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bcachefs: Drop journal entry compaction
[linux-block.git] / fs / bcachefs / btree_iter.c
CommitLineData
1c6fdbd8
KO		 1// SPDX-License-Identifier: GPL-2.0
2
3#include "bcachefs.h"
4#include "bkey_methods.h"
07a1006a 5#include "bkey_buf.h"
1c6fdbd8
KO		 6#include "btree_cache.h"
7#include "btree_iter.h"
401585fe 8#include "btree_journal_iter.h"
2ca88e5a 9#include "btree_key_cache.h"
1c6fdbd8 10#include "btree_locking.h"
57b0b3db 11#include "btree_update.h"
1c6fdbd8 12#include "debug.h"
50dc0f69 13#include "error.h"
1c6fdbd8 14#include "extents.h"
2ca88e5a 15#include "journal.h"
67997234 16#include "journal_io.h"
35d5aff2 17#include "replicas.h"
8e877caa 18#include "snapshot.h"
1c6fdbd8
KO		 19#include "trace.h"
20
a0cb8d78 21#include <linux/random.h>
1c6fdbd8
KO		 22#include <linux/prefetch.h>
23
67e0dd8f
KO		 24static inline void btree_path_list_remove(struct btree_trans *, struct btree_path *);
25static inline void btree_path_list_add(struct btree_trans *, struct btree_path *,
26 struct btree_path *);
27
ee2c6ea7
KO		 28static inline unsigned long btree_iter_ip_allocated(struct btree_iter *iter)
29{
94c69faf 30#ifdef TRACK_PATH_ALLOCATED
ee2c6ea7
KO		 31 return iter->ip_allocated;
32#else
33 return 0;
34#endif
35}
36
67e0dd8f
KO		 37static struct btree_path *btree_path_alloc(struct btree_trans *, struct btree_path *);
38
39static inline int __btree_path_cmp(const struct btree_path *l,
40 enum btree_id r_btree_id,
41 bool r_cached,
42 struct bpos r_pos,
43 unsigned r_level)
0423fb71 44{
7abda8c1
KO		 45 /*
46 * Must match lock ordering as defined by __bch2_btree_node_lock:
47 */
67e0dd8f 48 return cmp_int(l->btree_id, r_btree_id) ?:
32b26e8c 49 cmp_int((int) l->cached, (int) r_cached) ?:
67e0dd8f
KO		 50 bpos_cmp(l->pos, r_pos) ?:
51 -cmp_int(l->level, r_level);
52}
53
54static inline int btree_path_cmp(const struct btree_path *l,
55 const struct btree_path *r)
56{
57 return __btree_path_cmp(l, r->btree_id, r->cached, r->pos, r->level);
0423fb71
KO		 58}
59
e751c01a
KO		 60static inline struct bpos bkey_successor(struct btree_iter *iter, struct bpos p)
61{
e751c01a
KO		 62 /* Are we iterating over keys in all snapshots? */
63 if (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) {
64 p = bpos_successor(p);
65 } else {
66 p = bpos_nosnap_successor(p);
67 p.snapshot = iter->snapshot;
68 }
69
70 return p;
71}
72
73static inline struct bpos bkey_predecessor(struct btree_iter *iter, struct bpos p)
74{
e751c01a
KO		 75 /* Are we iterating over keys in all snapshots? */
76 if (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) {
77 p = bpos_predecessor(p);
78 } else {
79 p = bpos_nosnap_predecessor(p);
80 p.snapshot = iter->snapshot;
81 }
82
83 return p;
84}
85
9626aeb1 86static inline struct bpos btree_iter_search_key(struct btree_iter *iter)
a00fd8c5 87{
9626aeb1 88 struct bpos pos = iter->pos;
cbdf24ce 89
9626aeb1 90 if ((iter->flags & BTREE_ITER_IS_EXTENTS) &&
e88a75eb 91 !bkey_eq(pos, POS_MAX))
e751c01a 92 pos = bkey_successor(iter, pos);
9626aeb1 93 return pos;
a00fd8c5
KO		 94}
95
67e0dd8f 96static inline bool btree_path_pos_before_node(struct btree_path *path,
e3ecf4f5
KO		 97 struct btree *b)
98{
e88a75eb 99 return bpos_lt(path->pos, b->data->min_key);
e3ecf4f5
KO		 100}
101
67e0dd8f 102static inline bool btree_path_pos_after_node(struct btree_path *path,
e3ecf4f5
KO		 103 struct btree *b)
104{
e88a75eb 105 return bpos_gt(path->pos, b->key.k.p);
e3ecf4f5
KO		 106}
107
67e0dd8f 108static inline bool btree_path_pos_in_node(struct btree_path *path,
e3ecf4f5
KO		 109 struct btree *b)
110{
67e0dd8f
KO		 111 return path->btree_id == b->c.btree_id &&
112 !btree_path_pos_before_node(path, b) &&
113 !btree_path_pos_after_node(path, b);
e3ecf4f5
KO		 114}
115
1c6fdbd8
KO		 116/* Btree iterator: */
117
118#ifdef CONFIG_BCACHEFS_DEBUG
119
67e0dd8f
KO		 120static void bch2_btree_path_verify_cached(struct btree_trans *trans,
121 struct btree_path *path)
d211b408
KO		 122{
123 struct bkey_cached *ck;
67e0dd8f 124 bool locked = btree_node_locked(path, 0);
d211b408 125
67e0dd8f 126 if (!bch2_btree_node_relock(trans, path, 0))
d211b408
KO		 127 return;
128
67e0dd8f
KO		 129 ck = (void *) path->l[0].b;
130 BUG_ON(ck->key.btree_id != path->btree_id ||
e88a75eb 131 !bkey_eq(ck->key.pos, path->pos));
d211b408
KO		 132
133 if (!locked)
8bfe14e8 134 btree_node_unlock(trans, path, 0);
d211b408
KO		 135}
136
67e0dd8f
KO		 137static void bch2_btree_path_verify_level(struct btree_trans *trans,
138 struct btree_path *path, unsigned level)
1c6fdbd8 139{
67e0dd8f 140 struct btree_path_level *l;
4ce41957
KO		 141 struct btree_node_iter tmp;
142 bool locked;
2dac0eae 143 struct bkey_packed *p, *k;
fa8e94fa
KO		 144 struct printbuf buf1 = PRINTBUF;
145 struct printbuf buf2 = PRINTBUF;
146 struct printbuf buf3 = PRINTBUF;
2dac0eae 147 const char *msg;
1c6fdbd8 148
29364f34 149 if (!bch2_debug_check_iterators)
f13f5a8c
KO		 150 return;
151
67e0dd8f 152 l = &path->l[level];
4ce41957 153 tmp = l->iter;
67e0dd8f 154 locked = btree_node_locked(path, level);
4ce41957 155
67e0dd8f 156 if (path->cached) {
d211b408 157 if (!level)
67e0dd8f 158 bch2_btree_path_verify_cached(trans, path);
d211b408
KO		 159 return;
160 }
161
67e0dd8f 162 if (!btree_path_node(path, level))
2dac0eae
KO		 163 return;
164
e9174370 165 if (!bch2_btree_node_relock_notrace(trans, path, level))
271a3d3a
KO		 166 return;
167
67e0dd8f 168 BUG_ON(!btree_path_pos_in_node(path, l->b));
2dac0eae 169
2dac0eae 170 bch2_btree_node_iter_verify(&l->iter, l->b);
1c6fdbd8
KO		 171
172 /*
1ae29c1f 173 * For interior nodes, the iterator will have skipped past deleted keys:
1c6fdbd8 174 */
1ae29c1f 175 p = level
c052cf82 176 ? bch2_btree_node_iter_prev(&tmp, l->b)
2dac0eae
KO		 177 : bch2_btree_node_iter_prev_all(&tmp, l->b);
178 k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
1c6fdbd8 179
67e0dd8f 180 if (p && bkey_iter_pos_cmp(l->b, p, &path->pos) >= 0) {
2dac0eae
KO		 181 msg = "before";
182 goto err;
1c6fdbd8
KO		 183 }
184
67e0dd8f 185 if (k && bkey_iter_pos_cmp(l->b, k, &path->pos) < 0) {
2dac0eae
KO		 186 msg = "after";
187 goto err;
188 }
f21566f1 189
2dac0eae 190 if (!locked)
8bfe14e8 191 btree_node_unlock(trans, path, level);
2dac0eae
KO		 192 return;
193err:
fa8e94fa 194 bch2_bpos_to_text(&buf1, path->pos);
2dac0eae
KO		 195
196 if (p) {
197 struct bkey uk = bkey_unpack_key(l->b, p);
a1019576 198
fa8e94fa
KO		 199 bch2_bkey_to_text(&buf2, &uk);
200 } else {
401ec4db 201 prt_printf(&buf2, "(none)");
2dac0eae 202 }
1c6fdbd8 203
2dac0eae
KO		 204 if (k) {
205 struct bkey uk = bkey_unpack_key(l->b, k);
a1019576 206
fa8e94fa
KO		 207 bch2_bkey_to_text(&buf3, &uk);
208 } else {
401ec4db 209 prt_printf(&buf3, "(none)");
1c6fdbd8 210 }
2dac0eae 211
67e0dd8f
KO		 212 panic("path should be %s key at level %u:\n"
213 "path pos %s\n"
2dac0eae
KO		 214 "prev key %s\n"
215 "cur key %s\n",
fa8e94fa 216 msg, level, buf1.buf, buf2.buf, buf3.buf);
1c6fdbd8
KO		 217}
218
67e0dd8f
KO		 219static void bch2_btree_path_verify(struct btree_trans *trans,
220 struct btree_path *path)
1c6fdbd8 221{
5aab6635 222 struct bch_fs *c = trans->c;
2dac0eae 223 unsigned i;
1c6fdbd8 224
67e0dd8f
KO		 225 EBUG_ON(path->btree_id >= BTREE_ID_NR);
226
227 for (i = 0; i < (!path->cached ? BTREE_MAX_DEPTH : 1); i++) {
228 if (!path->l[i].b) {
d7407292 229 BUG_ON(!path->cached &&
faa6cb6c 230 bch2_btree_id_root(c, path->btree_id)->b->c.level > i);
67e0dd8f
KO		 231 break;
232 }
233
234 bch2_btree_path_verify_level(trans, path, i);
235 }
236
237 bch2_btree_path_verify_locks(path);
238}
239
240void bch2_trans_verify_paths(struct btree_trans *trans)
241{
242 struct btree_path *path;
243
67e0dd8f
KO		 244 trans_for_each_path(trans, path)
245 bch2_btree_path_verify(trans, path);
246}
247
248static void bch2_btree_iter_verify(struct btree_iter *iter)
249{
250 struct btree_trans *trans = iter->trans;
251
252 BUG_ON(iter->btree_id >= BTREE_ID_NR);
253
254 BUG_ON(!!(iter->flags & BTREE_ITER_CACHED) != iter->path->cached);
7e1a3aa9 255
e751c01a
KO		 256 BUG_ON((iter->flags & BTREE_ITER_IS_EXTENTS) &&
257 (iter->flags & BTREE_ITER_ALL_SNAPSHOTS));
258
f21566f1 259 BUG_ON(!(iter->flags & __BTREE_ITER_ALL_SNAPSHOTS) &&
e751c01a 260 (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) &&
9fcdd23b 261 !btree_type_has_snapshot_field(iter->btree_id));
e751c01a 262
1f2d9192
KO		 263 if (iter->update_path)
264 bch2_btree_path_verify(trans, iter->update_path);
67e0dd8f 265 bch2_btree_path_verify(trans, iter->path);
2dac0eae
KO		 266}
267
7e1a3aa9
KO		 268static void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter)
269{
a861c722
KO		 270 BUG_ON((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) &&
271 !iter->pos.snapshot);
272
e751c01a
KO		 273 BUG_ON(!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS) &&
274 iter->pos.snapshot != iter->snapshot);
275
e88a75eb
KO		 276 BUG_ON(bkey_lt(iter->pos, bkey_start_pos(&iter->k)) ||
277 bkey_gt(iter->pos, iter->k.p));
7e1a3aa9
KO		 278}
279
c075ff70
KO		 280static int bch2_btree_iter_verify_ret(struct btree_iter *iter, struct bkey_s_c k)
281{
282 struct btree_trans *trans = iter->trans;
283 struct btree_iter copy;
284 struct bkey_s_c prev;
285 int ret = 0;
286
287 if (!bch2_debug_check_iterators)
288 return 0;
289
290 if (!(iter->flags & BTREE_ITER_FILTER_SNAPSHOTS))
291 return 0;
292
293 if (bkey_err(k) || !k.k)
294 return 0;
295
296 BUG_ON(!bch2_snapshot_is_ancestor(trans->c,
297 iter->snapshot,
298 k.k->p.snapshot));
299
300 bch2_trans_iter_init(trans, &copy, iter->btree_id, iter->pos,
ffa7d262 301 BTREE_ITER_NOPRESERVE|
c075ff70
KO		 302 BTREE_ITER_ALL_SNAPSHOTS);
303 prev = bch2_btree_iter_prev(&copy);
304 if (!prev.k)
305 goto out;
306
307 ret = bkey_err(prev);
308 if (ret)
309 goto out;
310
e88a75eb 311 if (bkey_eq(prev.k->p, k.k->p) &&
c075ff70
KO		 312 bch2_snapshot_is_ancestor(trans->c, iter->snapshot,
313 prev.k->p.snapshot) > 0) {
fa8e94fa 314 struct printbuf buf1 = PRINTBUF, buf2 = PRINTBUF;
c075ff70 315
fa8e94fa
KO		 316 bch2_bkey_to_text(&buf1, k.k);
317 bch2_bkey_to_text(&buf2, prev.k);
c075ff70
KO		 318
319 panic("iter snap %u\n"
320 "k %s\n"
321 "prev %s\n",
322 iter->snapshot,
fa8e94fa 323 buf1.buf, buf2.buf);
c075ff70
KO		 324 }
325out:
326 bch2_trans_iter_exit(trans, &copy);
327 return ret;
328}
329
32b26e8c
KO		 330void bch2_assert_pos_locked(struct btree_trans *trans, enum btree_id id,
331 struct bpos pos, bool key_cache)
332{
333 struct btree_path *path;
334 unsigned idx;
fa8e94fa 335 struct printbuf buf = PRINTBUF;
32b26e8c 336
5c0bb66a
KO		 337 btree_trans_sort_paths(trans);
338
32b26e8c
KO		 339 trans_for_each_path_inorder(trans, path, idx) {
340 int cmp = cmp_int(path->btree_id, id) ?:
341 cmp_int(path->cached, key_cache);
342
343 if (cmp > 0)
344 break;
345 if (cmp < 0)
346 continue;
347
d4263e56 348 if (!btree_node_locked(path, 0) ||
32b26e8c
KO		 349 !path->should_be_locked)
350 continue;
351
352 if (!key_cache) {
e88a75eb
KO		 353 if (bkey_ge(pos, path->l[0].b->data->min_key) &&
354 bkey_le(pos, path->l[0].b->key.k.p))
32b26e8c
KO		 355 return;
356 } else {
e88a75eb 357 if (bkey_eq(pos, path->pos))
32b26e8c
KO		 358 return;
359 }
360 }
361
362 bch2_dump_trans_paths_updates(trans);
fa8e94fa
KO		 363 bch2_bpos_to_text(&buf, pos);
364
32b26e8c 365 panic("not locked: %s %s%s\n",
88dfe193 366 bch2_btree_id_str(id), buf.buf,
32b26e8c
KO		 367 key_cache ? " cached" : "");
368}
369
271a3d3a
KO		 370#else
371
67e0dd8f
KO		 372static inline void bch2_btree_path_verify_level(struct btree_trans *trans,
373 struct btree_path *path, unsigned l) {}
374static inline void bch2_btree_path_verify(struct btree_trans *trans,
375 struct btree_path *path) {}
7d6f9b64 376static inline void bch2_btree_iter_verify(struct btree_iter *iter) {}
7e1a3aa9 377static inline void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter) {}
c075ff70 378static inline int bch2_btree_iter_verify_ret(struct btree_iter *iter, struct bkey_s_c k) { return 0; }
271a3d3a 379
1c6fdbd8
KO		 380#endif
381
67e0dd8f
KO		 382/* Btree path: fixups after btree updates */
383
23bbd2bb
KO		 384static void btree_node_iter_set_set_pos(struct btree_node_iter *iter,
