANS_COMMIT_no_journal_res))
699 		validate_context.flags = BCH_VALIDATE_write|BCH_VALIDATE_commit;
700 
701 	for (struct jset_entry *i = btree_trans_journal_entries_start(trans);
702 	     i != btree_trans_journal_entries_top(trans);
703 	     i = vstruct_next(i)) {
704 		ret = bch2_journal_entry_validate(c, NULL, i,
705 						  bcachefs_metadata_version_current,
706 						  CPU_BIG_ENDIAN, validate_context);
707 		if (unlikely(ret)) {
708 			bch2_trans_inconsistent(trans, "invalid journal entry on insert from %s\n",
709 						trans->fn);
710 			goto fatal_err;
711 		}
712 	}
713 
714 	trans_for_each_update(trans, i) {
715 		validate_context.level	= i->level;
716 		validate_context.btree	= i->btree_id;
717 
718 		ret = bch2_bkey_validate(c, bkey_i_to_s_c(i->k), validate_context);
719 		if (unlikely(ret)){
720 			bch2_trans_inconsistent(trans, "invalid bkey on insert from %s -> %ps\n",
721 						trans->fn, (void *) i->ip_allocated);
722 			goto fatal_err;
723 		}
724 		btree_insert_entry_checks(trans, i);
725 	}
726 
727 	if (likely(!(flags & BCH_TRANS_COMMIT_no_journal_res))) {
728 		struct journal *j = &c->journal;
729 		struct jset_entry *entry;
730 
731 		trans_for_each_update(trans, i) {
732 			if (i->key_cache_already_flushed)
733 				continue;
734 
735 			if (i->flags & BTREE_UPDATE_nojournal)
736 				continue;
737 
738 			verify_update_old_key(trans, i);
739 
740 			if (trans->journal_transaction_names) {
741 				entry = bch2_journal_add_entry(j, &trans->journal_res,
742 						       BCH_JSET_ENTRY_overwrite,
743 						       i->btree_id, i->level,
744 						       i->old_k.u64s);
745 				bkey_reassemble((struct bkey_i *) entry->start,
746 						(struct bkey_s_c) { &i->old_k, i->old_v });
747 			}
748 
749 			entry = bch2_journal_add_entry(j, &trans->journal_res,
750 					       BCH_JSET_ENTRY_btree_keys,
751 					       i->btree_id, i->level,
752 					       i->k->k.u64s);
753 			bkey_copy((struct bkey_i *) entry->start, i->k);
754 		}
755 
756 		memcpy_u64s_small(journal_res_entry(&c->journal, &trans->journal_res),
757 				  btree_trans_journal_entries_start(trans),
758 				  trans->journal_entries.u64s);
759 
760 		trans->journal_res.offset	+= trans->journal_entries.u64s;
761 		trans->journal_res.u64s		-= trans->journal_entries.u64s;
762 
763 		memcpy_u64s_small(bch2_journal_add_entry(j, &trans->journal_res,
764 						BCH_JSET_ENTRY_write_buffer_keys,
765 						BTREE_ID_accounting, 0,
766 						trans->accounting.u64s)->_data,
767 				  btree_trans_subbuf_base(trans, &trans->accounting),
768 				  trans->accounting.u64s);
769 
770 		if (trans->journal_seq)
771 			*trans->journal_seq = trans->journal_res.seq;
772 	}
773 
774 	trans_for_each_update(trans, i) {
775 		struct btree_path *path = trans->paths + i->path;
776 
777 		if (!i->cached)
778 			bch2_btree_insert_key_leaf(trans, path, i->k, trans->journal_res.seq);
779 		else if (!i->key_cache_already_flushed)
780 			bch2_btree_insert_key_cached(trans, flags, i);
781 		else
782 			bch2_btree_key_cache_drop(trans, path);
783 	}
784 
785 	return 0;
786 fatal_err:
787 	bch2_fs_fatal_error(c, "fatal error in transaction commit: %s", bch2_err_str(ret));
788 	percpu_down_read(&c->mark_lock);
789 revert_fs_usage:
790 	for (struct bkey_i *i = btree_trans_subbuf_base(trans, &trans->accounting);
791 	     i != accounting;
792 	     i = bkey_next(i))
793 		bch2_accounting_trans_commit_revert(trans, bkey_i_to_accounting(i), flags);
794 	percpu_up_read(&c->mark_lock);
795 	return ret;
796 }
797 
798 static noinline void bch2_drop_overwrites_from_journal(struct btree_trans *trans)
799 {
800 	/*
801 	 * Accounting keys aren't deduped in the journal: we have to compare
802 	 * each individual update against what's in the btree to see if it has
803 	 * been applied yet, and accounting updates also don't overwrite,
804 	 * they're deltas that accumulate.
