xref: /linux/fs/bcachefs/btree_iter.h (revision 576d7fed09c7edbae7600f29a8a3ed6c1ead904f)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _BCACHEFS_BTREE_ITER_H
3 #define _BCACHEFS_BTREE_ITER_H
4 
5 #include "bset.h"
6 #include "btree_types.h"
7 #include "trace.h"
8 
9 static inline int __bkey_err(const struct bkey *k)
10 {
11 	return PTR_ERR_OR_ZERO(k);
12 }
13 
14 #define bkey_err(_k)	__bkey_err((_k).k)
15 
16 static inline void __btree_path_get(struct btree_path *path, bool intent)
17 {
18 	path->ref++;
19 	path->intent_ref += intent;
20 }
21 
22 static inline bool __btree_path_put(struct btree_path *path, bool intent)
23 {
24 	EBUG_ON(!path->ref);
25 	EBUG_ON(!path->intent_ref && intent);
26 	path->intent_ref -= intent;
27 	return --path->ref == 0;
28 }
29 
30 static inline void btree_path_set_dirty(struct btree_path *path,
31 					enum btree_path_uptodate u)
32 {
33 	path->uptodate = max_t(unsigned, path->uptodate, u);
34 }
35 
36 static inline struct btree *btree_path_node(struct btree_path *path,
37 					    unsigned level)
38 {
39 	return level < BTREE_MAX_DEPTH ? path->l[level].b : NULL;
40 }
41 
42 static inline bool btree_node_lock_seq_matches(const struct btree_path *path,
43 					const struct btree *b, unsigned level)
44 {
45 	return path->l[level].lock_seq == six_lock_seq(&b->c.lock);
46 }
47 
48 static inline struct btree *btree_node_parent(struct btree_path *path,
49 					      struct btree *b)
50 {
51 	return btree_path_node(path, b->c.level + 1);
52 }
53 
54 /* Iterate over paths within a transaction: */
55 
56 void __bch2_btree_trans_sort_paths(struct btree_trans *);
57 
58 static inline void btree_trans_sort_paths(struct btree_trans *trans)
59 {
60 	if (!IS_ENABLED(CONFIG_BCACHEFS_DEBUG) &&
61 	    trans->paths_sorted)
62 		return;
63 	__bch2_btree_trans_sort_paths(trans);
64 }
65 
66 static inline struct btree_path *
67 __trans_next_path(struct btree_trans *trans, unsigned idx)
68 {
69 	u64 l;
70 
71 	if (idx == BTREE_ITER_MAX)
72 		return NULL;
73 
74 	l = trans->paths_allocated >> idx;
75 	if (!l)
76 		return NULL;
77 
78 	idx += __ffs64(l);
79 	EBUG_ON(idx >= BTREE_ITER_MAX);
80 	EBUG_ON(trans->paths[idx].idx != idx);
81 	return &trans->paths[idx];
82 }
83 
84 #define trans_for_each_path_from(_trans, _path, _start)			\
85 	for (_path = __trans_next_path((_trans), _start);		\
86 	     (_path);							\
87 	     _path = __trans_next_path((_trans), (_path)->idx + 1))
88 
89 #define trans_for_each_path(_trans, _path)				\
90 	trans_for_each_path_from(_trans, _path, 0)
91 
92 static inline struct btree_path *
93 __trans_next_path_safe(struct btree_trans *trans, unsigned *idx)
94 {
95 	u64 l;
96 
97 	if (*idx == BTREE_ITER_MAX)
98 		return NULL;
99 
100 	l = trans->paths_allocated >> *idx;
101 	if (!l)
102 		return NULL;
103 
104 	*idx += __ffs64(l);
105 	EBUG_ON(*idx >= BTREE_ITER_MAX);
106 	return &trans->paths[*idx];
107 }
108 
109 /*
110  * This version is intended to be safe for use on a btree_trans that is owned by
111  * another thread, for bch2_btree_trans_to_text();
112  */
113 #define trans_for_each_path_safe_from(_trans, _path, _idx, _start)	\
114 	for (_idx = _start;						\
115 	     (_path = __trans_next_path_safe((_trans), &_idx));		\
116 	     _idx++)
117 
118 #define trans_for_each_path_safe(_trans, _path, _idx)			\
119 	trans_for_each_path_safe_from(_trans, _path, _idx, 0)
120 
121 static inline struct btree_path *next_btree_path(struct btree_trans *trans, struct btree_path *path)
122 {
123 	unsigned idx = path ? path->sorted_idx + 1 : 0;
124 
125 	EBUG_ON(idx > trans->nr_sorted);
126 
127 	return idx < trans->nr_sorted
128 		? trans->paths + trans->sorted[idx]
129 		: NULL;
130 }
131 
132 static inline struct btree_path *prev_btree_path(struct btree_trans *trans, struct btree_path *path)
133 {
134 	unsigned idx = path ? path->sorted_idx : trans->nr_sorted;
135 
136 	return idx
137 		? trans->paths + trans->sorted[idx - 1]
138 		: NULL;
139 }
140 
141 #define trans_for_each_path_inorder(_trans, _path, _i)			\
142 	for (_i = 0;							\