385 struct btree *b,
386 struct bset_tree *t,
387 struct bkey_packed *k)
388{
389 struct btree_node_iter_set *set;
390
391 btree_node_iter_for_each(iter, set)
392 if (set->end == t->end_offset) {
393 set->k = __btree_node_key_to_offset(b, k);
394 bch2_btree_node_iter_sort(iter, b);
395 return;
396 }
397
398 bch2_btree_node_iter_push(iter, b, k, btree_bkey_last(b, t));
399}
400
67e0dd8f 401static void __bch2_btree_path_fix_key_modified(struct btree_path *path,
9626aeb1
KO		 402 struct btree *b,
403 struct bkey_packed *where)
887c2a4e 404{
67e0dd8f 405 struct btree_path_level *l = &path->l[b->c.level];
887c2a4e 406
9626aeb1
KO		 407 if (where != bch2_btree_node_iter_peek_all(&l->iter, l->b))
408 return;
409
67e0dd8f 410 if (bkey_iter_pos_cmp(l->b, where, &path->pos) < 0)
9626aeb1 411 bch2_btree_node_iter_advance(&l->iter, l->b);
887c2a4e
KO		 412}
413
67e0dd8f 414void bch2_btree_path_fix_key_modified(struct btree_trans *trans,
887c2a4e
KO		 415 struct btree *b,
416 struct bkey_packed *where)
417{
67e0dd8f 418 struct btree_path *path;
887c2a4e 419
67e0dd8f
KO		 420 trans_for_each_path_with_node(trans, b, path) {
421 __bch2_btree_path_fix_key_modified(path, b, where);
422 bch2_btree_path_verify_level(trans, path, b->c.level);
887c2a4e
KO		 423 }
424}
425
67e0dd8f
KO		 426static void __bch2_btree_node_iter_fix(struct btree_path *path,
427 struct btree *b,
428 struct btree_node_iter *node_iter,
429 struct bset_tree *t,
430 struct bkey_packed *where,
431 unsigned clobber_u64s,
432 unsigned new_u64s)
1c6fdbd8
KO		 433{
434 const struct bkey_packed *end = btree_bkey_last(b, t);
435 struct btree_node_iter_set *set;
436 unsigned offset = __btree_node_key_to_offset(b, where);
437 int shift = new_u64s - clobber_u64s;
271a3d3a 438 unsigned old_end = t->end_offset - shift;
c0fc30da
KO		 439 unsigned orig_iter_pos = node_iter->data[0].k;
440 bool iter_current_key_modified =
441 orig_iter_pos >= offset &&
442 orig_iter_pos <= offset + clobber_u64s;
1c6fdbd8
KO		 443
444 btree_node_iter_for_each(node_iter, set)
445 if (set->end == old_end)
446 goto found;
447
448 /* didn't find the bset in the iterator - might have to readd it: */
449 if (new_u64s &&
67e0dd8f 450 bkey_iter_pos_cmp(b, where, &path->pos) >= 0) {
1c6fdbd8 451 bch2_btree_node_iter_push(node_iter, b, where, end);
c0fc30da
KO		 452 goto fixup_done;
453 } else {
454 /* Iterator is after key that changed */
059e4134 455 return;
1c6fdbd8 456 }
1c6fdbd8 457found:
271a3d3a 458 set->end = t->end_offset;
1c6fdbd8
KO		 459
460 /* Iterator hasn't gotten to the key that changed yet: */
461 if (set->k < offset)
059e4134 462 return;
1c6fdbd8
KO		 463
464 if (new_u64s &&
67e0dd8f 465 bkey_iter_pos_cmp(b, where, &path->pos) >= 0) {
1c6fdbd8
KO		 466 set->k = offset;
467 } else if (set->k < offset + clobber_u64s) {
468 set->k = offset + new_u64s;
469 if (set->k == set->end)
470 bch2_btree_node_iter_set_drop(node_iter, set);
471 } else {
c0fc30da 472 /* Iterator is after key that changed */
1c6fdbd8 473 set->k = (int) set->k + shift;
059e4134 474 return;
1c6fdbd8
KO		 475 }
476
1c6fdbd8 477 bch2_btree_node_iter_sort(node_iter, b);
c0fc30da
KO		 478fixup_done:
479 if (node_iter->data[0].k != orig_iter_pos)
480 iter_current_key_modified = true;
56e0e7c7 481
1c6fdbd8 482 /*
23bbd2bb
KO		 483 * When a new key is added, and the node iterator now points to that
484 * key, the iterator might have skipped past deleted keys that should
485 * come after the key the iterator now points to. We have to rewind to
c0fc30da
KO		 486 * before those deleted keys - otherwise
487 * bch2_btree_node_iter_prev_all() breaks:
1c6fdbd8 488 */
23bbd2bb 489 if (!bch2_btree_node_iter_end(node_iter) &&
c0fc30da 490 iter_current_key_modified &&
1ae29c1f 491 b->c.level) {
23bbd2bb
KO		 492 struct bkey_packed *k, *k2, *p;
493
494 k = bch2_btree_node_iter_peek_all(node_iter, b);
1c6fdbd8
KO		 495
496 for_each_bset(b, t) {
23bbd2bb
KO		 497 bool set_pos = false;
498
499 if (node_iter->data[0].end == t->end_offset)
1c6fdbd8
KO		 500 continue;
501
23bbd2bb
KO		 502 k2 = bch2_btree_node_iter_bset_pos(node_iter, b, t);
503
504 while ((p = bch2_bkey_prev_all(b, t, k2)) &&
505 bkey_iter_cmp(b, k, p) < 0) {
506 k2 = p;
507 set_pos = true;
1c6fdbd8 508 }
23bbd2bb
KO		 509
510 if (set_pos)
511 btree_node_iter_set_set_pos(node_iter,
512 b, t, k2);
1c6fdbd8
KO		 513 }
514 }
515}
516
9f6bd307 517void bch2_btree_node_iter_fix(struct btree_trans *trans,
67e0dd8f 518 struct btree_path *path,
216c9fac
KO		 519 struct btree *b,
520 struct btree_node_iter *node_iter,
521 struct bkey_packed *where,
522 unsigned clobber_u64s,
523 unsigned new_u64s)
1c6fdbd8 524{
216c9fac 525 struct bset_tree *t = bch2_bkey_to_bset_inlined(b, where);
67e0dd8f 526 struct btree_path *linked;
1c6fdbd8 527
67e0dd8f
KO		 528 if (node_iter != &path->l[b->c.level].iter) {
529 __bch2_btree_node_iter_fix(path, b, node_iter, t,
059e4134 530 where, clobber_u64s, new_u64s);
2dac0eae 531
29364f34 532 if (bch2_debug_check_iterators)
2dac0eae 533 bch2_btree_node_iter_verify(node_iter, b);
059e4134 534 }
1c6fdbd8 535
67e0dd8f 536 trans_for_each_path_with_node(trans, b, linked) {
1c6fdbd8 537 __bch2_btree_node_iter_fix(linked, b,
059e4134
KO		 538 &linked->l[b->c.level].iter, t,
539 where, clobber_u64s, new_u64s);
67e0dd8f 540 bch2_btree_path_verify_level(trans, linked, b->c.level);
059e4134 541 }
1c6fdbd8
KO		 542}
543
67e0dd8f
KO		 544/* Btree path level: pointer to a particular btree node and node iter */
545
546static inline struct bkey_s_c __btree_iter_unpack(struct bch_fs *c,
547 struct btree_path_level *l,
1c6fdbd8
KO		 548 struct bkey *u,
549 struct bkey_packed *k)
550{
1c6fdbd8
KO		 551 if (unlikely(!k)) {
552 /*
553 * signal to bch2_btree_iter_peek_slot() that we're currently at
554 * a hole
555 */
26609b61 556 u->type = KEY_TYPE_deleted;
1c6fdbd8
KO		 557 return bkey_s_c_null;
558 }
559
2ce8fbd9 560 return bkey_disassemble(l->b, k, u);
1c6fdbd8
KO		 561}
562
67e0dd8f
KO		 563static inline struct bkey_s_c btree_path_level_peek_all(struct bch_fs *c,
564 struct btree_path_level *l,
565 struct bkey *u)
1c6fdbd8 566{
67e0dd8f 567 return __btree_iter_unpack(c, l, u,
1c6fdbd8
KO		 568 bch2_btree_node_iter_peek_all(&l->iter, l->b));
569}
570
67e0dd8f
KO		 571static inline struct bkey_s_c btree_path_level_peek(struct btree_trans *trans,
572 struct btree_path *path,
573 struct btree_path_level *l,
574 struct bkey *u)
1c6fdbd8 575{
67e0dd8f 576 struct bkey_s_c k = __btree_iter_unpack(trans->c, l, u,
1c6fdbd8 577 bch2_btree_node_iter_peek(&l->iter, l->b));
ca58cbd4 578
67e0dd8f
KO		 579 path->pos = k.k ? k.k->p : l->b->key.k.p;
580 trans->paths_sorted = false;
01eed771 581 bch2_btree_path_verify_level(trans, path, l - path->l);
ca58cbd4 582 return k;
1c6fdbd8
KO		 583}
584
67e0dd8f
KO		 585static inline struct bkey_s_c btree_path_level_prev(struct btree_trans *trans,
586 struct btree_path *path,
587 struct btree_path_level *l,
588 struct bkey *u)
ccf5a109 589{
67e0dd8f 590 struct bkey_s_c k = __btree_iter_unpack(trans->c, l, u,
ccf5a109 591 bch2_btree_node_iter_prev(&l->iter, l->b));
ca58cbd4 592
67e0dd8f
KO		 593 path->pos = k.k ? k.k->p : l->b->data->min_key;
594 trans->paths_sorted = false;
01eed771 595 bch2_btree_path_verify_level(trans, path, l - path->l);
ca58cbd4 596 return k;
ccf5a109
KO		 597}
598
67e0dd8f
KO		 599static inline bool btree_path_advance_to_pos(struct btree_path *path,
600 struct btree_path_level *l,
a00fd8c5 601 int max_advance)
1c6fdbd8 602{
a00fd8c5
KO		 603 struct bkey_packed *k;
604 int nr_advanced = 0;
605
606 while ((k = bch2_btree_node_iter_peek_all(&l->iter, l->b)) &&
67e0dd8f 607 bkey_iter_pos_cmp(l->b, k, &path->pos) < 0) {
a00fd8c5
KO		 608 if (max_advance > 0 && nr_advanced >= max_advance)
609 return false;
610
611 bch2_btree_node_iter_advance(&l->iter, l->b);
612 nr_advanced++;
613 }
614
615 return true;
1c6fdbd8
KO		 616}
617
67e0dd8f 618static inline void __btree_path_level_init(struct btree_path *path,
78cf784e 619 unsigned level)
1c6fdbd8 620{
67e0dd8f 621 struct btree_path_level *l = &path->l[level];
a00fd8c5 622
67e0dd8f 623 bch2_btree_node_iter_init(&l->iter, l->b, &path->pos);
1c6fdbd8 624
537c49d6
KO		 625 /*
626 * Iterators to interior nodes should always be pointed at the first non
627 * whiteout:
628 */
629 if (level)
630 bch2_btree_node_iter_peek(&l->iter, l->b);
1c6fdbd8
KO		 631}
632
b2d1d56b
KO		 633void bch2_btree_path_level_init(struct btree_trans *trans,
634 struct btree_path *path,
635 struct btree *b)
1c6fdbd8 636{
67e0dd8f 637 BUG_ON(path->cached);
2ca88e5a 638
67e0dd8f 639 EBUG_ON(!btree_path_pos_in_node(path, b));
1c6fdbd8 640
1fb4fe63 641 path->l[b->c.level].lock_seq = six_lock_seq(&b->c.lock);
67e0dd8f
KO		 642 path->l[b->c.level].b = b;
643 __btree_path_level_init(path, b->c.level);
1c6fdbd8
KO		 644}
645
67e0dd8f
KO		 646/* Btree path: fixups after btree node updates: */
647
08f78031
KO		 648static void bch2_trans_revalidate_updates_in_node(struct btree_trans *trans, struct btree *b)
649{
650 struct bch_fs *c = trans->c;
651 struct btree_insert_entry *i;
652
653 trans_for_each_update(trans, i)
654 if (!i->cached &&
655 i->level == b->c.level &&
656 i->btree_id == b->c.btree_id &&
657 bpos_cmp(i->k->k.p, b->data->min_key) >= 0 &&
658 bpos_cmp(i->k->k.p, b->data->max_key) <= 0) {
659 i->old_v = bch2_btree_path_peek_slot(i->path, &i->old_k).v;
660
661 if (unlikely(trans->journal_replay_not_finished)) {
662 struct bkey_i *j_k =
663 bch2_journal_keys_peek_slot(c, i->btree_id, i->level,
664 i->k->k.p);
665
666 if (j_k) {
667 i->old_k = j_k->k;
668 i->old_v = &j_k->v;
669 }
670 }
671 }
672}
673
1c6fdbd8
KO		 674/*
675 * A btree node is being replaced - update the iterator to point to the new
676 * node:
677 */
f3360005
KO		 678void bch2_trans_node_add(struct btree_trans *trans,
679 struct btree_path *path,
680 struct btree *b)
1c6fdbd8 681{
f3360005 682 struct btree_path *prev;
1c6fdbd8 683
f3360005
KO		 684 BUG_ON(!btree_path_pos_in_node(path, b));
685
686 while ((prev = prev_btree_path(trans, path)) &&
687 btree_path_pos_in_node(prev, b))
688 path = prev;
689
690 for (;
691 path && btree_path_pos_in_node(path, b);
692 path = next_btree_path(trans, path))
693 if (path->uptodate == BTREE_ITER_UPTODATE && !path->cached) {
1d3ecd7e
KO		 694 enum btree_node_locked_type t =
695 btree_lock_want(path, b->c.level);
1c6fdbd8 696
38474c26 697 if (t != BTREE_NODE_UNLOCKED) {
8bfe14e8 698 btree_node_unlock(trans, path, b->c.level);
c43a6ef9 699 six_lock_increment(&b->c.lock, (enum six_lock_type) t);
5b7fbdcd 700 mark_btree_node_locked(trans, path, b->c.level, t);
1c6fdbd8
KO		 701 }
702
e4215d0f 703 bch2_btree_path_level_init(trans, path, b);
1c6fdbd8 704 }
08f78031
KO		 705
706 bch2_trans_revalidate_updates_in_node(trans, b);
1c6fdbd8
KO		 707}
708
1c6fdbd8
KO		 709/*
710 * A btree node has been modified in such a way as to invalidate iterators - fix
711 * them:
712 */
f7a966a3 713void bch2_trans_node_reinit_iter(struct btree_trans *trans, struct btree *b)
1c6fdbd8 714{
67e0dd8f 715 struct btree_path *path;
1c6fdbd8 716
67e0dd8f
KO		 717 trans_for_each_path_with_node(trans, b, path)
718 __btree_path_level_init(path, b->c.level);
08f78031
KO		 719
720 bch2_trans_revalidate_updates_in_node(trans, b);
1c6fdbd8
KO		 721}
722
67e0dd8f
KO		 723/* Btree path: traverse, set_pos: */
724
67e0dd8f
KO		 725static inline int btree_path_lock_root(struct btree_trans *trans,
726 struct btree_path *path,
a301dc38
KO		 727 unsigned depth_want,
728 unsigned long trace_ip)
1c6fdbd8 729{
e5af273f 730 struct bch_fs *c = trans->c;
faa6cb6c 731 struct btree *b, **rootp = &bch2_btree_id_root(c, path->btree_id)->b;
1c6fdbd8
KO		 732 enum six_lock_type lock_type;
733 unsigned i;
549d173c 734 int ret;
1c6fdbd8 735
67e0dd8f 736 EBUG_ON(path->nodes_locked);
1c6fdbd8
KO		 737
738 while (1) {
bd2bb273 739 b = READ_ONCE(*rootp);
67e0dd8f 740 path->level = READ_ONCE(b->c.level);
1c6fdbd8 741
67e0dd8f 742 if (unlikely(path->level < depth_want)) {
1c6fdbd8
KO		 743 /*
744 * the root is at a lower depth than the depth we want:
745 * got to the end of the btree, or we're walking nodes
746 * greater than some depth and there are no nodes >=