805 	 */
806 	trans_for_each_update(trans, i)
807 		if (i->k->k.type != KEY_TYPE_accounting)
808 			bch2_journal_key_overwritten(trans->c, i->btree_id, i->level, i->k->k.p);
809 }
810 
811 static int bch2_trans_commit_journal_pin_flush(struct journal *j,
812 				struct journal_entry_pin *_pin, u64 seq)
813 {
814 	return 0;
815 }
816 
817 /*
818  * Get journal reservation, take write locks, and attempt to do btree update(s):
819  */
820 static inline int do_bch2_trans_commit(struct btree_trans *trans, unsigned flags,
821 				       struct btree_insert_entry **stopped_at,
822 				       unsigned long trace_ip)
823 {
824 	struct bch_fs *c = trans->c;
825 	int ret = 0, u64s_delta = 0;
826 
827 	for (unsigned idx = 0; idx < trans->nr_updates; idx++) {
828 		struct btree_insert_entry *i = trans->updates + idx;
829 		if (i->cached)
830 			continue;
831 
832 		u64s_delta += !bkey_deleted(&i->k->k) ? i->k->k.u64s : 0;
833 		u64s_delta -= i->old_btree_u64s;
834 
835 		if (!same_leaf_as_next(trans, i)) {
836 			if (u64s_delta <= 0) {
837 				ret = bch2_foreground_maybe_merge(trans, i->path,
838 							i->level, flags);
839 				if (unlikely(ret))
840 					return ret;
841 			}
842 
843 			u64s_delta = 0;
844 		}
845 	}
846 
847 	ret = bch2_trans_lock_write(trans);
848 	if (unlikely(ret))
849 		return ret;
850 
851 	ret = bch2_trans_commit_write_locked(trans, flags, stopped_at, trace_ip);
852 
853 	if (!ret && unlikely(trans->journal_replay_not_finished))
854 		bch2_drop_overwrites_from_journal(trans);
855 
856 	bch2_trans_unlock_updates_write(trans);
857 
858 	if (!ret && trans->journal_pin)
859 		bch2_journal_pin_add(&c->journal, trans->journal_res.seq,
860 				     trans->journal_pin,
861 				     bch2_trans_commit_journal_pin_flush);
862 
863 	/*
864 	 * Drop journal reservation after dropping write locks, since dropping
865 	 * the journal reservation may kick off a journal write:
866 	 */
867 	if (likely(!(flags & BCH_TRANS_COMMIT_no_journal_res)))
868 		bch2_journal_res_put(&c->journal, &trans->journal_res);
869 
870 	return ret;
871 }
872 
873 static int journal_reclaim_wait_done(struct bch_fs *c)
874 {
875 	int ret = bch2_journal_error(&c->journal) ?:
876 		bch2_btree_key_cache_wait_done(c);
877 
878 	if (!ret)
879 		journal_reclaim_kick(&c->journal);
880 	return ret;
881 }
882 
883 static noinline
884 int bch2_trans_commit_error(struct btree_trans *trans, unsigned flags,
885 			    struct btree_insert_entry *i,
886 			    int ret, unsigned long trace_ip)
887 {
888 	struct bch_fs *c = trans->c;
889 	enum bch_watermark watermark = flags & BCH_WATERMARK_MASK;
890 
891 	if (bch2_err_matches(ret, BCH_ERR_journal_res_blocked)) {
892 		/*
893 		 * XXX: this should probably be a separate BTREE_INSERT_NONBLOCK
894 		 * flag
895 		 */
896 		if ((flags & BCH_TRANS_COMMIT_journal_reclaim) &&
897 		    watermark < BCH_WATERMARK_reclaim) {
898 			ret = bch_err_throw(c, journal_reclaim_would_deadlock);
899 			goto out;
900 		}
901 
902 		ret = drop_locks_do(trans,
903 			bch2_trans_journal_res_get(trans,
904 					(flags & BCH_WATERMARK_MASK)|
905 					JOURNAL_RES_GET_CHECK));
906 		goto out;
907 	}
908 
909 	switch (ret) {
910 	case -BCH_ERR_btree_insert_btree_node_full:
911 		ret = bch2_btree_split_leaf(trans, i->path, flags);