143 	     ((_path) = (_trans)->paths + trans->sorted[_i]), (_i) < (_trans)->nr_sorted;\
144 	     _i++)
145 
146 #define trans_for_each_path_inorder_reverse(_trans, _path, _i)		\
147 	for (_i = trans->nr_sorted - 1;					\
148 	     ((_path) = (_trans)->paths + trans->sorted[_i]), (_i) >= 0;\
149 	     --_i)
150 
151 static inline bool __path_has_node(const struct btree_path *path,
152 				   const struct btree *b)
153 {
154 	return path->l[b->c.level].b == b &&
155 		btree_node_lock_seq_matches(path, b, b->c.level);
156 }
157 
158 static inline struct btree_path *
159 __trans_next_path_with_node(struct btree_trans *trans, struct btree *b,
160 			    unsigned idx)
161 {
162 	struct btree_path *path = __trans_next_path(trans, idx);
163 
164 	while (path && !__path_has_node(path, b))
165 		path = __trans_next_path(trans, path->idx + 1);
166 
167 	return path;
168 }
169 
170 #define trans_for_each_path_with_node(_trans, _b, _path)		\
171 	for (_path = __trans_next_path_with_node((_trans), (_b), 0);	\
172 	     (_path);							\
173 	     _path = __trans_next_path_with_node((_trans), (_b),	\
174 						 (_path)->idx + 1))
175 
176 struct btree_path *__bch2_btree_path_make_mut(struct btree_trans *, struct btree_path *,
177 			 bool, unsigned long);
178 
179 static inline struct btree_path * __must_check
180 bch2_btree_path_make_mut(struct btree_trans *trans,
181 			 struct btree_path *path, bool intent,
182 			 unsigned long ip)
183 {
184 	if (path->ref > 1 || path->preserve)
185 		path = __bch2_btree_path_make_mut(trans, path, intent, ip);
186 	path->should_be_locked = false;
187 	return path;
188 }
189 
190 struct btree_path * __must_check
191 __bch2_btree_path_set_pos(struct btree_trans *, struct btree_path *,
192 			struct bpos, bool, unsigned long, int);
193 
194 static inline struct btree_path * __must_check
195 bch2_btree_path_set_pos(struct btree_trans *trans,
196 		   struct btree_path *path, struct bpos new_pos,
197 		   bool intent, unsigned long ip)
198 {
199 	int cmp = bpos_cmp(new_pos, path->pos);
200 
201 	return cmp
202 		? __bch2_btree_path_set_pos(trans, path, new_pos, intent, ip, cmp)
203 		: path;
204 }
205 
206 int __must_check bch2_btree_path_traverse_one(struct btree_trans *, struct btree_path *,
207 					      unsigned, unsigned long);
208 
209 static inline int __must_check bch2_btree_path_traverse(struct btree_trans *trans,
210 					  struct btree_path *path, unsigned flags)
211 {
212 	if (path->uptodate < BTREE_ITER_NEED_RELOCK)
213 		return 0;
214 
215 	return bch2_btree_path_traverse_one(trans, path, flags, _RET_IP_);
216 }
217 
218 int __must_check bch2_btree_path_traverse(struct btree_trans *,
219 					  struct btree_path *, unsigned);
220 struct btree_path *bch2_path_get(struct btree_trans *, enum btree_id, struct bpos,
221 				 unsigned, unsigned, unsigned, unsigned long);
222 struct bkey_s_c bch2_btree_path_peek_slot(struct btree_path *, struct bkey *);
223 
224 /*
225  * bch2_btree_path_peek_slot() for a cached iterator might return a key in a
226  * different snapshot:
227  */
228 static inline struct bkey_s_c bch2_btree_path_peek_slot_exact(struct btree_path *path, struct bkey *u)
229 {
230 	struct bkey_s_c k = bch2_btree_path_peek_slot(path, u);
231 
232 	if (k.k && bpos_eq(path->pos, k.k->p))
233 		return k;
234 
235 	bkey_init(u);
236 	u->p = path->pos;
237 	return (struct bkey_s_c) { u, NULL };
238 }
239 
240 struct bkey_i *bch2_btree_journal_peek_slot(struct btree_trans *,
241 					struct btree_iter *, struct bpos);
242 
243 void bch2_btree_path_level_init(struct btree_trans *, struct btree_path *, struct btree *);
244 
245 int __bch2_trans_mutex_lock(struct btree_trans *, struct mutex *);
246 
247 static inline int bch2_trans_mutex_lock(struct btree_trans *trans, struct mutex *lock)
248 {
249 	return mutex_trylock(lock)
250 		? 0
251 		: __bch2_trans_mutex_lock(trans, lock);
252 }
253 
254 #ifdef CONFIG_BCACHEFS_DEBUG
255 void bch2_trans_verify_paths(struct btree_trans *);
256 void bch2_assert_pos_locked(struct btree_trans *, enum btree_id,