747 * that depth
748 */
67e0dd8f
KO		 749 path->level = depth_want;
750 for (i = path->level; i < BTREE_MAX_DEPTH; i++)
751 path->l[i].b = NULL;
8812600c 752 return 1;
1c6fdbd8
KO		 753 }
754
67e0dd8f 755 lock_type = __btree_lock_want(path, path->level);
0d7009d7
KO		 756 ret = btree_node_lock(trans, path, &b->c,
757 path->level, lock_type, trace_ip);
549d173c
KO		 758 if (unlikely(ret)) {
759 if (bch2_err_matches(ret, BCH_ERR_lock_fail_root_changed))
760 continue;
761 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
762 return ret;
763 BUG();
e5af273f 764 }
1c6fdbd8 765
bd2bb273 766 if (likely(b == READ_ONCE(*rootp) &&
67e0dd8f 767 b->c.level == path->level &&
1c6fdbd8 768 !race_fault())) {
67e0dd8f 769 for (i = 0; i < path->level; i++)
315c9ba6 770 path->l[i].b = ERR_PTR(-BCH_ERR_no_btree_node_lock_root);
67e0dd8f
KO		 771 path->l[path->level].b = b;
772 for (i = path->level + 1; i < BTREE_MAX_DEPTH; i++)
773 path->l[i].b = NULL;
774
5b7fbdcd
KO		 775 mark_btree_node_locked(trans, path, path->level,
776 (enum btree_node_locked_type) lock_type);
e4215d0f 777 bch2_btree_path_level_init(trans, path, b);
1c6fdbd8 778 return 0;
1c6fdbd8
KO		 779 }
780
c43a6ef9 781 six_unlock_type(&b->c.lock, lock_type);
1c6fdbd8
KO		 782 }
783}
784
785noinline
67e0dd8f 786static int btree_path_prefetch(struct btree_trans *trans, struct btree_path *path)
1c6fdbd8 787{
9f6bd307 788 struct bch_fs *c = trans->c;
67e0dd8f 789 struct btree_path_level *l = path_l(path);
1c6fdbd8
KO		 790 struct btree_node_iter node_iter = l->iter;
791 struct bkey_packed *k;
07a1006a 792 struct bkey_buf tmp;
3c471b65 793 unsigned nr = test_bit(BCH_FS_started, &c->flags)
67e0dd8f
KO		 794 ? (path->level > 1 ? 0 : 2)
795 : (path->level > 1 ? 1 : 16);
796 bool was_locked = btree_node_locked(path, path->level);
8b3e9bd6 797 int ret = 0;
1c6fdbd8 798
07a1006a
KO		 799 bch2_bkey_buf_init(&tmp);
800
dccedaaa 801 while (nr-- && !ret) {
67e0dd8f 802 if (!bch2_btree_node_relock(trans, path, path->level))
07a1006a 803 break;
1c6fdbd8
KO		 804
805 bch2_btree_node_iter_advance(&node_iter, l->b);
806 k = bch2_btree_node_iter_peek(&node_iter, l->b);
807 if (!k)
808 break;
809
07a1006a 810 bch2_bkey_buf_unpack(&tmp, c, l->b, k);
1306f87d 811 ret = bch2_btree_node_prefetch(trans, path, tmp.k, path->btree_id,
67e0dd8f 812 path->level - 1);
1c6fdbd8
KO		 813 }
814
815 if (!was_locked)
8bfe14e8 816 btree_node_unlock(trans, path, path->level);
07a1006a
KO		 817
818 bch2_bkey_buf_exit(&tmp, c);
8b3e9bd6 819 return ret;
1c6fdbd8
KO		 820}
821
5222a460
KO		 822static int btree_path_prefetch_j(struct btree_trans *trans, struct btree_path *path,
823 struct btree_and_journal_iter *jiter)
824{
825 struct bch_fs *c = trans->c;
826 struct bkey_s_c k;
827 struct bkey_buf tmp;
3c471b65 828 unsigned nr = test_bit(BCH_FS_started, &c->flags)
5222a460
KO		 829 ? (path->level > 1 ? 0 : 2)
830 : (path->level > 1 ? 1 : 16);
831 bool was_locked = btree_node_locked(path, path->level);
832 int ret = 0;
833
834 bch2_bkey_buf_init(&tmp);
835
dccedaaa 836 while (nr-- && !ret) {
5222a460
KO		 837 if (!bch2_btree_node_relock(trans, path, path->level))
838 break;
839
840 bch2_btree_and_journal_iter_advance(jiter);
841 k = bch2_btree_and_journal_iter_peek(jiter);
842 if (!k.k)
843 break;
844
845 bch2_bkey_buf_reassemble(&tmp, c, k);
1306f87d 846 ret = bch2_btree_node_prefetch(trans, path, tmp.k, path->btree_id,
5222a460
KO		 847 path->level - 1);
848 }
849
850 if (!was_locked)
8bfe14e8 851 btree_node_unlock(trans, path, path->level);
5222a460
KO		 852
853 bch2_bkey_buf_exit(&tmp, c);
854 return ret;
855}
856
78cf784e 857static noinline void btree_node_mem_ptr_set(struct btree_trans *trans,
67e0dd8f 858 struct btree_path *path,
72141e1f
KO		 859 unsigned plevel, struct btree *b)
860{
67e0dd8f
KO		 861 struct btree_path_level *l = &path->l[plevel];
862 bool locked = btree_node_locked(path, plevel);
72141e1f
KO		 863 struct bkey_packed *k;
864 struct bch_btree_ptr_v2 *bp;
865
67e0dd8f 866 if (!bch2_btree_node_relock(trans, path, plevel))
72141e1f
KO		 867 return;
868
869 k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
870 BUG_ON(k->type != KEY_TYPE_btree_ptr_v2);
871
872 bp = (void *) bkeyp_val(&l->b->format, k);
873 bp->mem_ptr = (unsigned long)b;
874
875 if (!locked)
8bfe14e8 876 btree_node_unlock(trans, path, plevel);
72141e1f
KO		 877}
878
5222a460
KO		 879static noinline int btree_node_iter_and_journal_peek(struct btree_trans *trans,
880 struct btree_path *path,
881 unsigned flags,
882 struct bkey_buf *out)
883{
884 struct bch_fs *c = trans->c;
885 struct btree_path_level *l = path_l(path);
886 struct btree_and_journal_iter jiter;
887 struct bkey_s_c k;
888 int ret = 0;
889
890 __bch2_btree_and_journal_iter_init_node_iter(&jiter, c, l->b, l->iter, path->pos);
891
892 k = bch2_btree_and_journal_iter_peek(&jiter);
893
894 bch2_bkey_buf_reassemble(out, c, k);
895
896 if (flags & BTREE_ITER_PREFETCH)
897 ret = btree_path_prefetch_j(trans, path, &jiter);
898
899 bch2_btree_and_journal_iter_exit(&jiter);
900 return ret;
901}
902
67e0dd8f
KO		 903static __always_inline int btree_path_down(struct btree_trans *trans,
904 struct btree_path *path,
905 unsigned flags,
a301dc38 906 unsigned long trace_ip)
1c6fdbd8 907{
6e075b54 908 struct bch_fs *c = trans->c;
67e0dd8f 909 struct btree_path_level *l = path_l(path);
1c6fdbd8 910 struct btree *b;
67e0dd8f
KO		 911 unsigned level = path->level - 1;
912 enum six_lock_type lock_type = __btree_lock_want(path, level);
07a1006a
KO		 913 struct bkey_buf tmp;
914 int ret;
1c6fdbd8 915
67e0dd8f 916 EBUG_ON(!btree_node_locked(path, path->level));
1c6fdbd8 917
07a1006a 918 bch2_bkey_buf_init(&tmp);
5222a460
KO		 919
920 if (unlikely(trans->journal_replay_not_finished)) {
921 ret = btree_node_iter_and_journal_peek(trans, path, flags, &tmp);
922 if (ret)
923 goto err;
924 } else {
925 bch2_bkey_buf_unpack(&tmp, c, l->b,
926 bch2_btree_node_iter_peek(&l->iter, l->b));
927
928 if (flags & BTREE_ITER_PREFETCH) {
929 ret = btree_path_prefetch(trans, path);
930 if (ret)
931 goto err;
932 }
933 }
1c6fdbd8 934
67e0dd8f 935 b = bch2_btree_node_get(trans, path, tmp.k, level, lock_type, trace_ip);
07a1006a
KO		 936 ret = PTR_ERR_OR_ZERO(b);
937 if (unlikely(ret))
938 goto err;
1c6fdbd8 939
5222a460
KO		 940 if (likely(!trans->journal_replay_not_finished &&
941 tmp.k->k.type == KEY_TYPE_btree_ptr_v2) &&
07a1006a 942 unlikely(b != btree_node_mem_ptr(tmp.k)))
67e0dd8f 943 btree_node_mem_ptr_set(trans, path, level + 1, b);
72141e1f 944
67e0dd8f 945 if (btree_node_read_locked(path, level + 1))
8bfe14e8 946 btree_node_unlock(trans, path, level + 1);
223b560e 947
5b7fbdcd
KO		 948 mark_btree_node_locked(trans, path, level,
949 (enum btree_node_locked_type) lock_type);
67e0dd8f 950 path->level = level;
e4215d0f 951 bch2_btree_path_level_init(trans, path, b);
c205321b 952
67e0dd8f 953 bch2_btree_path_verify_locks(path);
07a1006a
KO		 954err:
955 bch2_bkey_buf_exit(&tmp, c);
956 return ret;
1c6fdbd8
KO		 957}
958
1c6fdbd8 959
8f9ad91a 960static int bch2_btree_path_traverse_all(struct btree_trans *trans)
1c6fdbd8 961{
e542029e 962 struct bch_fs *c = trans->c;
0d7009d7 963 struct btree_path *path;
8f9ad91a
KO		 964 unsigned long trace_ip = _RET_IP_;
965 int i, ret = 0;
e542029e 966
2ca88e5a 967 if (trans->in_traverse_all)
549d173c 968 return -BCH_ERR_transaction_restart_in_traverse_all;
2ca88e5a
KO		 969
970 trans->in_traverse_all = true;
971retry_all:
549d173c 972 trans->restarted = 0;
5e2d8be8 973 trans->last_restarted_ip = 0;
e5af273f 974
67e0dd8f
KO		 975 trans_for_each_path(trans, path)
976 path->should_be_locked = false;
e542029e 977
67e0dd8f 978 btree_trans_sort_paths(trans);
2527dd91 979
58fbf808 980 bch2_trans_unlock(trans);
a301dc38 981 cond_resched();
1c6fdbd8 982
8f9ad91a 983 if (unlikely(trans->memory_allocation_failure)) {
1c6fdbd8
KO		 984 struct closure cl;
985
986 closure_init_stack(&cl);
987
988 do {
a564c9fa 989 ret = bch2_btree_cache_cannibalize_lock(trans, &cl);
1c6fdbd8
KO		 990 closure_sync(&cl);
991 } while (ret);
992 }
993
1c6fdbd8 994 /* Now, redo traversals in correct order: */
0423fb71
KO		 995 i = 0;
996 while (i < trans->nr_sorted) {
67e0dd8f 997 path = trans->paths + trans->sorted[i];
2ca88e5a 998
33aa419d
KO		 999 /*
1000 * Traversing a path can cause another path to be added at about
1001 * the same position:
1002 */
1003 if (path->uptodate) {
c82ed304 1004 __btree_path_get(path, false);
4e3d1899 1005 ret = bch2_btree_path_traverse_one(trans, path, 0, _THIS_IP_);
c82ed304
KO		 1006 __btree_path_put(path, false);
1007
549d173c 1008 if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||
65d48e35 1009 bch2_err_matches(ret, ENOMEM))
33aa419d 1010 goto retry_all;
a897ef68
KO		 1011 if (ret)
1012 goto err;
33aa419d 1013 } else {
0423fb71 1014 i++;
33aa419d 1015 }
e542029e 1016 }
0423fb71
KO		 1017
1018 /*
ee94c413
KO		 1019 * We used to assert that all paths had been traversed here
1020 * (path->uptodate < BTREE_ITER_NEED_TRAVERSE); however, since
1e81f89b 1021 * path->should_be_locked is not set yet, we might have unlocked and
ee94c413 1022 * then failed to relock a path - that's fine.
0423fb71 1023 */
a897ef68 1024err:
a564c9fa 1025 bch2_btree_cache_cannibalize_unlock(trans);
2ca88e5a 1026
669f87a5
KO		 1027 trans->in_traverse_all = false;
1028
674cfc26 1029 trace_and_count(c, trans_traverse_all, trans, trace_ip);
1c6fdbd8 1030 return ret;
bf7b87a4 1031}
1c6fdbd8 1032
29aa78f1
KO		 1033static inline bool btree_path_check_pos_in_node(struct btree_path *path,
1034 unsigned l, int check_pos)
f4b61341 1035{
67e0dd8f 1036 if (check_pos < 0 && btree_path_pos_before_node(path, path->l[l].b))
f4b61341 1037 return false;
67e0dd8f 1038 if (check_pos > 0 && btree_path_pos_after_node(path, path->l[l].b))
f4b61341
KO		 1039 return false;
1040 return true;
1041}
1042
29aa78f1
KO		 1043static inline bool btree_path_good_node(struct btree_trans *trans,
1044 struct btree_path *path,
1045 unsigned l, int check_pos)
1046{
1047 return is_btree_node(path, l) &&
1048 bch2_btree_node_relock(trans, path, l) &&
1049 btree_path_check_pos_in_node(path, l, check_pos);
1050}
1051
c4bce586
KO		 1052static void btree_path_set_level_down(struct btree_trans *trans,
1053 struct btree_path *path,
1054 unsigned new_level)
1055{
1056 unsigned l;
1057
1058 path->level = new_level;
1059
1060 for (l = path->level + 1; l < BTREE_MAX_DEPTH; l++)
1061 if (btree_lock_want(path, l) == BTREE_NODE_UNLOCKED)
8bfe14e8 1062 btree_node_unlock(trans, path, l);
c4bce586
KO		 1063
1064 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
1065 bch2_btree_path_verify(trans, path);
1066}
1067
29aa78f1
KO		 1068static noinline unsigned __btree_path_up_until_good_node(struct btree_trans *trans,
1069 struct btree_path *path,
1070 int check_pos)
1c6fdbd8 1071{
8ee0134e 1072 unsigned i, l = path->level;
29cea6f4 1073again:
67e0dd8f 1074 while (btree_path_node(path, l) &&
315c9ba6
KO		 1075 !btree_path_good_node(trans, path, l, check_pos))
1076 __btree_path_set_level_up(trans, path, l++);
1c6fdbd8 1077
8ee0134e
KO		 1078 /* If we need intent locks, take them too: */
1079 for (i = l + 1;
1080 i < path->locks_want && btree_path_node(path, i);
1081 i++)
29cea6f4 1082 if (!bch2_btree_node_relock(trans, path, i)) {
315c9ba6
KO		 1083 while (l <= i)
1084 __btree_path_set_level_up(trans, path, l++);
29cea6f4
KO		 1085 goto again;
1086 }
8ee0134e 1087
1c6fdbd8
KO		 1088 return l;
1089}
1090
29aa78f1
KO		 1091static inline unsigned btree_path_up_until_good_node(struct btree_trans *trans,
1092 struct btree_path *path,
1093 int check_pos)
1094{
1095 return likely(btree_node_locked(path, path->level) &&
1096 btree_path_check_pos_in_node(path, path->level, check_pos))
1097 ? path->level
1098 : __btree_path_up_until_good_node(trans, path, check_pos);
1099}
1100
1c6fdbd8
KO		 1101/*
1102 * This is the main state machine for walking down the btree - walks down to a
1103 * specified depth
1104 *
1105 * Returns 0 on success, -EIO on error (error reading in a btree node).
1106 *
1107 * On error, caller (peek_node()/peek_key()) must return NULL; the error is
b7607ce9 1108 * stashed in the iterator and returned from bch2_trans_exit().