912 		if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
913 			trace_and_count(c, trans_restart_btree_node_split, trans,
914 					trace_ip, trans->paths + i->path);
915 		break;
916 	case -BCH_ERR_btree_insert_need_mark_replicas:
917 		ret = drop_locks_do(trans,
918 			bch2_accounting_update_sb(trans));
919 		break;
920 	case -BCH_ERR_btree_insert_need_journal_reclaim:
921 		bch2_trans_unlock(trans);
922 
923 		trace_and_count(c, trans_blocked_journal_reclaim, trans, trace_ip);
924 		track_event_change(&c->times[BCH_TIME_blocked_key_cache_flush], true);
925 
926 		wait_event_freezable(c->journal.reclaim_wait,
927 				     (ret = journal_reclaim_wait_done(c)));
928 
929 		track_event_change(&c->times[BCH_TIME_blocked_key_cache_flush], false);
930 
931 		if (ret < 0)
932 			break;
933 
934 		ret = bch2_trans_relock(trans);
935 		break;
936 	default:
937 		BUG_ON(ret >= 0);
938 		break;
939 	}
940 out:
941 	BUG_ON(bch2_err_matches(ret, BCH_ERR_transaction_restart) != !!trans->restarted);
942 
943 	bch2_fs_inconsistent_on(bch2_err_matches(ret, ENOSPC) &&
944 				(flags & BCH_TRANS_COMMIT_no_enospc), c,
945 		"%s: incorrectly got %s\n", __func__, bch2_err_str(ret));
946 
947 	return ret;
948 }
949 
950 /*
951  * This is for updates done in the early part of fsck - btree_gc - before we've
952  * gone RW. we only add the new key to the list of keys for journal replay to
953  * do.
954  */
955 static noinline int
956 do_bch2_trans_commit_to_journal_replay(struct btree_trans *trans)
957 {
958 	struct bch_fs *c = trans->c;
959 
960 	BUG_ON(current != c->recovery_task);
961 
962 	trans_for_each_update(trans, i) {
963 		int ret = bch2_journal_key_insert(c, i->btree_id, i->level, i->k);
964 		if (ret)
965 			return ret;
966 	}
967 
968 	for (struct jset_entry *i = btree_trans_journal_entries_start(trans);
969 	     i != btree_trans_journal_entries_top(trans);
970 	     i = vstruct_next(i)) {
971 		if (i->type == BCH_JSET_ENTRY_btree_keys ||
972 		    i->type == BCH_JSET_ENTRY_write_buffer_keys) {
973 			jset_entry_for_each_key(i, k) {
974 				int ret = bch2_journal_key_insert(c, i->btree_id, i->level, k);
975 				if (ret)
976 					return ret;
977 			}
978 		}
979 
980 		if (i->type == BCH_JSET_ENTRY_btree_root) {
981 			guard(mutex)(&c->btree_root_lock);
982 
983 			struct btree_root *r = bch2_btree_id_root(c, i->btree_id);
984 
985 			bkey_copy(&r->key, i->start);
986 			r->level = i->level;
987 			r->alive = true;
988 		}
989 	}
990 
991 	for (struct bkey_i *i = btree_trans_subbuf_base(trans, &trans->accounting);
992 	     i != btree_trans_subbuf_top(trans, &trans->accounting);
993 	     i = bkey_next(i)) {
994 		int ret = bch2_journal_key_insert(c, BTREE_ID_accounting, 0, i);
995 		if (ret)
996 			return ret;
997 	}
998 
999 	return 0;
1000 }
1001 
1002 int __bch2_trans_commit(struct btree_trans *trans, unsigned flags)
1003 {
1004 	struct btree_insert_entry *errored_at = NULL;
1005 	struct bch_fs *c = trans->c;
1006 	int ret = 0;
1007 
1008 	bch2_trans_verify_not_unlocked_or_in_restart(trans);
1009 
1010 	ret = trans_maybe_inject_restart(trans, _RET_IP_);
1011 	if (unlikely(ret))
1012 		goto out_reset;
1013 
1014 	if (!trans->nr_updates &&
1015 	    !trans->journal_entries.u64s &&
1016 	    !trans->accounting.u64s)
1017 		goto out_reset;
1018 