257 			    struct bpos, bool);
258 #else
259 static inline void bch2_trans_verify_paths(struct btree_trans *trans) {}
260 static inline void bch2_assert_pos_locked(struct btree_trans *trans, enum btree_id id,
261 					  struct bpos pos, bool key_cache) {}
262 #endif
263 
264 void bch2_btree_path_fix_key_modified(struct btree_trans *trans,
265 				      struct btree *, struct bkey_packed *);
266 void bch2_btree_node_iter_fix(struct btree_trans *trans, struct btree_path *,
267 			      struct btree *, struct btree_node_iter *,
268 			      struct bkey_packed *, unsigned, unsigned);
269 
270 int bch2_btree_path_relock_intent(struct btree_trans *, struct btree_path *);
271 
272 void bch2_path_put(struct btree_trans *, struct btree_path *, bool);
273 
274 int bch2_trans_relock(struct btree_trans *);
275 int bch2_trans_relock_notrace(struct btree_trans *);
276 void bch2_trans_unlock(struct btree_trans *);
277 void bch2_trans_unlock_long(struct btree_trans *);
278 bool bch2_trans_locked(struct btree_trans *);
279 
280 static inline int trans_was_restarted(struct btree_trans *trans, u32 restart_count)
281 {
282 	return restart_count != trans->restart_count
283 		? -BCH_ERR_transaction_restart_nested
284 		: 0;
285 }
286 
287 void __noreturn bch2_trans_restart_error(struct btree_trans *, u32);
288 
289 static inline void bch2_trans_verify_not_restarted(struct btree_trans *trans,
290 						   u32 restart_count)
291 {
292 	if (trans_was_restarted(trans, restart_count))
293 		bch2_trans_restart_error(trans, restart_count);
294 }
295 
296 void __noreturn bch2_trans_in_restart_error(struct btree_trans *);
297 
298 static inline void bch2_trans_verify_not_in_restart(struct btree_trans *trans)
299 {
300 	if (trans->restarted)
301 		bch2_trans_in_restart_error(trans);
302 }
303 
304 __always_inline
305 static int btree_trans_restart_nounlock(struct btree_trans *trans, int err)
306 {
307 	BUG_ON(err <= 0);
308 	BUG_ON(!bch2_err_matches(-err, BCH_ERR_transaction_restart));
309 
310 	trans->restarted = err;
311 	trans->last_restarted_ip = _THIS_IP_;
312 	return -err;
313 }
314 
315 __always_inline
316 static int btree_trans_restart(struct btree_trans *trans, int err)
317 {
318 	btree_trans_restart_nounlock(trans, err);
319 	return -err;
320 }
321 
322 bool bch2_btree_node_upgrade(struct btree_trans *,
323 			     struct btree_path *, unsigned);
324 
325 void __bch2_btree_path_downgrade(struct btree_trans *, struct btree_path *, unsigned);
326 
327 static inline void bch2_btree_path_downgrade(struct btree_trans *trans,
328 					     struct btree_path *path)
329 {
330 	unsigned new_locks_want = path->level + !!path->intent_ref;
331 
332 	if (path->locks_want > new_locks_want)
333 		__bch2_btree_path_downgrade(trans, path, new_locks_want);
334 }
335 
336 void bch2_trans_downgrade(struct btree_trans *);
337 
338 void bch2_trans_node_add(struct btree_trans *trans, struct btree *);
339 void bch2_trans_node_reinit_iter(struct btree_trans *, struct btree *);
340 
341 int __must_check __bch2_btree_iter_traverse(struct btree_iter *iter);
342 int __must_check bch2_btree_iter_traverse(struct btree_iter *);
343 
344 struct btree *bch2_btree_iter_peek_node(struct btree_iter *);
345 struct btree *bch2_btree_iter_peek_node_and_restart(struct btree_iter *);
346 struct btree *bch2_btree_iter_next_node(struct btree_iter *);
347 
348 struct bkey_s_c bch2_btree_iter_peek_upto(struct btree_iter *, struct bpos);
349 struct bkey_s_c bch2_btree_iter_next(struct btree_iter *);
350 
351 struct bkey_s_c bch2_btree_iter_peek_all_levels(struct btree_iter *);
352 
353 static inline struct bkey_s_c bch2_btree_iter_peek(struct btree_iter *iter)
354 {
355 	return bch2_btree_iter_peek_upto(iter, SPOS_MAX);
356 }
357 
358 struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *);
359 struct bkey_s_c bch2_btree_iter_prev(struct btree_iter *);
360 
361 struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *);
362 struct bkey_s_c bch2_btree_iter_next_slot(struct btree_iter *);