1c6fdbd8 1109 */
4e3d1899
KO		 1110int bch2_btree_path_traverse_one(struct btree_trans *trans,
1111 struct btree_path *path,
1112 unsigned flags,
1113 unsigned long trace_ip)
1c6fdbd8 1114{
8ee0134e 1115 unsigned depth_want = path->level;
0f35e086 1116 int ret = -((int) trans->restarted);
1c6fdbd8 1117
549d173c 1118 if (unlikely(ret))
979735df 1119 goto out;
979735df 1120
c4accde4
KO		 1121 if (unlikely(!trans->srcu_held))
1122 bch2_trans_srcu_lock(trans);
1123
e829b717 1124 /*
67e0dd8f
KO		 1125 * Ensure we obey path->should_be_locked: if it's set, we can't unlock
1126 * and re-traverse the path without a transaction restart:
e829b717 1127 */
67e0dd8f 1128 if (path->should_be_locked) {
549d173c 1129 ret = bch2_btree_path_relock(trans, path, trace_ip);
e829b717
KO		 1130 goto out;
1131 }
1132
67e0dd8f
KO		 1133 if (path->cached) {
1134 ret = bch2_btree_path_traverse_cached(trans, path, flags);
531a0095
KO		 1135 goto out;
1136 }
2ca88e5a 1137
67e0dd8f 1138 if (unlikely(path->level >= BTREE_MAX_DEPTH))
531a0095 1139 goto out;
2ca88e5a 1140
67e0dd8f 1141 path->level = btree_path_up_until_good_node(trans, path, 0);
1c6fdbd8 1142
845cffed
KO		 1143 EBUG_ON(btree_path_node(path, path->level) &&
1144 !btree_node_locked(path, path->level));
1145
1c6fdbd8 1146 /*
67e0dd8f 1147 * Note: path->nodes[path->level] may be temporarily NULL here - that
1c6fdbd8
KO		 1148 * would indicate to other code that we got to the end of the btree,
1149 * here it indicates that relocking the root failed - it's critical that
67e0dd8f 1150 * btree_path_lock_root() comes next and that it can't fail
1c6fdbd8 1151 */
67e0dd8f
KO		 1152 while (path->level > depth_want) {
1153 ret = btree_path_node(path, path->level)
1154 ? btree_path_down(trans, path, flags, trace_ip)
1155 : btree_path_lock_root(trans, path, depth_want, trace_ip);
1c6fdbd8 1156 if (unlikely(ret)) {
531a0095
KO		 1157 if (ret == 1) {
1158 /*
f21566f1
KO		 1159 * No nodes at this level - got to the end of
1160 * the btree:
531a0095
KO		 1161 */
1162 ret = 0;
1163 goto out;
1164 }
8812600c 1165
8bfe14e8 1166 __bch2_btree_path_unlock(trans, path);
67e0dd8f 1167 path->level = depth_want;
315c9ba6 1168 path->l[path->level].b = ERR_PTR(ret);
531a0095 1169 goto out;
1c6fdbd8
KO		 1170 }
1171 }
1172
67e0dd8f 1173 path->uptodate = BTREE_ITER_UPTODATE;
531a0095 1174out:
434b1c75
KO		 1175 if (bch2_err_matches(ret, BCH_ERR_transaction_restart) != !!trans->restarted)
1176 panic("ret %s (%i) trans->restarted %s (%i)\n",
1177 bch2_err_str(ret), ret,
1178 bch2_err_str(trans->restarted), trans->restarted);
67e0dd8f 1179 bch2_btree_path_verify(trans, path);
531a0095 1180 return ret;
1c6fdbd8
KO		 1181}
1182
0cc455b3 1183static inline void btree_path_copy(struct btree_trans *trans, struct btree_path *dst,
67e0dd8f
KO		 1184 struct btree_path *src)
1185{
1186 unsigned i, offset = offsetof(struct btree_path, pos);
1187
1188 memcpy((void *) dst + offset,
1189 (void *) src + offset,
1190 sizeof(struct btree_path) - offset);
1191
c81f5836
KO		 1192 for (i = 0; i < BTREE_MAX_DEPTH; i++) {
1193 unsigned t = btree_node_locked_type(dst, i);
1194
1195 if (t != BTREE_NODE_UNLOCKED)
1196 six_lock_increment(&dst->l[i].b->c.lock, t);
1197 }
67e0dd8f
KO		 1198}
1199
c404f203
KO		 1200static struct btree_path *btree_path_clone(struct btree_trans *trans, struct btree_path *src,
1201 bool intent)
67e0dd8f 1202{
c404f203 1203 struct btree_path *new = btree_path_alloc(trans, src);
67e0dd8f 1204
c404f203 1205 btree_path_copy(trans, new, src);
67e0dd8f 1206 __btree_path_get(new, intent);
c404f203
KO		 1207 return new;
1208}
1209
0cc455b3 1210__flatten
d8648425 1211struct btree_path *__bch2_btree_path_make_mut(struct btree_trans *trans,
ee2c6ea7
KO		 1212 struct btree_path *path, bool intent,
1213 unsigned long ip)
c404f203 1214{
67e0dd8f 1215 __btree_path_put(path, intent);
c404f203 1216 path = btree_path_clone(trans, path, intent);
67e0dd8f 1217 path->preserve = false;
67e0dd8f
KO		 1218 return path;
1219}
1220
ce91abd6 1221struct btree_path * __must_check
67e0dd8f 1222__bch2_btree_path_set_pos(struct btree_trans *trans,
ee2c6ea7
KO		 1223 struct btree_path *path, struct bpos new_pos,
1224 bool intent, unsigned long ip, int cmp)
67e0dd8f 1225{
12344c7c 1226 bch2_trans_verify_not_in_restart(trans);
67e0dd8f
KO		 1227 EBUG_ON(!path->ref);
1228
ee2c6ea7 1229 path = bch2_btree_path_make_mut(trans, path, intent, ip);
67e0dd8f
KO		 1230
1231 path->pos = new_pos;
67e0dd8f
KO		 1232 trans->paths_sorted = false;
1233
1234 if (unlikely(path->cached)) {
8bfe14e8 1235 btree_node_unlock(trans, path, 0);
315c9ba6 1236 path->l[0].b = ERR_PTR(-BCH_ERR_no_btree_node_up);
67e0dd8f
KO		 1237 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
1238 goto out;
1239 }
1240
cd5bd162 1241 unsigned level = btree_path_up_until_good_node(trans, path, cmp);
67e0dd8f 1242
5c792e1b
KO		 1243 if (btree_path_node(path, level)) {
1244 struct btree_path_level *l = &path->l[level];
1245
1246 BUG_ON(!btree_node_locked(path, level));
67e0dd8f
KO		 1247 /*
1248 * We might have to skip over many keys, or just a few: try
1249 * advancing the node iterator, and if we have to skip over too
1250 * many keys just reinit it (or if we're rewinding, since that
1251 * is expensive).
1252 */
1253 if (cmp < 0 ||
5c792e1b
KO		 1254 !btree_path_advance_to_pos(path, l, 8))
1255 bch2_btree_node_iter_init(&l->iter, l->b, &path->pos);
1256
1257 /*
1258 * Iterators to interior nodes should always be pointed at the first non
1259 * whiteout:
1260 */
1261 if (unlikely(level))
1262 bch2_btree_node_iter_peek(&l->iter, l->b);
67e0dd8f
KO		 1263 }
1264
5c792e1b 1265 if (unlikely(level != path->level)) {
67e0dd8f 1266 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
8bfe14e8 1267 __bch2_btree_path_unlock(trans, path);
1d3ecd7e 1268 }
67e0dd8f
KO		 1269out:
1270 bch2_btree_path_verify(trans, path);
67e0dd8f
KO		 1271 return path;
1272}
1273
67e0dd8f
KO		 1274/* Btree path: main interface: */
1275
1276static struct btree_path *have_path_at_pos(struct btree_trans *trans, struct btree_path *path)
1277{
a300261a 1278 struct btree_path *sib;
67e0dd8f 1279
a300261a
KO		 1280 sib = prev_btree_path(trans, path);
1281 if (sib && !btree_path_cmp(sib, path))
1282 return sib;
67e0dd8f 1283
a300261a
KO		 1284 sib = next_btree_path(trans, path);
1285 if (sib && !btree_path_cmp(sib, path))
1286 return sib;
67e0dd8f
KO		 1287
1288 return NULL;
1289}
1290
9a74f63c 1291static struct btree_path *have_node_at_pos(struct btree_trans *trans, struct btree_path *path)
67e0dd8f 1292{
a300261a 1293 struct btree_path *sib;
67e0dd8f 1294
a300261a
KO		 1295 sib = prev_btree_path(trans, path);
1296 if (sib && sib->level == path->level && path_l(sib)->b == path_l(path)->b)
1297 return sib;
67e0dd8f 1298
a300261a
KO		 1299 sib = next_btree_path(trans, path);
1300 if (sib && sib->level == path->level && path_l(sib)->b == path_l(path)->b)
1301 return sib;
67e0dd8f 1302
9a74f63c 1303 return NULL;
67e0dd8f
KO		 1304}
1305
1306static inline void __bch2_path_free(struct btree_trans *trans, struct btree_path *path)
08070cba 1307{
8bfe14e8 1308 __bch2_btree_path_unlock(trans, path);
67e0dd8f 1309 btree_path_list_remove(trans, path);
6e92d155 1310 __clear_bit(path->idx, trans->paths_allocated);
08070cba
KO		 1311}
1312
67e0dd8f
KO		 1313void bch2_path_put(struct btree_trans *trans, struct btree_path *path, bool intent)
1314{
1315 struct btree_path *dup;
1316
1317 EBUG_ON(trans->paths + path->idx != path);
1318 EBUG_ON(!path->ref);
1319
1320 if (!__btree_path_put(path, intent))
1321 return;
1322
a300261a
KO		 1323 dup = path->preserve
1324 ? have_path_at_pos(trans, path)
1325 : have_node_at_pos(trans, path);
1326
1327 if (!dup && !(!path->preserve && !is_btree_node(path, path->level)))
1328 return;
67e0dd8f 1329
9a74f63c 1330 if (path->should_be_locked &&
a300261a
KO		 1331 !trans->restarted &&
1332 (!dup || !bch2_btree_path_relock_norestart(trans, dup, _THIS_IP_)))
9a74f63c
KO		 1333 return;
1334
a300261a
KO		 1335 if (dup) {
1336 dup->preserve |= path->preserve;
1337 dup->should_be_locked |= path->should_be_locked;
1338 }
1339
9a74f63c 1340 __bch2_path_free(trans, path);
67e0dd8f
KO		 1341}
1342
7dcbdbd8
KO		 1343static void bch2_path_put_nokeep(struct btree_trans *trans, struct btree_path *path,
1344 bool intent)
1345{
1346 EBUG_ON(trans->paths + path->idx != path);
1347 EBUG_ON(!path->ref);
1348
1349 if (!__btree_path_put(path, intent))
1350 return;
1351
1352 __bch2_path_free(trans, path);
1353}
1354
12344c7c
KO		 1355void __noreturn bch2_trans_restart_error(struct btree_trans *trans, u32 restart_count)
1356{
1357 panic("trans->restart_count %u, should be %u, last restarted by %pS\n",
1358 trans->restart_count, restart_count,
5e2d8be8 1359 (void *) trans->last_begin_ip);
12344c7c
KO		 1360}
1361
1362void __noreturn bch2_trans_in_restart_error(struct btree_trans *trans)
1363{
1364 panic("in transaction restart: %s, last restarted by %pS\n",
1365 bch2_err_str(trans->restarted),
1366 (void *) trans->last_restarted_ip);
1367}
1368
5c0bb66a 1369noinline __cold
8570d775 1370void bch2_trans_updates_to_text(struct printbuf *buf, struct btree_trans *trans)
67e0dd8f 1371{
67e0dd8f 1372 struct btree_insert_entry *i;
2158fe46 1373
401ec4db 1374 prt_printf(buf, "transaction updates for %s journal seq %llu",
8570d775 1375 trans->fn, trans->journal_res.seq);
401ec4db
KO		 1376 prt_newline(buf);
1377 printbuf_indent_add(buf, 2);
2158fe46
KO		 1378
1379 trans_for_each_update(trans, i) {
1380 struct bkey_s_c old = { &i->old_k, i->old_v };
1381
401ec4db 1382 prt_printf(buf, "update: btree=%s cached=%u %pS",
88dfe193 1383 bch2_btree_id_str(i->btree_id),
8570d775
KO		 1384 i->cached,
1385 (void *) i->ip_allocated);
401ec4db 1386 prt_newline(buf);
8570d775 1387
401ec4db 1388 prt_printf(buf, " old ");
8570d775 1389 bch2_bkey_val_to_text(buf, trans->c, old);
401ec4db 1390 prt_newline(buf);
8570d775 1391
401ec4db 1392 prt_printf(buf, " new ");
8570d775 1393 bch2_bkey_val_to_text(buf, trans->c, bkey_i_to_s_c(i->k));
401ec4db 1394 prt_newline(buf);
2158fe46
KO		 1395 }
1396
67997234
KO		 1397 for (struct jset_entry *e = trans->journal_entries;
1398 e != btree_trans_journal_entries_top(trans);
1399 e = vstruct_next(e))
1400 bch2_journal_entry_to_text(buf, trans->c, e);
920e69bc 1401
401ec4db 1402 printbuf_indent_sub(buf, 2);
8570d775
KO		 1403}
1404
1405noinline __cold
1406void bch2_dump_trans_updates(struct btree_trans *trans)
1407{
1408 struct printbuf buf = PRINTBUF;
1409
1410 bch2_trans_updates_to_text(&buf, trans);
a8f35428 1411 bch2_print_string_as_lines(KERN_ERR, buf.buf);
8570d775 1412 printbuf_exit(&buf);
2158fe46
KO		 1413}
1414
1415noinline __cold
5c0bb66a
KO		 1416void bch2_btree_path_to_text(struct printbuf *out, struct btree_path *path)
1417{
1418 prt_printf(out, "path: idx %2u ref %u:%u %c %c btree=%s l=%u pos ",
1419 path->idx, path->ref, path->intent_ref,
1420 path->preserve ? 'P' : ' ',
1421 path->should_be_locked ? 'S' : ' ',
88dfe193 1422 bch2_btree_id_str(path->btree_id),
5c0bb66a
KO		 1423 path->level);
1424 bch2_bpos_to_text(out, path->pos);
1425
1426 prt_printf(out, " locks %u", path->nodes_locked);
94c69faf 1427#ifdef TRACK_PATH_ALLOCATED
5c0bb66a
KO		 1428 prt_printf(out, " %pS", (void *) path->ip_allocated);
1429#endif
1430 prt_newline(out);
1431}
1432
73bd774d 1433static noinline __cold
5c0bb66a
KO		 1434void __bch2_trans_paths_to_text(struct printbuf *out, struct btree_trans *trans,
1435 bool nosort)
2158fe46
KO		 1436{
1437 struct btree_path *path;
67e0dd8f 1438 unsigned idx;
67e0dd8f 1439
5c0bb66a
KO		 1440 if (!nosort)
1441 btree_trans_sort_paths(trans);
67e0dd8f 1442
5c0bb66a
KO		 1443 trans_for_each_path_inorder(trans, path, idx)
1444 bch2_btree_path_to_text(out, path);
1445}
fa8e94fa 1446
5c0bb66a
KO		 1447noinline __cold
1448void bch2_trans_paths_to_text(struct printbuf *out, struct btree_trans *trans)
1449{
1450 __bch2_trans_paths_to_text(out, trans, false);
1451}
fa8e94fa 1452
73bd774d 1453static noinline __cold
5c0bb66a
KO		 1454void __bch2_dump_trans_paths_updates(struct btree_trans *trans, bool nosort)
1455{
1456 struct printbuf buf = PRINTBUF;
1457
1458 __bch2_trans_paths_to_text(&buf, trans, nosort);
a8f35428 1459 bch2_trans_updates_to_text(&buf, trans);
67e0dd8f 1460
a8f35428 1461 bch2_print_string_as_lines(KERN_ERR, buf.buf);
2158fe46 1462 printbuf_exit(&buf);
67e0dd8f
KO		 1463}
1464
5c0bb66a
KO		 1465noinline __cold
1466void bch2_dump_trans_paths_updates(struct btree_trans *trans)
1467{
1468 __bch2_dump_trans_paths_updates(trans, false);
1469}
1470
1471noinline __cold
1472static void bch2_trans_update_max_paths(struct btree_trans *trans)
1473{
1474 struct btree_transaction_stats *s = btree_trans_stats(trans);
1475 struct printbuf buf = PRINTBUF;
6e92d155 1476 size_t nr = bitmap_weight(trans->paths_allocated, BTREE_ITER_MAX);
5c0bb66a
KO		 1477
1478 if (!s)
1479 return;
1480
1481 bch2_trans_paths_to_text(&buf, trans);
1482
1483 if (!buf.allocation_failure) {
1484 mutex_lock(&s->lock);
6e92d155
KO		 1485 if (nr > s->nr_max_paths) {
1486 s->nr_max_paths = nr;
5c0bb66a
KO		 1487 swap(s->max_paths_text, buf.buf);
1488 }
1489 mutex_unlock(&s->lock);
1490 }
1491
1492 printbuf_exit(&buf);
1493
6e92d155 1494 trans->nr_max_paths = nr;
5c0bb66a
KO		 1495}
1496
e153a0d7
KO		 1497noinline __cold
1498int __bch2_btree_trans_too_many_iters(struct btree_trans *trans)
1499{
1500 if (trace_trans_restart_too_many_iters_enabled()) {
1501 struct printbuf buf = PRINTBUF;
1502
1503 bch2_trans_paths_to_text(&buf, trans);
1504 trace_trans_restart_too_many_iters(trans, _THIS_IP_, buf.buf);
1505 printbuf_exit(&buf);
1506 }
1507
1508 count_event(trans->c, trans_restart_too_many_iters);
1509
1510 return btree_trans_restart(trans, BCH_ERR_transaction_restart_too_many_iters);
1511}
1512
3f3bc66e
KO		 1513static noinline void btree_path_overflow(struct btree_trans *trans)
1514{
1515 bch2_dump_trans_paths_updates(trans);
6bf3766b 1516 panic("trans path overflow\n");
3f3bc66e
KO		 1517}
1518
1519static inline struct btree_path *btree_path_alloc(struct btree_trans *trans,
1520 struct btree_path *pos)
67e0dd8f
KO		 1521{
1522 struct btree_path *path;
6e92d155 1523 size_t idx = find_first_zero_bit(trans->paths_allocated, BTREE_ITER_MAX);
67e0dd8f 1524
6e92d155 1525 if (unlikely(idx == BTREE_ITER_MAX))
3f3bc66e 1526 btree_path_overflow(trans);
67e0dd8f 1527
6e92d155 1528 BUG_ON(idx > BTREE_ITER_MAX);
992fa4e6
KO		 1529
1530 /*
1531 * Do this before marking the new path as allocated, since it won't be
1532 * initialized yet:
1533 */
1534 if (unlikely(idx > trans->nr_max_paths))
1535 bch2_trans_update_max_paths(trans);
1536
6e92d155 1537 __set_bit(idx, trans->paths_allocated);
67e0dd8f
KO		 1538
1539 path = &trans->paths[idx];
67e0dd8f
KO		 1540 path->idx = idx;
1541 path->ref = 0;
1542 path->intent_ref = 0;
1543 path->nodes_locked = 0;
67e0dd8f
KO		 1544
1545 btree_path_list_add(trans, pos, path);
5c0bb66a 1546 trans->paths_sorted = false;
67e0dd8f
KO		 1547 return path;
1548}
1549
f3e1f444 1550struct btree_path *bch2_path_get(struct btree_trans *trans,
67e0dd8f
KO		 1551 enum btree_id btree_id, struct bpos pos,
1552 unsigned locks_want, unsigned level,
ee2c6ea7 1553 unsigned flags, unsigned long ip)
67e0dd8f 1554{
807dda8c 1555 struct btree_path *path, *path_pos = NULL;
f3e1f444
KO		 1556 bool cached = flags & BTREE_ITER_CACHED;
1557 bool intent = flags & BTREE_ITER_INTENT;
67e0dd8f
KO		 1558 int i;
1559
12344c7c 1560 bch2_trans_verify_not_in_restart(trans);
7071878b
KO		 1561 bch2_trans_verify_locks(trans);
1562
eb7bd15f 1563 btree_trans_sort_paths(trans);
67e0dd8f 1564
807dda8c
KO		 1565 trans_for_each_path_inorder(trans, path, i) {
1566 if (__btree_path_cmp(path,
1567 btree_id,
1568 cached,
1569 pos,
1570 level) > 0)
1571 break;
67e0dd8f 1572
807dda8c 1573 path_pos = path;
67e0dd8f
KO		 1574 }
1575
807dda8c
KO		 1576 if (path_pos &&
1577 path_pos->cached == cached &&
1578 path_pos->btree_id == btree_id &&
1579 path_pos->level == level) {
1580 __btree_path_get(path_pos, intent);
ee2c6ea7 1581 path = bch2_btree_path_set_pos(trans, path_pos, pos, intent, ip);
67e0dd8f 1582 } else {
807dda8c
KO		 1583 path = btree_path_alloc(trans, path_pos);
1584 path_pos = NULL;
67e0dd8f
KO		 1585
1586 __btree_path_get(path, intent);
1587 path->pos = pos;
1588 path->btree_id = btree_id;
1589 path->cached = cached;
67e0dd8f
KO		 1590 path->uptodate = BTREE_ITER_NEED_TRAVERSE;
1591 path->should_be_locked = false;
1592 path->level = level;
1593 path->locks_want = locks_want;
1594 path->nodes_locked = 0;
67e0dd8f 1595 for (i = 0; i < ARRAY_SIZE(path->l); i++)
315c9ba6 1596 path->l[i].b = ERR_PTR(-BCH_ERR_no_btree_node_init);
94c69faf 1597#ifdef TRACK_PATH_ALLOCATED
ee2c6ea7 1598 path->ip_allocated = ip;
67e0dd8f
KO		 1599#endif
1600 trans->paths_sorted = false;
1601 }
1602
f3e1f444
KO		 1603 if (!(flags & BTREE_ITER_NOPRESERVE))
1604 path->preserve = true;
1605
67e0dd8f
KO		 1606 if (path->intent_ref)
1607 locks_want = max(locks_want, level + 1);
1608
1609 /*
1610 * If the path has locks_want greater than requested, we don't downgrade
1611 * it here - on transaction restart because btree node split needs to
1612 * upgrade locks, we might be putting/getting the iterator again.