1019 	ret = bch2_trans_commit_run_triggers(trans);
1020 	if (ret)
1021 		goto out_reset;
1022 
1023 	if (!(flags & BCH_TRANS_COMMIT_no_check_rw) &&
1024 	    unlikely(!enumerated_ref_tryget(&c->writes, BCH_WRITE_REF_trans))) {
1025 		if (unlikely(!test_bit(BCH_FS_may_go_rw, &c->flags)))
1026 			ret = do_bch2_trans_commit_to_journal_replay(trans);
1027 		else
1028 			ret = bch_err_throw(c, erofs_trans_commit);
1029 		goto out_reset;
1030 	}
1031 
1032 	EBUG_ON(test_bit(BCH_FS_clean_shutdown, &c->flags));
1033 
1034 	trans->journal_u64s		= trans->journal_entries.u64s + jset_u64s(trans->accounting.u64s);
1035 	trans->journal_transaction_names = READ_ONCE(c->opts.journal_transaction_names);
1036 	if (trans->journal_transaction_names)
1037 		trans->journal_u64s += jset_u64s(JSET_ENTRY_LOG_U64s);
1038 
1039 	trans_for_each_update(trans, i) {
1040 		struct btree_path *path = trans->paths + i->path;
1041 
1042 		EBUG_ON(!path->should_be_locked);
1043 
1044 		ret = bch2_btree_path_upgrade(trans, path, i->level + 1);
1045 		if (unlikely(ret))
1046 			goto out;
1047 
1048 		EBUG_ON(!btree_node_intent_locked(path, i->level));
1049 
1050 		if (i->key_cache_already_flushed)
1051 			continue;
1052 
1053 		if (i->flags & BTREE_UPDATE_nojournal)
1054 			continue;
1055 
1056 		/* we're going to journal the key being updated: */
1057 		trans->journal_u64s += jset_u64s(i->k->k.u64s);
1058 
1059 		/* and we're also going to log the overwrite: */
1060 		if (trans->journal_transaction_names)
1061 			trans->journal_u64s += jset_u64s(i->old_k.u64s);
1062 	}
1063 
1064 	if (trans->extra_disk_res) {
1065 		ret = bch2_disk_reservation_add(c, trans->disk_res,
1066 				trans->extra_disk_res,
1067 				(flags & BCH_TRANS_COMMIT_no_enospc)
1068 				? BCH_DISK_RESERVATION_NOFAIL : 0);
1069 		if (ret)
1070 			goto err;
1071 	}
1072 retry:
1073 	errored_at = NULL;
1074 	bch2_trans_verify_not_unlocked_or_in_restart(trans);
1075 	if (likely(!(flags & BCH_TRANS_COMMIT_no_journal_res)))
1076 		memset(&trans->journal_res, 0, sizeof(trans->journal_res));
1077 	memset(&trans->fs_usage_delta, 0, sizeof(trans->fs_usage_delta));
1078 
1079 	ret = do_bch2_trans_commit(trans, flags, &errored_at, _RET_IP_);
1080 
1081 	/* make sure we didn't drop or screw up locks: */
1082 	bch2_trans_verify_locks(trans);
1083 
1084 	if (ret)
1085 		goto err;
1086 
1087 	trace_and_count(c, transaction_commit, trans, _RET_IP_);
1088 out:
1089 	if (likely(!(flags & BCH_TRANS_COMMIT_no_check_rw)))
1090 		enumerated_ref_put(&c->writes, BCH_WRITE_REF_trans);
1091 out_reset:
1092 	if (!ret)
1093 		bch2_trans_downgrade(trans);
1094 	bch2_trans_reset_updates(trans);
1095 
1096 	return ret;
1097 err:
1098 	ret = bch2_trans_commit_error(trans, flags, errored_at, ret, _RET_IP_);
1099 	if (ret)
1100 		goto out;
1101 
1102 	/*
1103 	 * We might have done another transaction commit in the error path -
1104 	 * i.e. btree write buffer flush - which will have made use of
1105 	 * trans->journal_res, but with BCH_TRANS_COMMIT_no_journal_res that is
1106 	 * how the journal sequence number to pin is passed in - so we must
1107 	 * restart:
1108 	 */
1109 	if (flags & BCH_TRANS_COMMIT_no_journal_res) {
1110 		ret = bch_err_throw(c, transaction_restart_nested);
1111 		goto out;
1112 	}
1113 
1114 	goto retry;
1115 }
1116