363 struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_iter *);
364 
365 bool bch2_btree_iter_advance(struct btree_iter *);
366 bool bch2_btree_iter_rewind(struct btree_iter *);
367 
368 static inline void __bch2_btree_iter_set_pos(struct btree_iter *iter, struct bpos new_pos)
369 {
370 	iter->k.type = KEY_TYPE_deleted;
371 	iter->k.p.inode		= iter->pos.inode	= new_pos.inode;
372 	iter->k.p.offset	= iter->pos.offset	= new_pos.offset;
373 	iter->k.p.snapshot	= iter->pos.snapshot	= new_pos.snapshot;
374 	iter->k.size = 0;
375 }
376 
377 static inline void bch2_btree_iter_set_pos(struct btree_iter *iter, struct bpos new_pos)
378 {
379 	if (unlikely(iter->update_path))
380 		bch2_path_put(iter->trans, iter->update_path,
381 			      iter->flags & BTREE_ITER_INTENT);
382 	iter->update_path = NULL;
383 
384 	if (!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS))
385 		new_pos.snapshot = iter->snapshot;
386 
387 	__bch2_btree_iter_set_pos(iter, new_pos);
388 }
389 
390 static inline void bch2_btree_iter_set_pos_to_extent_start(struct btree_iter *iter)
391 {
392 	BUG_ON(!(iter->flags & BTREE_ITER_IS_EXTENTS));
393 	iter->pos = bkey_start_pos(&iter->k);
394 }
395 
396 static inline void bch2_btree_iter_set_snapshot(struct btree_iter *iter, u32 snapshot)
397 {
398 	struct bpos pos = iter->pos;
399 
400 	iter->snapshot = snapshot;
401 	pos.snapshot = snapshot;
402 	bch2_btree_iter_set_pos(iter, pos);
403 }
404 
405 void bch2_trans_iter_exit(struct btree_trans *, struct btree_iter *);
406 
407 static inline unsigned __bch2_btree_iter_flags(struct btree_trans *trans,
408 					       unsigned btree_id,
409 					       unsigned flags)
410 {
411 	if (flags & BTREE_ITER_ALL_LEVELS)
412 		flags |= BTREE_ITER_ALL_SNAPSHOTS|__BTREE_ITER_ALL_SNAPSHOTS;
413 
414 	if (!(flags & (BTREE_ITER_ALL_SNAPSHOTS|BTREE_ITER_NOT_EXTENTS)) &&
415 	    btree_id_is_extents(btree_id))
416 		flags |= BTREE_ITER_IS_EXTENTS;
417 
418 	if (!(flags & __BTREE_ITER_ALL_SNAPSHOTS) &&
419 	    !btree_type_has_snapshot_field(btree_id))
420 		flags &= ~BTREE_ITER_ALL_SNAPSHOTS;
421 
422 	if (!(flags & BTREE_ITER_ALL_SNAPSHOTS) &&
423 	    btree_type_has_snapshots(btree_id))
424 		flags |= BTREE_ITER_FILTER_SNAPSHOTS;
425 
426 	if (trans->journal_replay_not_finished)
427 		flags |= BTREE_ITER_WITH_JOURNAL;
428 
429 	return flags;
430 }
431 
432 static inline unsigned bch2_btree_iter_flags(struct btree_trans *trans,
433 					     unsigned btree_id,
434 					     unsigned flags)
435 {
436 	if (!btree_id_cached(trans->c, btree_id)) {
437 		flags &= ~BTREE_ITER_CACHED;
438 		flags &= ~BTREE_ITER_WITH_KEY_CACHE;
439 	} else if (!(flags & BTREE_ITER_CACHED))
440 		flags |= BTREE_ITER_WITH_KEY_CACHE;
441 
442 	return __bch2_btree_iter_flags(trans, btree_id, flags);
443 }
444 
445 static inline void bch2_trans_iter_init_common(struct btree_trans *trans,
446 					  struct btree_iter *iter,
447 					  unsigned btree_id, struct bpos pos,
448 					  unsigned locks_want,
449 					  unsigned depth,
450 					  unsigned flags,
451 					  unsigned long ip)
452 {
453 	memset(iter, 0, sizeof(*iter));
454 	iter->trans	= trans;
455 	iter->btree_id	= btree_id;
456 	iter->flags	= flags;
457 	iter->snapshot	= pos.snapshot;
458 	iter->pos	= pos;
459 	iter->k.p	= pos;
460 
461 #ifdef CONFIG_BCACHEFS_DEBUG
462 	iter->ip_allocated = ip;
463 #endif
464 	iter->path = bch2_path_get(trans, btree_id, iter->pos,
465 				   locks_want, depth, flags, ip);
466 }
467 
468 void bch2_trans_iter_init_outlined(struct btree_trans *, struct btree_iter *,
469 			  enum btree_id, struct bpos, unsigned);
470 
471 static inline void bch2_trans_iter_init(struct btree_trans *trans,
472 			  struct btree_iter *iter,
473 			  unsigned btree_id, struct bpos pos,
474 			  unsigned flags)
475 {
476 	if (__builtin_constant_p(btree_id) &&
477 	    __builtin_constant_p(flags))
478 		bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0,
479 				bch2_btree_iter_flags(trans, btree_id, flags),
480 				_THIS_IP_);
481 	else
482 		bch2_trans_iter_init_outlined(trans, iter, btree_id, pos, flags);