1613 * Downgrading iterators only happens via bch2_trans_downgrade(), after
1614 * a successful transaction commit.
1615 */
1616
1617 locks_want = min(locks_want, BTREE_MAX_DEPTH);
cd5afabe 1618 if (locks_want > path->locks_want)
be9e782d 1619 bch2_btree_path_upgrade_noupgrade_sibs(trans, path, locks_want, NULL);
67e0dd8f 1620
67e0dd8f
KO		 1621 return path;
1622}
1623
b2d1d56b 1624struct bkey_s_c bch2_btree_path_peek_slot(struct btree_path *path, struct bkey *u)
67e0dd8f
KO		 1625{
1626
f42238b5
KO		 1627 struct btree_path_level *l = path_l(path);
1628 struct bkey_packed *_k;
67e0dd8f
KO		 1629 struct bkey_s_c k;
1630
f42238b5
KO		 1631 if (unlikely(!l->b))
1632 return bkey_s_c_null;
f7b6ca23 1633
f42238b5
KO		 1634 EBUG_ON(path->uptodate != BTREE_ITER_UPTODATE);
1635 EBUG_ON(!btree_node_locked(path, path->level));
67e0dd8f 1636
f42238b5 1637 if (!path->cached) {
f7b6ca23 1638 _k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
67e0dd8f
KO		 1639 k = _k ? bkey_disassemble(l->b, _k, u) : bkey_s_c_null;
1640
e88a75eb 1641 EBUG_ON(k.k && bkey_deleted(k.k) && bpos_eq(k.k->p, path->pos));
67e0dd8f 1642
e88a75eb 1643 if (!k.k || !bpos_eq(path->pos, k.k->p))
67e0dd8f
KO		 1644 goto hole;
1645 } else {
1646 struct bkey_cached *ck = (void *) path->l[0].b;
1647
f7b6ca23
KO		 1648 EBUG_ON(ck &&
1649 (path->btree_id != ck->key.btree_id ||
e88a75eb 1650 !bkey_eq(path->pos, ck->key.pos)));
087e53c2
KO		 1651 if (!ck || !ck->valid)
1652 return bkey_s_c_null;
67e0dd8f 1653
2e63e180 1654 *u = ck->k->k;
67e0dd8f
KO		 1655 k = bkey_i_to_s_c(ck->k);
1656 }
1657
1658 return k;
1659hole:
1660 bkey_init(u);
1661 u->p = path->pos;
1662 return (struct bkey_s_c) { u, NULL };
1663}
1664
1665/* Btree iterators: */
1666
db92f2ea
KO		 1667int __must_check
1668__bch2_btree_iter_traverse(struct btree_iter *iter)
1669{
1670 return bch2_btree_path_traverse(iter->trans, iter->path, iter->flags);
1671}
1672
08070cba
KO		 1673int __must_check
1674bch2_btree_iter_traverse(struct btree_iter *iter)
1675{
66a0a497
KO		 1676 int ret;
1677
ce91abd6 1678 iter->path = bch2_btree_path_set_pos(iter->trans, iter->path,
67e0dd8f 1679 btree_iter_search_key(iter),
ee2c6ea7
KO		 1680 iter->flags & BTREE_ITER_INTENT,
1681 btree_iter_ip_allocated(iter));
08070cba 1682
67e0dd8f 1683 ret = bch2_btree_path_traverse(iter->trans, iter->path, iter->flags);
66a0a497
KO		 1684 if (ret)
1685 return ret;
1686
fd211bc7 1687 btree_path_set_should_be_locked(iter->path);
66a0a497 1688 return 0;
08070cba
KO		 1689}
1690
1c6fdbd8
KO		 1691/* Iterate across nodes (leaf and interior nodes) */
1692
1693struct btree *bch2_btree_iter_peek_node(struct btree_iter *iter)
1694{
502027a8 1695 struct btree_trans *trans = iter->trans;
f21566f1 1696 struct btree *b = NULL;
1c6fdbd8
KO		 1697 int ret;
1698
67e0dd8f 1699 EBUG_ON(iter->path->cached);
7e1a3aa9 1700 bch2_btree_iter_verify(iter);
1c6fdbd8 1701
502027a8 1702 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
1c6fdbd8 1703 if (ret)
d355c6f4 1704 goto err;
1c6fdbd8 1705
67e0dd8f 1706 b = btree_path_node(iter->path, iter->path->level);
1c6fdbd8 1707 if (!b)
f21566f1 1708 goto out;
1c6fdbd8 1709
e88a75eb 1710 BUG_ON(bpos_lt(b->key.k.p, iter->pos));
1c6fdbd8 1711
f21566f1 1712 bkey_init(&iter->k);
67e0dd8f 1713 iter->k.p = iter->pos = b->key.k.p;
502027a8 1714
ce91abd6 1715 iter->path = bch2_btree_path_set_pos(trans, iter->path, b->key.k.p,
ee2c6ea7
KO		 1716 iter->flags & BTREE_ITER_INTENT,
1717 btree_iter_ip_allocated(iter));
fd211bc7 1718 btree_path_set_should_be_locked(iter->path);
f21566f1
KO		 1719out:
1720 bch2_btree_iter_verify_entry_exit(iter);
1721 bch2_btree_iter_verify(iter);
2dac0eae 1722
1c6fdbd8 1723 return b;
d355c6f4
KO		 1724err:
1725 b = ERR_PTR(ret);
1726 goto out;
1c6fdbd8
KO		 1727}
1728
511b629a
KO		 1729struct btree *bch2_btree_iter_peek_node_and_restart(struct btree_iter *iter)
1730{
1731 struct btree *b;
1732
1733 while (b = bch2_btree_iter_peek_node(iter),
1734 bch2_err_matches(PTR_ERR_OR_ZERO(b), BCH_ERR_transaction_restart))
1735 bch2_trans_begin(iter->trans);
1736
1737 return b;
1738}
1739
2dac0eae 1740struct btree *bch2_btree_iter_next_node(struct btree_iter *iter)
1c6fdbd8 1741{
67e0dd8f
KO		 1742 struct btree_trans *trans = iter->trans;
1743 struct btree_path *path = iter->path;
f21566f1 1744 struct btree *b = NULL;
1c6fdbd8
KO		 1745 int ret;
1746
12344c7c 1747 bch2_trans_verify_not_in_restart(trans);
67e0dd8f 1748 EBUG_ON(iter->path->cached);
7e1a3aa9 1749 bch2_btree_iter_verify(iter);
1c6fdbd8 1750
979735df 1751 /* already at end? */
67e0dd8f 1752 if (!btree_path_node(path, path->level))
979735df 1753 return NULL;
1c6fdbd8 1754
979735df
KO		 1755 /* got to end? */
1756 if (!btree_path_node(path, path->level + 1)) {
8bfe14e8 1757 btree_path_set_level_up(trans, path);
979735df
KO		 1758 return NULL;
1759 }
1c6fdbd8 1760
979735df 1761 if (!bch2_btree_node_relock(trans, path, path->level + 1)) {
8bfe14e8 1762 __bch2_btree_path_unlock(trans, path);
315c9ba6
KO		 1763 path->l[path->level].b = ERR_PTR(-BCH_ERR_no_btree_node_relock);
1764 path->l[path->level + 1].b = ERR_PTR(-BCH_ERR_no_btree_node_relock);
7071878b 1765 btree_path_set_dirty(path, BTREE_ITER_NEED_TRAVERSE);
674cfc26 1766 trace_and_count(trans->c, trans_restart_relock_next_node, trans, _THIS_IP_, path);
549d173c 1767 ret = btree_trans_restart(trans, BCH_ERR_transaction_restart_relock);
d355c6f4 1768 goto err;
979735df 1769 }
1c6fdbd8 1770
979735df 1771 b = btree_path_node(path, path->level + 1);
1c6fdbd8 1772
e88a75eb 1773 if (bpos_eq(iter->pos, b->key.k.p)) {
315c9ba6 1774 __btree_path_set_level_up(trans, path, path->level++);
979735df 1775 } else {
1c6fdbd8
KO		 1776 /*
1777 * Haven't gotten to the end of the parent node: go back down to
1778 * the next child node
1779 */
67e0dd8f 1780 path = iter->path =
ce91abd6 1781 bch2_btree_path_set_pos(trans, path, bpos_successor(iter->pos),
ee2c6ea7
KO		 1782 iter->flags & BTREE_ITER_INTENT,
1783 btree_iter_ip_allocated(iter));
1c6fdbd8 1784
c4bce586 1785 btree_path_set_level_down(trans, path, iter->min_depth);
345ca825 1786
67e0dd8f 1787 ret = bch2_btree_path_traverse(trans, path, iter->flags);
d355c6f4
KO		 1788 if (ret)
1789 goto err;
1c6fdbd8 1790
67e0dd8f 1791 b = path->l[path->level].b;
1c6fdbd8
KO		 1792 }
1793
f21566f1 1794 bkey_init(&iter->k);
67e0dd8f 1795 iter->k.p = iter->pos = b->key.k.p;
502027a8 1796
ce91abd6 1797 iter->path = bch2_btree_path_set_pos(trans, iter->path, b->key.k.p,
ee2c6ea7
KO		 1798 iter->flags & BTREE_ITER_INTENT,
1799 btree_iter_ip_allocated(iter));
fd211bc7 1800 btree_path_set_should_be_locked(iter->path);
502027a8 1801 BUG_ON(iter->path->uptodate);
f21566f1
KO		 1802out:
1803 bch2_btree_iter_verify_entry_exit(iter);
1804 bch2_btree_iter_verify(iter);
2dac0eae 1805
1c6fdbd8 1806 return b;
d355c6f4
KO		 1807err:
1808 b = ERR_PTR(ret);
1809 goto out;
1c6fdbd8
KO		 1810}
1811
1812/* Iterate across keys (in leaf nodes only) */
1813
e0ba3b64 1814inline bool bch2_btree_iter_advance(struct btree_iter *iter)
434094be 1815{
e56978c8
KO		 1816 struct bpos pos = iter->k.p;
1817 bool ret = !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS
1818 ? bpos_eq(pos, SPOS_MAX)
1819 : bkey_eq(pos, SPOS_MAX));
3d495595 1820
e56978c8
KO		 1821 if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
1822 pos = bkey_successor(iter, pos);
1823 bch2_btree_iter_set_pos(iter, pos);
1824 return ret;
3d495595
KO		 1825}
1826
e0ba3b64 1827inline bool bch2_btree_iter_rewind(struct btree_iter *iter)
3d495595
KO		 1828{
1829 struct bpos pos = bkey_start_pos(&iter->k);
e88a75eb
KO		 1830 bool ret = !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS
1831 ? bpos_eq(pos, POS_MIN)
1832 : bkey_eq(pos, POS_MIN));
3d495595 1833
7e1a3aa9 1834 if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
e751c01a 1835 pos = bkey_predecessor(iter, pos);
3d495595 1836 bch2_btree_iter_set_pos(iter, pos);
7e1a3aa9 1837 return ret;
434094be
KO		 1838}
1839
3763cb95 1840static noinline
67e0dd8f 1841struct bkey_i *__bch2_btree_trans_peek_updates(struct btree_iter *iter)
818664f5
KO		 1842{
1843 struct btree_insert_entry *i;
5288e66a 1844 struct bkey_i *ret = NULL;
818664f5 1845
8e6bbc41 1846 trans_for_each_update(iter->trans, i) {
5288e66a
KO		 1847 if (i->btree_id < iter->btree_id)
1848 continue;
1849 if (i->btree_id > iter->btree_id)
818664f5 1850 break;
e88a75eb 1851 if (bpos_lt(i->k->k.p, iter->path->pos))
5288e66a 1852 continue;
12ce5b7d
KO		 1853 if (i->key_cache_already_flushed)
1854 continue;
e88a75eb 1855 if (!ret || bpos_lt(i->k->k.p, ret->k.p))
5288e66a
KO		 1856 ret = i->k;
1857 }
818664f5 1858
5288e66a
KO		 1859 return ret;
1860}
1861
3763cb95
KO		 1862static inline struct bkey_i *btree_trans_peek_updates(struct btree_iter *iter)
1863{
1864 return iter->flags & BTREE_ITER_WITH_UPDATES
1865 ? __bch2_btree_trans_peek_updates(iter)
1866 : NULL;
1867}
1868
73bd774d
KO		 1869static struct bkey_i *bch2_btree_journal_peek(struct btree_trans *trans,
1870 struct btree_iter *iter,
1871 struct bpos end_pos)
30525f68 1872{
ad9c7992
KO		 1873 return bch2_journal_keys_peek_upto(trans->c, iter->btree_id,
1874 iter->path->level,
1875 iter->path->pos,
1876 end_pos,
1877 &iter->journal_idx);
30525f68
KO		 1878}
1879
5222a460
KO		 1880static noinline
1881struct bkey_s_c btree_trans_peek_slot_journal(struct btree_trans *trans,
1882 struct btree_iter *iter)
1883{
30525f68 1884 struct bkey_i *k = bch2_btree_journal_peek(trans, iter, iter->path->pos);
5222a460 1885
5650bb46 1886 if (k) {
5222a460
KO		 1887 iter->k = k->k;
1888 return bkey_i_to_s_c(k);
1889 } else {
1890 return bkey_s_c_null;
1891 }
1892}
1893
1894static noinline
1895struct bkey_s_c btree_trans_peek_journal(struct btree_trans *trans,
1896 struct btree_iter *iter,
1897 struct bkey_s_c k)
1898{
1899 struct bkey_i *next_journal =
30525f68 1900 bch2_btree_journal_peek(trans, iter,
c167f9e5 1901 k.k ? k.k->p : path_l(iter->path)->b->key.k.p);
5222a460 1902
5650bb46 1903 if (next_journal) {
5222a460
KO		 1904 iter->k = next_journal->k;
1905 k = bkey_i_to_s_c(next_journal);
1906 }
1907
1908 return k;
1909}
1910
f7b6ca23
KO		 1911/*
1912 * Checks btree key cache for key at iter->pos and returns it if present, or
1913 * bkey_s_c_null:
1914 */
1915static noinline
dcced069 1916struct bkey_s_c btree_trans_peek_key_cache(struct btree_iter *iter, struct bpos pos)
f7b6ca23
KO		 1917{
1918 struct btree_trans *trans = iter->trans;
1919 struct bch_fs *c = trans->c;