483 }
484 
485 void bch2_trans_node_iter_init(struct btree_trans *, struct btree_iter *,
486 			       enum btree_id, struct bpos,
487 			       unsigned, unsigned, unsigned);
488 void bch2_trans_copy_iter(struct btree_iter *, struct btree_iter *);
489 
490 static inline void set_btree_iter_dontneed(struct btree_iter *iter)
491 {
492 	if (!iter->trans->restarted)
493 		iter->path->preserve = false;
494 }
495 
496 void *__bch2_trans_kmalloc(struct btree_trans *, size_t);
497 
498 static inline void *bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
499 {
500 	size = roundup(size, 8);
501 
502 	if (likely(trans->mem_top + size <= trans->mem_bytes)) {
503 		void *p = trans->mem + trans->mem_top;
504 
505 		trans->mem_top += size;
506 		memset(p, 0, size);
507 		return p;
508 	} else {
509 		return __bch2_trans_kmalloc(trans, size);
510 	}
511 }
512 
513 static inline void *bch2_trans_kmalloc_nomemzero(struct btree_trans *trans, size_t size)
514 {
515 	size = roundup(size, 8);
516 
517 	if (likely(trans->mem_top + size <= trans->mem_bytes)) {
518 		void *p = trans->mem + trans->mem_top;
519 
520 		trans->mem_top += size;
521 		return p;
522 	} else {
523 		return __bch2_trans_kmalloc(trans, size);
524 	}
525 }
526 
527 static inline struct bkey_s_c __bch2_bkey_get_iter(struct btree_trans *trans,
528 				struct btree_iter *iter,
529 				unsigned btree_id, struct bpos pos,
530 				unsigned flags, unsigned type)
531 {
532 	struct bkey_s_c k;
533 
534 	bch2_trans_iter_init(trans, iter, btree_id, pos, flags);
535 	k = bch2_btree_iter_peek_slot(iter);
536 
537 	if (!bkey_err(k) && type && k.k->type != type)
538 		k = bkey_s_c_err(-BCH_ERR_ENOENT_bkey_type_mismatch);
539 	if (unlikely(bkey_err(k)))
540 		bch2_trans_iter_exit(trans, iter);
541 	return k;
542 }
543 
544 static inline struct bkey_s_c bch2_bkey_get_iter(struct btree_trans *trans,
545 				struct btree_iter *iter,
546 				unsigned btree_id, struct bpos pos,
547 				unsigned flags)
548 {
549 	return __bch2_bkey_get_iter(trans, iter, btree_id, pos, flags, 0);
550 }
551 
552 #define bch2_bkey_get_iter_typed(_trans, _iter, _btree_id, _pos, _flags, _type)\
553 	bkey_s_c_to_##_type(__bch2_bkey_get_iter(_trans, _iter,			\
554 				       _btree_id, _pos, _flags, KEY_TYPE_##_type))
555 
556 static inline int __bch2_bkey_get_val_typed(struct btree_trans *trans,
557 				unsigned btree_id, struct bpos pos,
558 				unsigned flags, unsigned type,
559 				unsigned val_size, void *val)
560 {
561 	struct btree_iter iter;
562 	struct bkey_s_c k;
563 	int ret;
564 
565 	k = __bch2_bkey_get_iter(trans, &iter, btree_id, pos, flags, type);
566 	ret = bkey_err(k);
567 	if (!ret) {
568 		unsigned b = min_t(unsigned, bkey_val_bytes(k.k), val_size);
569 
570 		memcpy(val, k.v, b);
571 		if (unlikely(b < sizeof(*val)))
572 			memset((void *) val + b, 0, sizeof(*val) - b);
573 		bch2_trans_iter_exit(trans, &iter);
574 	}
575 
576 	return ret;
577 }
578 
579 #define bch2_bkey_get_val_typed(_trans, _btree_id, _pos, _flags, _type, _val)\
580 	__bch2_bkey_get_val_typed(_trans, _btree_id, _pos, _flags,	\
581 				  KEY_TYPE_##_type, sizeof(*_val), _val)
582 
583 void bch2_trans_srcu_unlock(struct btree_trans *);
584 void bch2_trans_srcu_lock(struct btree_trans *);
585 
586 u32 bch2_trans_begin(struct btree_trans *);
587 
588 /*
589  * XXX
590  * this does not handle transaction restarts from bch2_btree_iter_next_node()
591  * correctly
592  */
593 #define __for_each_btree_node(_trans, _iter, _btree_id, _start,		\
594 			      _locks_want, _depth, _flags, _b, _ret)	\
595 	for (bch2_trans_node_iter_init((_trans), &(_iter), (_btree_id),	\
596 				_start, _locks_want, _depth, _flags);	\
597 	     (_b) = bch2_btree_iter_peek_node_and_restart(&(_iter)),	\
598 	     !((_ret) = PTR_ERR_OR_ZERO(_b)) && (_b);			\
599 	     (_b) = bch2_btree_iter_next_node(&(_iter)))
600 
601 #define for_each_btree_node(_trans, _iter, _btree_id, _start,		\
602 			    _flags, _b, _ret)				\
603 	__for_each_btree_node(_trans, _iter, _btree_id, _start,		\