1920 struct bkey u;
52bf51b9 1921 struct bkey_s_c k;
f7b6ca23
KO		 1922 int ret;
1923
1617d56d
KO		 1924 if ((iter->flags & BTREE_ITER_KEY_CACHE_FILL) &&
1925 bpos_eq(iter->pos, pos))
1926 return bkey_s_c_null;
1927
f7b6ca23
KO		 1928 if (!bch2_btree_key_cache_find(c, iter->btree_id, pos))
1929 return bkey_s_c_null;
1930
1931 if (!iter->key_cache_path)
1932 iter->key_cache_path = bch2_path_get(trans, iter->btree_id, pos,
1933 iter->flags & BTREE_ITER_INTENT, 0,
087e53c2 1934 iter->flags|BTREE_ITER_CACHED|
ee2c6ea7
KO		 1935 BTREE_ITER_CACHED_NOFILL,
1936 _THIS_IP_);
f7b6ca23
KO		 1937
1938 iter->key_cache_path = bch2_btree_path_set_pos(trans, iter->key_cache_path, pos,
ee2c6ea7
KO		 1939 iter->flags & BTREE_ITER_INTENT,
1940 btree_iter_ip_allocated(iter));
f7b6ca23 1941
dcced069
KO		 1942 ret = bch2_btree_path_traverse(trans, iter->key_cache_path,
1943 iter->flags|BTREE_ITER_CACHED) ?:
1944 bch2_btree_path_relock(trans, iter->path, _THIS_IP_);
f7b6ca23
KO		 1945 if (unlikely(ret))
1946 return bkey_s_c_err(ret);
1947
fd211bc7 1948 btree_path_set_should_be_locked(iter->key_cache_path);
f7b6ca23 1949
52bf51b9
KO		 1950 k = bch2_btree_path_peek_slot(iter->key_cache_path, &u);
1951 if (k.k && !bkey_err(k)) {
1952 iter->k = u;
1953 k.k = &iter->k;
1954 }
1955 return k;
f7b6ca23
KO		 1956}
1957
a1e82d35 1958static struct bkey_s_c __bch2_btree_iter_peek(struct btree_iter *iter, struct bpos search_key)
1c6fdbd8 1959{
67e0dd8f 1960 struct btree_trans *trans = iter->trans;
360746bf 1961 struct bkey_i *next_update;
f7b6ca23 1962 struct bkey_s_c k, k2;
8e432d98 1963 int ret;
1c6fdbd8 1964
969576ec 1965 EBUG_ON(iter->path->cached);
7e1a3aa9 1966 bch2_btree_iter_verify(iter);
1c6fdbd8 1967
1c6fdbd8 1968 while (1) {
969576ec
KO		 1969 struct btree_path_level *l;
1970
ce91abd6 1971 iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key,
ee2c6ea7
KO		 1972 iter->flags & BTREE_ITER_INTENT,
1973 btree_iter_ip_allocated(iter));
c8476a4e 1974
67e0dd8f 1975 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
e6e024e9
KO		 1976 if (unlikely(ret)) {
1977 /* ensure that iter->k is consistent with iter->pos: */
1978 bch2_btree_iter_set_pos(iter, iter->pos);
1979 k = bkey_s_c_err(ret);
1980 goto out;
1981 }
1c6fdbd8 1982
969576ec
KO		 1983 l = path_l(iter->path);
1984
1985 if (unlikely(!l->b)) {
1986 /* No btree nodes at requested level: */
1987 bch2_btree_iter_set_pos(iter, SPOS_MAX);
1988 k = bkey_s_c_null;
1989 goto out;
1990 }
1991
fd211bc7 1992 btree_path_set_should_be_locked(iter->path);
f7b6ca23 1993
969576ec 1994 k = btree_path_level_peek_all(trans->c, l, &iter->k);
e6e024e9 1995
f7b6ca23
KO		 1996 if (unlikely(iter->flags & BTREE_ITER_WITH_KEY_CACHE) &&
1997 k.k &&
1998 (k2 = btree_trans_peek_key_cache(iter, k.k->p)).k) {
8192f8a5
KO		 1999 k = k2;
2000 ret = bkey_err(k);
f7b6ca23 2001 if (ret) {
f7b6ca23
KO		 2002 bch2_btree_iter_set_pos(iter, iter->pos);
2003 goto out;
2004 }
f7b6ca23
KO		 2005 }
2006
5222a460
KO		 2007 if (unlikely(iter->flags & BTREE_ITER_WITH_JOURNAL))
2008 k = btree_trans_peek_journal(trans, iter, k);
2009
2010 next_update = btree_trans_peek_updates(iter);
e6e024e9 2011
818664f5 2012 if (next_update &&
e88a75eb
KO		 2013 bpos_le(next_update->k.p,
2014 k.k ? k.k->p : l->b->key.k.p)) {
5288e66a 2015 iter->k = next_update->k;
818664f5 2016 k = bkey_i_to_s_c(next_update);
5288e66a 2017 }
818664f5 2018
5222a460
KO		 2019 if (k.k && bkey_deleted(k.k)) {
2020 /*
2021 * If we've got a whiteout, and it's after the search
2022 * key, advance the search key to the whiteout instead
2023 * of just after the whiteout - it might be a btree
2024 * whiteout, with a real key at the same position, since
2025 * in the btree deleted keys sort before non deleted.
2026 */
e88a75eb 2027 search_key = !bpos_eq(search_key, k.k->p)
5222a460
KO		 2028 ? k.k->p
2029 : bpos_successor(k.k->p);
2030 continue;
2031 }
2032
818664f5 2033 if (likely(k.k)) {
c075ff70 2034 break;
e88a75eb 2035 } else if (likely(!bpos_eq(l->b->key.k.p, SPOS_MAX))) {
e6e024e9 2036 /* Advance to next leaf node: */
969576ec 2037 search_key = bpos_successor(l->b->key.k.p);
e6e024e9
KO		 2038 } else {
2039 /* End of btree: */
c8476a4e
KO		 2040 bch2_btree_iter_set_pos(iter, SPOS_MAX);
2041 k = bkey_s_c_null;
2042 goto out;
2043 }
1c6fdbd8 2044 }
a1e82d35 2045out:
a1e82d35
KO		 2046 bch2_btree_iter_verify(iter);
2047
2048 return k;
2049}
2050
2051/**
96dea3d5
KO		 2052 * bch2_btree_iter_peek_upto() - returns first key greater than or equal to
2053 * iterator's current position
2054 * @iter: iterator to peek from
2055 * @end: search limit: returns keys less than or equal to @end
2056 *
2057 * Returns: key if found, or an error extractable with bkey_err().
a1e82d35 2058 */
85d8cf16 2059struct bkey_s_c bch2_btree_iter_peek_upto(struct btree_iter *iter, struct bpos end)
a1e82d35
KO		 2060{
2061 struct btree_trans *trans = iter->trans;
2062 struct bpos search_key = btree_iter_search_key(iter);
2063 struct bkey_s_c k;
85d8cf16 2064 struct bpos iter_pos;
a1e82d35
KO		 2065 int ret;
2066
c72f687a 2067 EBUG_ON((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) && bkey_eq(end, POS_MAX));
b0babf2a 2068
1f2d9192 2069 if (iter->update_path) {
7dcbdbd8
KO		 2070 bch2_path_put_nokeep(trans, iter->update_path,
2071 iter->flags & BTREE_ITER_INTENT);
1f2d9192
KO		 2072 iter->update_path = NULL;
2073 }
2074
a1e82d35
KO		 2075 bch2_btree_iter_verify_entry_exit(iter);
2076
2077 while (1) {
2078 k = __bch2_btree_iter_peek(iter, search_key);
c72f687a
KO		 2079 if (unlikely(!k.k))
2080 goto end;
2081 if (unlikely(bkey_err(k)))
fd211bc7 2082 goto out_no_locked;
a1e82d35 2083
85d8cf16 2084 /*
fa014953
KO		 2085 * We need to check against @end before FILTER_SNAPSHOTS because
2086 * if we get to a different inode that requested we might be
2087 * seeing keys for a different snapshot tree that will all be
2088 * filtered out.
2089 *
2090 * But we can't do the full check here, because bkey_start_pos()
2091 * isn't monotonically increasing before FILTER_SNAPSHOTS, and
2092 * that's what we check against in extents mode:
85d8cf16 2093 */
fa014953 2094 if (k.k->p.inode > end.inode)
c72f687a 2095 goto end;
85d8cf16 2096
1f2d9192 2097 if (iter->update_path &&
e88a75eb 2098 !bkey_eq(iter->update_path->pos, k.k->p)) {
7dcbdbd8
KO		 2099 bch2_path_put_nokeep(trans, iter->update_path,
2100 iter->flags & BTREE_ITER_INTENT);
1f2d9192
KO		 2101 iter->update_path = NULL;
2102 }
2103
2104 if ((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) &&
2105 (iter->flags & BTREE_ITER_INTENT) &&
2106 !(iter->flags & BTREE_ITER_IS_EXTENTS) &&
2107 !iter->update_path) {
2108 struct bpos pos = k.k->p;
2109
2110 if (pos.snapshot < iter->snapshot) {
2111 search_key = bpos_successor(k.k->p);
2112 continue;
2113 }
2114
2115 pos.snapshot = iter->snapshot;
2116
2117 /*
2118 * advance, same as on exit for iter->path, but only up
2119 * to snapshot
2120 */
2121 __btree_path_get(iter->path, iter->flags & BTREE_ITER_INTENT);
2122 iter->update_path = iter->path;
2123
ce91abd6 2124 iter->update_path = bch2_btree_path_set_pos(trans,
1f2d9192 2125 iter->update_path, pos,
ee2c6ea7
KO		 2126 iter->flags & BTREE_ITER_INTENT,
2127 _THIS_IP_);
ef073286
KO		 2128 ret = bch2_btree_path_traverse(trans, iter->update_path, iter->flags);
2129 if (unlikely(ret)) {
2130 k = bkey_s_c_err(ret);
2131 goto out_no_locked;
2132 }
1f2d9192
KO		 2133 }
2134
a1e82d35
KO		 2135 /*
2136 * We can never have a key in a leaf node at POS_MAX, so
2137 * we don't have to check these successor() calls:
2138 */
2139 if ((iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) &&
2140 !bch2_snapshot_is_ancestor(trans->c,
2141 iter->snapshot,
2142 k.k->p.snapshot)) {
2143 search_key = bpos_successor(k.k->p);
2144 continue;
2145 }
2146
2147 if (bkey_whiteout(k.k) &&
2148 !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS)) {
2149 search_key = bkey_successor(iter, k.k->p);
2150 continue;
2151 }
2152
fa014953
KO		 2153 /*
2154 * iter->pos should be mononotically increasing, and always be
2155 * equal to the key we just returned - except extents can
2156 * straddle iter->pos:
2157 */
2158 if (!(iter->flags & BTREE_ITER_IS_EXTENTS))
2159 iter_pos = k.k->p;
2160 else
2161 iter_pos = bkey_max(iter->pos, bkey_start_pos(k.k));
2162
2163 if (unlikely(!(iter->flags & BTREE_ITER_IS_EXTENTS)
2164 ? bkey_gt(iter_pos, end)
2165 : bkey_ge(iter_pos, end)))
2166 goto end;
2167
a1e82d35
KO		 2168 break;
2169 }
2170
85d8cf16 2171 iter->pos = iter_pos;
1f2d9192 2172
ce91abd6 2173 iter->path = bch2_btree_path_set_pos(trans, iter->path, k.k->p,
ee2c6ea7
KO		 2174 iter->flags & BTREE_ITER_INTENT,
2175 btree_iter_ip_allocated(iter));
fd211bc7
KO		 2176
2177 btree_path_set_should_be_locked(iter->path);
2178out_no_locked:
1f2d9192 2179 if (iter->update_path) {
549d173c 2180 ret = bch2_btree_path_relock(trans, iter->update_path, _THIS_IP_);
fd211bc7 2181 if (unlikely(ret))
549d173c 2182 k = bkey_s_c_err(ret);
fd211bc7
KO		 2183 else
2184 btree_path_set_should_be_locked(iter->update_path);
1f2d9192 2185 }
1f2d9192 2186
a1e82d35 2187 if (!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS))
c075ff70
KO		 2188 iter->pos.snapshot = iter->snapshot;
2189
a1e82d35
KO		 2190 ret = bch2_btree_iter_verify_ret(iter, k);
2191 if (unlikely(ret)) {
2192 bch2_btree_iter_set_pos(iter, iter->pos);
2193 k = bkey_s_c_err(ret);
2194 }
67e0dd8f 2195
7e1a3aa9 2196 bch2_btree_iter_verify_entry_exit(iter);
c075ff70 2197
1c6fdbd8 2198 return k;
c72f687a
KO		 2199end:
2200 bch2_btree_iter_set_pos(iter, end);
2201 k = bkey_s_c_null;
2202 goto out_no_locked;
1c6fdbd8
KO		 2203}
2204
f4b61341 2205/**
96dea3d5 2206 * bch2_btree_iter_next() - returns first key greater than iterator's current
f4b61341 2207 * position
96dea3d5
KO		 2208 * @iter: iterator to peek from
2209 *
2210 * Returns: key if found, or an error extractable with bkey_err().
f4b61341 2211 */
1c6fdbd8
KO		 2212struct bkey_s_c bch2_btree_iter_next(struct btree_iter *iter)
2213{
e0ba3b64 2214 if (!bch2_btree_iter_advance(iter))
2e70ce56 2215 return bkey_s_c_null;
f4b61341 2216
2dac0eae 2217 return bch2_btree_iter_peek(iter);
1c6fdbd8
KO		 2218}
2219
ccf5a109 2220/**
96dea3d5 2221 * bch2_btree_iter_peek_prev() - returns first key less than or equal to
ccf5a109 2222 * iterator's current position
96dea3d5
KO		 2223 * @iter: iterator to peek from
2224 *
2225 * Returns: key if found, or an error extractable with bkey_err().