604 			      0, 0, _flags, _b, _ret)
605 
606 static inline struct bkey_s_c bch2_btree_iter_peek_prev_type(struct btree_iter *iter,
607 							     unsigned flags)
608 {
609 	BUG_ON(flags & BTREE_ITER_ALL_LEVELS);
610 
611 	return  flags & BTREE_ITER_SLOTS      ? bch2_btree_iter_peek_slot(iter) :
612 						bch2_btree_iter_peek_prev(iter);
613 }
614 
615 static inline struct bkey_s_c bch2_btree_iter_peek_type(struct btree_iter *iter,
616 							unsigned flags)
617 {
618 	return  flags & BTREE_ITER_ALL_LEVELS ? bch2_btree_iter_peek_all_levels(iter) :
619 		flags & BTREE_ITER_SLOTS      ? bch2_btree_iter_peek_slot(iter) :
620 						bch2_btree_iter_peek(iter);
621 }
622 
623 static inline struct bkey_s_c bch2_btree_iter_peek_upto_type(struct btree_iter *iter,
624 							     struct bpos end,
625 							     unsigned flags)
626 {
627 	if (!(flags & BTREE_ITER_SLOTS))
628 		return bch2_btree_iter_peek_upto(iter, end);
629 
630 	if (bkey_gt(iter->pos, end))
631 		return bkey_s_c_null;
632 
633 	return bch2_btree_iter_peek_slot(iter);
634 }
635 
636 static inline int btree_trans_too_many_iters(struct btree_trans *trans)
637 {
638 	if (hweight64(trans->paths_allocated) > BTREE_ITER_MAX - 8) {
639 		trace_and_count(trans->c, trans_restart_too_many_iters, trans, _THIS_IP_);
640 		return btree_trans_restart(trans, BCH_ERR_transaction_restart_too_many_iters);
641 	}
642 
643 	return 0;
644 }
645 
646 struct bkey_s_c bch2_btree_iter_peek_and_restart_outlined(struct btree_iter *);
647 
648 static inline struct bkey_s_c
649 __bch2_btree_iter_peek_and_restart(struct btree_trans *trans,
650 				   struct btree_iter *iter, unsigned flags)
651 {
652 	struct bkey_s_c k;
653 
654 	while (btree_trans_too_many_iters(trans) ||
655 	       (k = bch2_btree_iter_peek_type(iter, flags),
656 		bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart)))
657 		bch2_trans_begin(trans);
658 
659 	return k;
660 }
661 
662 static inline struct bkey_s_c
663 __bch2_btree_iter_peek_upto_and_restart(struct btree_trans *trans,
664 					struct btree_iter *iter,
665 					struct bpos end,
666 					unsigned flags)
667 {
668 	struct bkey_s_c k;
669 
670 	while (btree_trans_too_many_iters(trans) ||
671 	       (k = bch2_btree_iter_peek_upto_type(iter, end, flags),
672 		bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart)))
673 		bch2_trans_begin(trans);
674 
675 	return k;
676 }
677 
678 #define lockrestart_do(_trans, _do)					\
679 ({									\
680 	u32 _restart_count;						\
681 	int _ret2;							\
682 									\
683 	do {								\
684 		_restart_count = bch2_trans_begin(_trans);		\
685 		_ret2 = (_do);						\
686 	} while (bch2_err_matches(_ret2, BCH_ERR_transaction_restart));	\
687 									\
688 	if (!_ret2)							\
689 		bch2_trans_verify_not_restarted(_trans, _restart_count);\
690 									\
691 	_ret2;								\
692 })
693 
694 /*
695  * nested_lockrestart_do(), nested_commit_do():
696  *
697  * These are like lockrestart_do() and commit_do(), with two differences:
698  *
699  *  - We don't call bch2_trans_begin() unless we had a transaction restart
700  *  - We return -BCH_ERR_transaction_restart_nested if we succeeded after a
701  *  transaction restart
702  */
703 #define nested_lockrestart_do(_trans, _do)				\
704 ({									\
705 	u32 _restart_count, _orig_restart_count;			\
706 	int _ret2;							\
707 									\
708 	_restart_count = _orig_restart_count = (_trans)->restart_count;	\
709 									\
710 	while (bch2_err_matches(_ret2 = (_do), BCH_ERR_transaction_restart))\
711 		_restart_count = bch2_trans_begin(_trans);		\
712 									\
713 	if (!_ret2)							\
714 		bch2_trans_verify_not_restarted(_trans, _restart_count);\
715 									\
716 	_ret2 ?: trans_was_restarted(_trans, _restart_count);		\
717 })
718 
719 #define for_each_btree_key2(_trans, _iter, _btree_id,			\
720 			    _start, _flags, _k, _do)			\
721 ({									\
722 	int _ret3 = 0;							\
723 									\
724 	bch2_trans_iter_init((_trans), &(_iter), (_btree_id),		\
725 			     (_start), (_flags));			\
726 									\
727 	while (1) {							\