ccf5a109
KO		 2226 */
2227struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *iter)
1c6fdbd8 2228{
67e0dd8f 2229 struct btree_trans *trans = iter->trans;
c8476a4e 2230 struct bpos search_key = iter->pos;
c075ff70 2231 struct btree_path *saved_path = NULL;
1c6fdbd8 2232 struct bkey_s_c k;
c075ff70
KO		 2233 struct bkey saved_k;
2234 const struct bch_val *saved_v;
1c6fdbd8
KO		 2235 int ret;
2236
67e0dd8f 2237 EBUG_ON(iter->path->cached || iter->path->level);
5288e66a 2238 EBUG_ON(iter->flags & BTREE_ITER_WITH_UPDATES);
5222a460
KO		 2239
2240 if (iter->flags & BTREE_ITER_WITH_JOURNAL)
2241 return bkey_s_c_err(-EIO);
2242
7e1a3aa9
KO		 2243 bch2_btree_iter_verify(iter);
2244 bch2_btree_iter_verify_entry_exit(iter);
2245
c075ff70
KO		 2246 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)
2247 search_key.snapshot = U32_MAX;
2248
1c6fdbd8 2249 while (1) {
ce91abd6 2250 iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key,
ee2c6ea7
KO		 2251 iter->flags & BTREE_ITER_INTENT,
2252 btree_iter_ip_allocated(iter));
c8476a4e 2253
67e0dd8f 2254 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
7e1a3aa9 2255 if (unlikely(ret)) {
e6e024e9
KO		 2256 /* ensure that iter->k is consistent with iter->pos: */
2257 bch2_btree_iter_set_pos(iter, iter->pos);
7e1a3aa9 2258 k = bkey_s_c_err(ret);
fd211bc7 2259 goto out_no_locked;
7e1a3aa9 2260 }
1c6fdbd8 2261
67e0dd8f
KO		 2262 k = btree_path_level_peek(trans, iter->path,
2263 &iter->path->l[0], &iter->k);
3d495595
KO		 2264 if (!k.k ||
2265 ((iter->flags & BTREE_ITER_IS_EXTENTS)
e88a75eb
KO		 2266 ? bpos_ge(bkey_start_pos(k.k), search_key)
2267 : bpos_gt(k.k->p, search_key)))
67e0dd8f
KO		 2268 k = btree_path_level_prev(trans, iter->path,
2269 &iter->path->l[0], &iter->k);
ccf5a109 2270
e6e024e9 2271 if (likely(k.k)) {
c075ff70
KO		 2272 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS) {
2273 if (k.k->p.snapshot == iter->snapshot)
2274 goto got_key;
2275
2276 /*
2277 * If we have a saved candidate, and we're no
2278 * longer at the same _key_ (not pos), return
2279 * that candidate
2280 */
e88a75eb 2281 if (saved_path && !bkey_eq(k.k->p, saved_k.p)) {
7dcbdbd8 2282 bch2_path_put_nokeep(trans, iter->path,
c075ff70
KO		 2283 iter->flags & BTREE_ITER_INTENT);
2284 iter->path = saved_path;
2285 saved_path = NULL;
2286 iter->k = saved_k;
2287 k.v = saved_v;
2288 goto got_key;
2289 }
2290
2291 if (bch2_snapshot_is_ancestor(iter->trans->c,
2292 iter->snapshot,
2293 k.k->p.snapshot)) {
2294 if (saved_path)
7dcbdbd8 2295 bch2_path_put_nokeep(trans, saved_path,
c075ff70
KO		 2296 iter->flags & BTREE_ITER_INTENT);
2297 saved_path = btree_path_clone(trans, iter->path,
2298 iter->flags & BTREE_ITER_INTENT);
2299 saved_k = *k.k;
2300 saved_v = k.v;
2301 }
2302
2303 search_key = bpos_predecessor(k.k->p);
2304 continue;
2305 }
2306got_key:
2307 if (bkey_whiteout(k.k) &&
2308 !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS)) {
2309 search_key = bkey_predecessor(iter, k.k->p);
2310 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)
2311 search_key.snapshot = U32_MAX;
2312 continue;
2313 }
2314
1c6fdbd8 2315 break;
e88a75eb 2316 } else if (likely(!bpos_eq(iter->path->l[0].b->data->min_key, POS_MIN))) {
e6e024e9 2317 /* Advance to previous leaf node: */
67e0dd8f 2318 search_key = bpos_predecessor(iter->path->l[0].b->data->min_key);
e6e024e9
KO		 2319 } else {
2320 /* Start of btree: */
c8476a4e 2321 bch2_btree_iter_set_pos(iter, POS_MIN);
7e1a3aa9 2322 k = bkey_s_c_null;
fd211bc7 2323 goto out_no_locked;
7e1a3aa9 2324 }
ccf5a109 2325 }
1c6fdbd8 2326
e88a75eb 2327 EBUG_ON(bkey_gt(bkey_start_pos(k.k), iter->pos));
3d495595
KO		 2328
2329 /* Extents can straddle iter->pos: */
e88a75eb 2330 if (bkey_lt(k.k->p, iter->pos))
3d495595 2331 iter->pos = k.k->p;
c075ff70
KO		 2332
2333 if (iter->flags & BTREE_ITER_FILTER_SNAPSHOTS)
2334 iter->pos.snapshot = iter->snapshot;
fd211bc7
KO		 2335
2336 btree_path_set_should_be_locked(iter->path);
2337out_no_locked:
c075ff70 2338 if (saved_path)
7dcbdbd8 2339 bch2_path_put_nokeep(trans, saved_path, iter->flags & BTREE_ITER_INTENT);
67e0dd8f 2340
7e1a3aa9
KO		 2341 bch2_btree_iter_verify_entry_exit(iter);
2342 bch2_btree_iter_verify(iter);
67e0dd8f 2343
1c6fdbd8
KO		 2344 return k;
2345}
2346
ccf5a109 2347/**
96dea3d5 2348 * bch2_btree_iter_prev() - returns first key less than iterator's current
ccf5a109 2349 * position
96dea3d5
KO		 2350 * @iter: iterator to peek from
2351 *
2352 * Returns: key if found, or an error extractable with bkey_err().
ccf5a109
KO		 2353 */
2354struct bkey_s_c bch2_btree_iter_prev(struct btree_iter *iter)
2355{
e0ba3b64 2356 if (!bch2_btree_iter_rewind(iter))
2e70ce56 2357 return bkey_s_c_null;
ccf5a109 2358
2e70ce56 2359 return bch2_btree_iter_peek_prev(iter);
ccf5a109
KO		 2360}
2361
c3801239 2362struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *iter)
271a3d3a 2363{
9f6bd307 2364 struct btree_trans *trans = iter->trans;
953ee28a 2365 struct bpos search_key;
271a3d3a 2366 struct bkey_s_c k;
c3801239
KO		 2367 int ret;
2368
7e1a3aa9
KO		 2369 bch2_btree_iter_verify(iter);
2370 bch2_btree_iter_verify_entry_exit(iter);
2ae4573e 2371 EBUG_ON(iter->path->level && (iter->flags & BTREE_ITER_WITH_KEY_CACHE));
7e1a3aa9 2372
1d214eb1
KO		 2373 /* extents can't span inode numbers: */
2374 if ((iter->flags & BTREE_ITER_IS_EXTENTS) &&
953ee28a 2375 unlikely(iter->pos.offset == KEY_OFFSET_MAX)) {
1d214eb1
KO		 2376 if (iter->pos.inode == KEY_INODE_MAX)
2377 return bkey_s_c_null;
c3801239 2378
1d214eb1
KO		 2379 bch2_btree_iter_set_pos(iter, bpos_nosnap_successor(iter->pos));
2380 }
8042b5b7 2381
953ee28a 2382 search_key = btree_iter_search_key(iter);
ce91abd6 2383 iter->path = bch2_btree_path_set_pos(trans, iter->path, search_key,
ee2c6ea7
KO		 2384 iter->flags & BTREE_ITER_INTENT,
2385 btree_iter_ip_allocated(iter));
953ee28a 2386
67e0dd8f 2387 ret = bch2_btree_path_traverse(trans, iter->path, iter->flags);
23dfb3a2
KO		 2388 if (unlikely(ret)) {
2389 k = bkey_s_c_err(ret);
2390 goto out_no_locked;
2391 }
1c6fdbd8 2392
c075ff70
KO		 2393 if ((iter->flags & BTREE_ITER_CACHED) ||
2394 !(iter->flags & (BTREE_ITER_IS_EXTENTS|BTREE_ITER_FILTER_SNAPSHOTS))) {
953ee28a 2395 struct bkey_i *next_update;
1c6fdbd8 2396
5222a460 2397 if ((next_update = btree_trans_peek_updates(iter)) &&
e88a75eb 2398 bpos_eq(next_update->k.p, iter->pos)) {
1d214eb1
KO		 2399 iter->k = next_update->k;
2400 k = bkey_i_to_s_c(next_update);
5222a460 2401 goto out;
1d214eb1
KO		 2402 }
2403
5222a460
KO		 2404 if (unlikely(iter->flags & BTREE_ITER_WITH_JOURNAL) &&
2405 (k = btree_trans_peek_slot_journal(trans, iter)).k)
2406 goto out;
2407
f7b6ca23 2408 if (unlikely(iter->flags & BTREE_ITER_WITH_KEY_CACHE) &&
dcced069 2409 (k = btree_trans_peek_key_cache(iter, iter->pos)).k) {
8192f8a5 2410 if (!bkey_err(k))
f7b6ca23 2411 iter->k = *k.k;
8192f8a5
KO		 2412 /* We're not returning a key from iter->path: */
2413 goto out_no_locked;
f7b6ca23
KO		 2414 }
2415
5222a460 2416 k = bch2_btree_path_peek_slot(iter->path, &iter->k);
f42238b5
KO		 2417 if (unlikely(!k.k))
2418 goto out_no_locked;
1d214eb1
KO		 2419 } else {
2420 struct bpos next;
c72f687a
KO		 2421 struct bpos end = iter->pos;
2422
2423 if (iter->flags & BTREE_ITER_IS_EXTENTS)
2424 end.offset = U64_MAX;
1d214eb1 2425
2ae4573e
KO		 2426 EBUG_ON(iter->path->level);
2427
b1d87f52 2428 if (iter->flags & BTREE_ITER_INTENT) {
67e0dd8f 2429 struct btree_iter iter2;
b1d87f52 2430
67e0dd8f 2431 bch2_trans_copy_iter(&iter2, iter);
85d8cf16 2432 k = bch2_btree_iter_peek_upto(&iter2, end);
b1d87f52 2433
67e0dd8f
KO		 2434 if (k.k && !bkey_err(k)) {
2435 iter->k = iter2.k;
2436 k.k = &iter->k;
2437 }
2438 bch2_trans_iter_exit(trans, &iter2);
b1d87f52
KO		 2439 } else {
2440 struct bpos pos = iter->pos;
2441
c72f687a 2442 k = bch2_btree_iter_peek_upto(iter, end);
23dfb3a2
KO		 2443 if (unlikely(bkey_err(k)))
2444 bch2_btree_iter_set_pos(iter, pos);
2445 else
2446 iter->pos = pos;
b1d87f52 2447 }
1d214eb1
KO		 2448
2449 if (unlikely(bkey_err(k)))
f42238b5 2450 goto out_no_locked;
1d214eb1
KO		 2451
2452 next = k.k ? bkey_start_pos(k.k) : POS_MAX;
2453
e88a75eb 2454 if (bkey_lt(iter->pos, next)) {
1d214eb1
KO		 2455 bkey_init(&iter->k);
2456 iter->k.p = iter->pos;
c075ff70
KO		 2457
2458 if (iter->flags & BTREE_ITER_IS_EXTENTS) {
2459 bch2_key_resize(&iter->k,
2460 min_t(u64, KEY_SIZE_MAX,
2461 (next.inode == iter->pos.inode
2462 ? next.offset
2463 : KEY_OFFSET_MAX) -
2464 iter->pos.offset));
2465 EBUG_ON(!iter->k.size);
2466 }
1d214eb1
KO		 2467
2468 k = (struct bkey_s_c) { &iter->k, NULL };
1d214eb1 2469 }
271a3d3a 2470 }
5222a460 2471out:
fd211bc7
KO		 2472 btree_path_set_should_be_locked(iter->path);
2473out_no_locked:
7e1a3aa9
KO		 2474 bch2_btree_iter_verify_entry_exit(iter);
2475 bch2_btree_iter_verify(iter);
c075ff70
KO		 2476 ret = bch2_btree_iter_verify_ret(iter, k);
2477 if (unlikely(ret))
2478 return bkey_s_c_err(ret);
66a0a497 2479
63f1a598 2480 return k;
1c6fdbd8
KO		 2481}
2482
1c6fdbd8
KO		 2483struct bkey_s_c bch2_btree_iter_next_slot(struct btree_iter *iter)
2484{
e0ba3b64 2485 if (!bch2_btree_iter_advance(iter))
2e70ce56 2486 return bkey_s_c_null;
1c6fdbd8 2487
2dac0eae 2488 return bch2_btree_iter_peek_slot(iter);
1c6fdbd8
KO		 2489}
2490
18fc6ae5
KO		 2491struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_iter *iter)
2492{
e0ba3b64 2493 if (!bch2_btree_iter_rewind(iter))
18fc6ae5
KO		 2494 return bkey_s_c_null;
2495
2496 return bch2_btree_iter_peek_slot(iter);
2497}
2498
0f2ea655
KO		 2499struct bkey_s_c bch2_btree_iter_peek_and_restart_outlined(struct btree_iter *iter)
2500{
2501 struct bkey_s_c k;
2502
2503 while (btree_trans_too_many_iters(iter->trans) ||
2504 (k = bch2_btree_iter_peek_type(iter, iter->flags),
2505 bch2_err_matches(bkey_err(k), BCH_ERR_transaction_restart)))
2506 bch2_trans_begin(iter->trans);
2507
2508 return k;
2509}
2510
1c6fdbd8
KO		 2511/* new transactional stuff: */
2512
0423fb71
KO		 2513#ifdef CONFIG_BCACHEFS_DEBUG
2514static void btree_trans_verify_sorted_refs(struct btree_trans *trans)
2515{
67e0dd8f 2516 struct btree_path *path;
0423fb71
KO		 2517 unsigned i;
2518
f8fd5871 2519 BUG_ON(trans->nr_sorted != bitmap_weight(trans->paths_allocated, BTREE_ITER_MAX) - 1);
0423fb71 2520
67e0dd8f
KO		 2521 trans_for_each_path(trans, path) {
2522 BUG_ON(path->sorted_idx >= trans->nr_sorted);
2523 BUG_ON(trans->sorted[path->sorted_idx] != path->idx);
0423fb71
KO		 2524 }
2525
2526 for (i = 0; i < trans->nr_sorted; i++) {
2527 unsigned idx = trans->sorted[i];
2528
6e92d155 2529 BUG_ON(!test_bit(idx, trans->paths_allocated));
67e0dd8f 2530 BUG_ON(trans->paths[idx].sorted_idx != i);
0423fb71
KO		 2531 }
2532}
0423fb71
KO		 2533
2534static void btree_trans_verify_sorted(struct btree_trans *trans)
2535{
67e0dd8f 2536 struct btree_path *path, *prev = NULL;
0423fb71
KO		 2537 unsigned i;
2538
ee4d17d0
KO		 2539 if (!bch2_debug_check_iterators)
2540 return;
2541
67e0dd8f 2542 trans_for_each_path_inorder(trans, path, i) {
eb7bd15f 2543 if (prev && btree_path_cmp(prev, path) > 0) {
5c0bb66a 2544 __bch2_dump_trans_paths_updates(trans, true);
eb7bd15f
KO		 2545 panic("trans paths out of order!\n");
2546 }
67e0dd8f 2547 prev = path;
0423fb71 2548 }
0423fb71 2549}
068bcaa5
KO		 2550#else
2551static inline void btree_trans_verify_sorted_refs(struct btree_trans *trans) {}
2552static inline void btree_trans_verify_sorted(struct btree_trans *trans) {}
2553#endif
0423fb71 2554
068bcaa5 2555void __bch2_btree_trans_sort_paths(struct btree_trans *trans)
0423fb71
KO		 2556{
2557 int i, l = 0, r = trans->nr_sorted, inc = 1;
2558 bool swapped;
2559
068bcaa5
KO		 2560 btree_trans_verify_sorted_refs(trans);
2561
2562 if (trans->paths_sorted)
2563 goto out;
2564
0423fb71
KO		 2565 /*
2566 * Cocktail shaker sort: this is efficient because iterators will be
5c0bb66a 2567 * mostly sorted.