728 		u32 _restart_count = bch2_trans_begin(_trans);		\
729 									\
730 		_ret3 = 0;						\
731 		(_k) = bch2_btree_iter_peek_type(&(_iter), (_flags));	\
732 		if (!(_k).k)						\
733 			break;						\
734 									\
735 		_ret3 = bkey_err(_k) ?: (_do);				\
736 		if (bch2_err_matches(_ret3, BCH_ERR_transaction_restart))\
737 			continue;					\
738 		if (_ret3)						\
739 			break;						\
740 		bch2_trans_verify_not_restarted(_trans, _restart_count);\
741 		if (!bch2_btree_iter_advance(&(_iter)))			\
742 			break;						\
743 	}								\
744 									\
745 	bch2_trans_iter_exit((_trans), &(_iter));			\
746 	_ret3;								\
747 })
748 
749 #define for_each_btree_key2_upto(_trans, _iter, _btree_id,		\
750 			    _start, _end, _flags, _k, _do)		\
751 ({									\
752 	int _ret3 = 0;							\
753 									\
754 	bch2_trans_iter_init((_trans), &(_iter), (_btree_id),		\
755 			     (_start), (_flags));			\
756 									\
757 	while (1) {							\
758 		u32 _restart_count = bch2_trans_begin(_trans);		\
759 									\
760 		_ret3 = 0;						\
761 		(_k) = bch2_btree_iter_peek_upto_type(&(_iter), _end, (_flags));\
762 		if (!(_k).k)						\
763 			break;						\
764 									\
765 		_ret3 = bkey_err(_k) ?: (_do);				\
766 		if (bch2_err_matches(_ret3, BCH_ERR_transaction_restart))\
767 			continue;					\
768 		if (_ret3)						\
769 			break;						\
770 		bch2_trans_verify_not_restarted(_trans, _restart_count);\
771 		if (!bch2_btree_iter_advance(&(_iter)))			\
772 			break;						\
773 	}								\
774 									\
775 	bch2_trans_iter_exit((_trans), &(_iter));			\
776 	_ret3;								\
777 })
778 
779 #define for_each_btree_key_reverse(_trans, _iter, _btree_id,		\
780 				   _start, _flags, _k, _do)		\
781 ({									\
782 	int _ret3 = 0;							\
783 									\
784 	bch2_trans_iter_init((_trans), &(_iter), (_btree_id),		\
785 			     (_start), (_flags));			\
786 									\
787 	while (1) {							\
788 		u32 _restart_count = bch2_trans_begin(_trans);		\
789 		(_k) = bch2_btree_iter_peek_prev_type(&(_iter), (_flags));\
790 		if (!(_k).k) {						\
791 			_ret3 = 0;					\
792 			break;						\
793 		}							\
794 									\
795 		_ret3 = bkey_err(_k) ?: (_do);				\
796 		if (bch2_err_matches(_ret3, BCH_ERR_transaction_restart))\
797 			continue;					\
798 		if (_ret3)						\
799 			break;						\
800 		bch2_trans_verify_not_restarted(_trans, _restart_count);\
801 		if (!bch2_btree_iter_rewind(&(_iter)))			\
802 			break;						\
803 	}								\
804 									\
805 	bch2_trans_iter_exit((_trans), &(_iter));			\
806 	_ret3;								\
807 })
808 
809 #define for_each_btree_key_commit(_trans, _iter, _btree_id,		\
810 				  _start, _iter_flags, _k,		\
811 				  _disk_res, _journal_seq, _commit_flags,\
812 				  _do)					\
813 	for_each_btree_key2(_trans, _iter, _btree_id, _start, _iter_flags, _k,\
814 			    (_do) ?: bch2_trans_commit(_trans, (_disk_res),\
815 					(_journal_seq), (_commit_flags)))
816 
817 #define for_each_btree_key_reverse_commit(_trans, _iter, _btree_id,	\
818 				  _start, _iter_flags, _k,		\
819 				  _disk_res, _journal_seq, _commit_flags,\
820 				  _do)					\
821 	for_each_btree_key_reverse(_trans, _iter, _btree_id, _start, _iter_flags, _k,\
822 			    (_do) ?: bch2_trans_commit(_trans, (_disk_res),\
823 					(_journal_seq), (_commit_flags)))
824 
825 #define for_each_btree_key_upto_commit(_trans, _iter, _btree_id,	\
826 				  _start, _end, _iter_flags, _k,	\
827 				  _disk_res, _journal_seq, _commit_flags,\
828 				  _do)					\
829 	for_each_btree_key2_upto(_trans, _iter, _btree_id, _start, _end, _iter_flags, _k,\
830 			    (_do) ?: bch2_trans_commit(_trans, (_disk_res),\
831 					(_journal_seq), (_commit_flags)))
832 
833 #define for_each_btree_key(_trans, _iter, _btree_id,			\
834 			   _start, _flags, _k, _ret)			\
835 	for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),	\
836 				  (_start), (_flags));			\
837 	     (_k) = __bch2_btree_iter_peek_and_restart((_trans), &(_iter), _flags),\
838 	     !((_ret) = bkey_err(_k)) && (_k).k;			\
839 	     bch2_btree_iter_advance(&(_iter)))
840 
841 #define for_each_btree_key_upto(_trans, _iter, _btree_id,		\
842 				_start, _end, _flags, _k, _ret)		\
843 	for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),	\
844 				  (_start), (_flags));			\
845 	     (_k) = __bch2_btree_iter_peek_upto_and_restart((_trans),	\
846 						&(_iter), _end, _flags),\
847 	     !((_ret) = bkey_err(_k)) && (_k).k;			\
848 	     bch2_btree_iter_advance(&(_iter)))
849 
850 #define for_each_btree_key_norestart(_trans, _iter, _btree_id,		\
851 			   _start, _flags, _k, _ret)			\
852 	for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),	\
853 				  (_start), (_flags));			\
854 	     (_k) = bch2_btree_iter_peek_type(&(_iter), _flags),	\
855 	     !((_ret) = bkey_err(_k)) && (_k).k;			\
856 	     bch2_btree_iter_advance(&(_iter)))
857 
858 #define for_each_btree_key_upto_norestart(_trans, _iter, _btree_id,	\
859 			   _start, _end, _flags, _k, _ret)		\
860 	for (bch2_trans_iter_init((_trans), &(_iter), (_btree_id),	\
861 				  (_start), (_flags));			\
862 	     (_k) = bch2_btree_iter_peek_upto_type(&(_iter), _end, _flags),\
863 	     !((_ret) = bkey_err(_k)) && (_k).k;			\
864 	     bch2_btree_iter_advance(&(_iter)))
865 
866 #define for_each_btree_key_continue(_trans, _iter, _flags, _k, _ret)	\
867 	for (;								\
868 	     (_k) = __bch2_btree_iter_peek_and_restart((_trans), &(_iter), _flags),\
869 	     !((_ret) = bkey_err(_k)) && (_k).k;			\
870 	     bch2_btree_iter_advance(&(_iter)))
871 
872 #define for_each_btree_key_continue_norestart(_iter, _flags, _k, _ret)	\
873 	for (;								\
874 	     (_k) = bch2_btree_iter_peek_type(&(_iter), _flags),	\
875 	     !((_ret) = bkey_err(_k)) && (_k).k;			\
876 	     bch2_btree_iter_advance(&(_iter)))
877 
878 #define for_each_btree_key_upto_continue_norestart(_iter, _end, _flags, _k, _ret)\
879 	for (;									\
880 	     (_k) = bch2_btree_iter_peek_upto_type(&(_iter), _end, _flags),	\
881 	     !((_ret) = bkey_err(_k)) && (_k).k;				\
882 	     bch2_btree_iter_advance(&(_iter)))
883 
884 #define drop_locks_do(_trans, _do)					\
885 ({									\
886 	bch2_trans_unlock(_trans);					\
887 	_do ?: bch2_trans_relock(_trans);				\
888 })
889 
890 #define allocate_dropping_locks_errcode(_trans, _do)			\
891 ({									\
892 	gfp_t _gfp = GFP_NOWAIT|__GFP_NOWARN;				\
893 	int _ret = _do;							\
894 									\
895 	if (bch2_err_matches(_ret, ENOMEM)) {				\
896 		_gfp = GFP_KERNEL;					\
897 		_ret = drop_locks_do(trans, _do);			\
898 	}								\
899 	_ret;								\
900 })
901 
902 #define allocate_dropping_locks(_trans, _ret, _do)			\
903 ({									\
904 	gfp_t _gfp = GFP_NOWAIT|__GFP_NOWARN;				\
905 	typeof(_do) _p = _do;						\
906 									\
907 	_ret = 0;							\
908 	if (unlikely(!_p)) {						\
909 		_gfp = GFP_KERNEL;					\
910 		_ret = drop_locks_do(trans, ((_p = _do), 0));		\
911 	}								\
912 	_p;								\
913 })
914 
915 /* new multiple iterator interface: */
916 
917 void bch2_trans_updates_to_text(struct printbuf *, struct btree_trans *);
918 void bch2_btree_path_to_text(struct printbuf *, struct btree_path *);
919 void bch2_trans_paths_to_text(struct printbuf *, struct btree_trans *);
920 void bch2_dump_trans_updates(struct btree_trans *);
921 void bch2_dump_trans_paths_updates(struct btree_trans *);
922 
923 struct btree_trans *__bch2_trans_get(struct bch_fs *, unsigned);
924 void bch2_trans_put(struct btree_trans *);
925 
926 extern const char *bch2_btree_transaction_fns[BCH_TRANSACTIONS_NR];
927 unsigned bch2_trans_get_fn_idx(const char *);
928 
929 #define bch2_trans_get(_c)						\
930 ({									\
931 	static unsigned trans_fn_idx;					\
932 									\
933 	if (unlikely(!trans_fn_idx))					\
934 		trans_fn_idx = bch2_trans_get_fn_idx(__func__);		\
935 	__bch2_trans_get(_c, trans_fn_idx);				\
936 })
937 
938 void bch2_btree_trans_to_text(struct printbuf *, struct btree_trans *);
939 
940 void bch2_fs_btree_iter_exit(struct bch_fs *);
941 int bch2_fs_btree_iter_init(struct bch_fs *);
942 
943 #endif /* _BCACHEFS_BTREE_ITER_H */
944