0423fb71
KO		 2568 */
2569 do {
2570 swapped = false;
2571
2572 for (i = inc > 0 ? l : r - 2;
2573 i + 1 < r && i >= l;
2574 i += inc) {
67e0dd8f
KO		 2575 if (btree_path_cmp(trans->paths + trans->sorted[i],
2576 trans->paths + trans->sorted[i + 1]) > 0) {
0423fb71 2577 swap(trans->sorted[i], trans->sorted[i + 1]);
67e0dd8f
KO		 2578 trans->paths[trans->sorted[i]].sorted_idx = i;
2579 trans->paths[trans->sorted[i + 1]].sorted_idx = i + 1;
0423fb71
KO		 2580 swapped = true;
2581 }
2582 }
2583
2584 if (inc > 0)
2585 --r;
2586 else
2587 l++;
2588 inc = -inc;
2589 } while (swapped);
2590
67e0dd8f 2591 trans->paths_sorted = true;
068bcaa5 2592out:
0423fb71
KO		 2593 btree_trans_verify_sorted(trans);
2594}
2595
67e0dd8f
KO		 2596static inline void btree_path_list_remove(struct btree_trans *trans,
2597 struct btree_path *path)
0423fb71
KO		 2598{
2599 unsigned i;
2600
67e0dd8f 2601 EBUG_ON(path->sorted_idx >= trans->nr_sorted);
0423fb71
KO		 2602#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2603 trans->nr_sorted--;
67e0dd8f
KO		 2604 memmove_u64s_down_small(trans->sorted + path->sorted_idx,
2605 trans->sorted + path->sorted_idx + 1,
2606 DIV_ROUND_UP(trans->nr_sorted - path->sorted_idx, 8));
0423fb71 2607#else
67e0dd8f 2608 array_remove_item(trans->sorted, trans->nr_sorted, path->sorted_idx);
0423fb71 2609#endif
67e0dd8f
KO		 2610 for (i = path->sorted_idx; i < trans->nr_sorted; i++)
2611 trans->paths[trans->sorted[i]].sorted_idx = i;
0423fb71 2612
67e0dd8f 2613 path->sorted_idx = U8_MAX;
0423fb71
KO		 2614}
2615
67e0dd8f
KO		 2616static inline void btree_path_list_add(struct btree_trans *trans,
2617 struct btree_path *pos,
2618 struct btree_path *path)
0423fb71
KO		 2619{
2620 unsigned i;
2621
068bcaa5 2622 path->sorted_idx = pos ? pos->sorted_idx + 1 : trans->nr_sorted;
0423fb71
KO		 2623
2624#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
67e0dd8f
KO		 2625 memmove_u64s_up_small(trans->sorted + path->sorted_idx + 1,
2626 trans->sorted + path->sorted_idx,
2627 DIV_ROUND_UP(trans->nr_sorted - path->sorted_idx, 8));
0423fb71 2628 trans->nr_sorted++;
67e0dd8f 2629 trans->sorted[path->sorted_idx] = path->idx;
0423fb71 2630#else
67e0dd8f 2631 array_insert_item(trans->sorted, trans->nr_sorted, path->sorted_idx, path->idx);
0423fb71
KO		 2632#endif
2633
67e0dd8f
KO		 2634 for (i = path->sorted_idx; i < trans->nr_sorted; i++)
2635 trans->paths[trans->sorted[i]].sorted_idx = i;
64bc0011 2636
0423fb71 2637 btree_trans_verify_sorted_refs(trans);
7c26ecae
KO		 2638}
2639
67e0dd8f 2640void bch2_trans_iter_exit(struct btree_trans *trans, struct btree_iter *iter)
64bc0011 2641{
1f2d9192 2642 if (iter->update_path)
7dcbdbd8 2643 bch2_path_put_nokeep(trans, iter->update_path,
1f2d9192 2644 iter->flags & BTREE_ITER_INTENT);
11f11737
KO		 2645 if (iter->path)
2646 bch2_path_put(trans, iter->path,
2647 iter->flags & BTREE_ITER_INTENT);
f7b6ca23
KO		 2648 if (iter->key_cache_path)
2649 bch2_path_put(trans, iter->key_cache_path,
2650 iter->flags & BTREE_ITER_INTENT);
67e0dd8f 2651 iter->path = NULL;
1f2d9192 2652 iter->update_path = NULL;
f7b6ca23 2653 iter->key_cache_path = NULL;
64bc0011
KO		 2654}
2655
c96f108b
KO		 2656void bch2_trans_iter_init_outlined(struct btree_trans *trans,
2657 struct btree_iter *iter,
2658 enum btree_id btree_id, struct bpos pos,
2659 unsigned flags)
2660{
2661 bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0,
ee2c6ea7
KO		 2662 bch2_btree_iter_flags(trans, btree_id, flags),
2663 _RET_IP_);
424eb881
KO		 2664}
2665
67e0dd8f
KO		 2666void bch2_trans_node_iter_init(struct btree_trans *trans,
2667 struct btree_iter *iter,
2668 enum btree_id btree_id,
2669 struct bpos pos,
2670 unsigned locks_want,
2671 unsigned depth,
2672 unsigned flags)
1c6fdbd8 2673{
1e81f89b
KO		 2674 flags |= BTREE_ITER_NOT_EXTENTS;
2675 flags |= __BTREE_ITER_ALL_SNAPSHOTS;
2676 flags |= BTREE_ITER_ALL_SNAPSHOTS;
c96f108b
KO		 2677
2678 bch2_trans_iter_init_common(trans, iter, btree_id, pos, locks_want, depth,
ee2c6ea7
KO		 2679 __bch2_btree_iter_flags(trans, btree_id, flags),
2680 _RET_IP_);
c96f108b
KO		 2681
2682 iter->min_depth = depth;
2683
67e0dd8f
KO		 2684 BUG_ON(iter->path->locks_want < min(locks_want, BTREE_MAX_DEPTH));
2685 BUG_ON(iter->path->level != depth);
2686 BUG_ON(iter->min_depth != depth);
2687}
7c26ecae 2688
67e0dd8f
KO		 2689void bch2_trans_copy_iter(struct btree_iter *dst, struct btree_iter *src)
2690{
2691 *dst = *src;
2692 if (src->path)
2693 __btree_path_get(src->path, src->flags & BTREE_ITER_INTENT);
1f2d9192
KO		 2694 if (src->update_path)
2695 __btree_path_get(src->update_path, src->flags & BTREE_ITER_INTENT);
f7b6ca23 2696 dst->key_cache_path = NULL;
1c6fdbd8
KO		 2697}
2698
14d8f26a 2699void *__bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
1c6fdbd8 2700{
616928c3 2701 unsigned new_top = trans->mem_top + size;
14d8f26a
KO		 2702 size_t old_bytes = trans->mem_bytes;
2703 size_t new_bytes = roundup_pow_of_two(new_top);
78367aaa 2704 int ret;
14d8f26a 2705 void *new_mem;
73a117d2
KO		 2706 void *p;
2707
616928c3
KO		 2708 trans->mem_max = max(trans->mem_max, new_top);
2709
14d8f26a 2710 WARN_ON_ONCE(new_bytes > BTREE_TRANS_MEM_MAX);
e131b6aa 2711
78367aaa
KO		 2712 new_mem = krealloc(trans->mem, new_bytes, GFP_NOWAIT|__GFP_NOWARN);
2713 if (unlikely(!new_mem)) {
2714 bch2_trans_unlock(trans);
2715
2716 new_mem = krealloc(trans->mem, new_bytes, GFP_KERNEL);
2717 if (!new_mem && new_bytes <= BTREE_TRANS_MEM_MAX) {
2718 new_mem = mempool_alloc(&trans->c->btree_trans_mem_pool, GFP_KERNEL);
2719 new_bytes = BTREE_TRANS_MEM_MAX;
2720 kfree(trans->mem);
2721 }
1c6fdbd8 2722
78367aaa
KO		 2723 if (!new_mem)
2724 return ERR_PTR(-BCH_ERR_ENOMEM_trans_kmalloc);
2725
2726 trans->mem = new_mem;
2727 trans->mem_bytes = new_bytes;
2728
2729 ret = bch2_trans_relock(trans);
2730 if (ret)
2731 return ERR_PTR(ret);
2732 }
1c6fdbd8 2733
14d8f26a
KO		 2734 trans->mem = new_mem;
2735 trans->mem_bytes = new_bytes;
1c6fdbd8 2736
14d8f26a
KO		 2737 if (old_bytes) {
2738 trace_and_count(trans->c, trans_restart_mem_realloced, trans, _RET_IP_, new_bytes);
2739 return ERR_PTR(btree_trans_restart(trans, BCH_ERR_transaction_restart_mem_realloced));
1c6fdbd8
KO		 2740 }
2741
20bceecb 2742 p = trans->mem + trans->mem_top;
1c6fdbd8 2743 trans->mem_top += size;
7ed158f2 2744 memset(p, 0, size);
20bceecb 2745 return p;
1c6fdbd8
KO		 2746}
2747
f82755e4
KO		 2748static inline void check_srcu_held_too_long(struct btree_trans *trans)
2749{
2750 WARN(trans->srcu_held && time_after(jiffies, trans->srcu_lock_time + HZ * 10),
2751 "btree trans held srcu lock (delaying memory reclaim) for %lu seconds",
2752 (jiffies - trans->srcu_lock_time) / HZ);
2753}
2754
c4accde4 2755void bch2_trans_srcu_unlock(struct btree_trans *trans)
e242b92a 2756{
c4accde4
KO		 2757 if (trans->srcu_held) {
2758 struct bch_fs *c = trans->c;
2759 struct btree_path *path;
e242b92a 2760
c4accde4
KO		 2761 trans_for_each_path(trans, path)
2762 if (path->cached && !btree_node_locked(path, 0))
2763 path->l[0].b = ERR_PTR(-BCH_ERR_no_btree_node_srcu_reset);
e242b92a 2764
f82755e4 2765 check_srcu_held_too_long(trans);
c4accde4
KO		 2766 srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
2767 trans->srcu_held = false;
2768 }
2769}
2770
2771void bch2_trans_srcu_lock(struct btree_trans *trans)
2772{
2773 if (!trans->srcu_held) {
2774 trans->srcu_idx = srcu_read_lock(&trans->c->btree_trans_barrier);
2775 trans->srcu_lock_time = jiffies;
2776 trans->srcu_held = true;
2777 }
e242b92a
KO		 2778}
2779
d38494c4 2780/**
955af634 2781 * bch2_trans_begin() - reset a transaction after a interrupted attempt
d38494c4 2782 * @trans: transaction to reset
d38494c4 2783 *
96dea3d5
KO		 2784 * Returns: current restart counter, to be used with trans_was_restarted()
2785 *
549d173c
KO		 2786 * While iterating over nodes or updating nodes a attempt to lock a btree node
2787 * may return BCH_ERR_transaction_restart when the trylock fails. When this
2788 * occurs bch2_trans_begin() should be called and the transaction retried.
d38494c4 2789 */
e941ae7d 2790u32 bch2_trans_begin(struct btree_trans *trans)
1c6fdbd8 2791{
67e0dd8f 2792 struct btree_path *path;
f375d6ca 2793 u64 now;
a8e00bd4 2794
0fbf71f8 2795 bch2_trans_reset_updates(trans);
1c6fdbd8 2796
c497df8b 2797 trans->restart_count++;
163e885a 2798 trans->mem_top = 0;
24de63da 2799 trans->journal_entries = NULL;
bf7b87a4 2800
67e0dd8f 2801 trans_for_each_path(trans, path) {
25a77231
KO		 2802 path->should_be_locked = false;
2803
e1f7fa06
KO		 2804 /*
2805 * If the transaction wasn't restarted, we're presuming to be
2806 * doing something new: dont keep iterators excpt the ones that
2807 * are in use - except for the subvolumes btree:
2808 */
2809 if (!trans->restarted && path->btree_id != BTREE_ID_subvolumes)
2810 path->preserve = false;
2811
67e0dd8f
KO		 2812 /*
2813 * XXX: we probably shouldn't be doing this if the transaction
2814 * was restarted, but currently we still overflow transaction
2815 * iterators if we do that
2816 */
2817 if (!path->ref && !path->preserve)
2818 __bch2_path_free(trans, path);
2819 else
25a77231 2820 path->preserve = false;
67e0dd8f
KO		 2821 }
2822
f375d6ca 2823 now = local_clock();
43de721a
KO		 2824 if (!trans->restarted &&
2825 (need_resched() ||
f375d6ca 2826 now - trans->last_begin_time > BTREE_TRANS_MAX_LOCK_HOLD_TIME_NS)) {
49c7cd9d 2827 drop_locks_do(trans, (cond_resched(), 0));
f375d6ca 2828 now = local_clock();
43de721a 2829 }
f375d6ca 2830 trans->last_begin_time = now;
50dc0f69 2831
c4accde4
KO		 2832 if (unlikely(trans->srcu_held &&
2833 time_after(jiffies, trans->srcu_lock_time + msecs_to_jiffies(10))))
2834 bch2_trans_srcu_unlock(trans);
e242b92a 2835
5e2d8be8 2836 trans->last_begin_ip = _RET_IP_;
60b55388 2837 if (trans->restarted) {
67e0dd8f 2838 bch2_btree_path_traverse_all(trans);
60b55388
KO		 2839 trans->notrace_relock_fail = false;
2840 }
e5af273f 2841
e941ae7d
KO		 2842 return trans->restart_count;
2843}
2844
6bd68ec2 2845static struct btree_trans *bch2_trans_alloc(struct bch_fs *c)
1a21bf98 2846{
6bd68ec2 2847 struct btree_trans *trans;
1a21bf98 2848
6bd68ec2
KO		 2849 if (IS_ENABLED(__KERNEL__)) {
2850 trans = this_cpu_xchg(c->btree_trans_bufs->trans, NULL);
2851 if (trans)
2852 return trans;
ff5b741c 2853 }
1a21bf98 2854
6bd68ec2
KO		 2855 trans = mempool_alloc(&c->btree_trans_pool, GFP_NOFS);
2856 /*
2857 * paths need to be zeroed, bch2_check_for_deadlock looks at
2858 * paths in other threads
2859 */
2860 memset(&trans->paths, 0, sizeof(trans->paths));
2861 return trans;
1a21bf98
KO		 2862}
2863
307e3c13
KO		 2864const char *bch2_btree_transaction_fns[BCH_TRANSACTIONS_NR];
2865
2866unsigned bch2_trans_get_fn_idx(const char *fn)
4aba7d45
KO		 2867{
2868 unsigned i;
2869
307e3c13
KO		 2870 for (i = 0; i < ARRAY_SIZE(bch2_btree_transaction_fns); i++)
2871 if (!bch2_btree_transaction_fns[i] ||
2872 bch2_btree_transaction_fns[i] == fn) {
2873 bch2_btree_transaction_fns[i] = fn;
4aba7d45
KO		 2874 return i;
2875 }
2876
2877 pr_warn_once("BCH_TRANSACTIONS_NR not big enough!");
2878 return i;
2879}
2880
6bd68ec2 2881struct btree_trans *__bch2_trans_get(struct bch_fs *c, unsigned fn_idx)
c0ebe3e4 2882 __acquires(&c->btree_trans_barrier)
1c6fdbd8 2883{
6bd68ec2 2884 struct btree_trans *trans;
5c0bb66a
KO		 2885 struct btree_transaction_stats *s;
2886
6bd68ec2
KO		 2887 trans = bch2_trans_alloc(c);
2888
ae1ede58 2889 memset(trans, 0, sizeof(*trans));
1c6fdbd8 2890 trans->c = c;
307e3c13
KO		 2891 trans->fn = fn_idx < ARRAY_SIZE(bch2_btree_transaction_fns)
2892 ? bch2_btree_transaction_fns[fn_idx] : NULL;
d7e4e513 2893 trans->last_begin_time = local_clock();
307e3c13 2894 trans->fn_idx = fn_idx;
33bd5d06 2895 trans->locking_wait.task = current;
5222a460 2896 trans->journal_replay_not_finished =
8a443d3e
KO		 2897 unlikely(!test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags)) &&
2898 atomic_inc_not_zero(&c->journal_keys.ref);
33bd5d06 2899 closure_init_stack(&trans->ref);
20bceecb 2900
f8fd5871
KO		 2901 trans->paths_allocated[0] = 1;
2902
616928c3 2903 s = btree_trans_stats(trans);
1f69368c 2904 if (s && s->max_mem) {
616928c3
KO		 2905 unsigned expected_mem_bytes = roundup_pow_of_two(s->max_mem);
2906
0b5c9f59 2907 trans->mem = kmalloc(expected_mem_bytes, GFP_KERNEL);
e131b6aa
KO		 2908
2909 if (!unlikely(trans->mem)) {
2910 trans->mem = mempool_alloc(&c->btree_trans_mem_pool, GFP_KERNEL);
2911 trans->mem_bytes = BTREE_TRANS_MEM_MAX;
2912 } else {
0b5c9f59 2913 trans->mem_bytes = expected_mem_bytes;
e131b6aa 2914 }
616928c3 2915 }
920e69bc
KO		 2916
2917 if (s) {
1f69368c 2918 trans->nr_max_paths = s->nr_max_paths;
24de63da 2919 trans->journal_entries_size = s->journal_entries_size;
920e69bc 2920 }
5c0bb66a 2921
c4accde4 2922 trans->srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
e242b92a 2923 trans->srcu_lock_time = jiffies;
c4accde4 2924 trans->srcu_held = true;
876c7af3 2925
b84d42c3 2926 if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG_TRANSACTIONS)) {
50b13bee
KO		 2927 struct btree_trans *pos;
2928
a5b696ee 2929 seqmutex_lock(&c->btree_trans_lock);
50b13bee 2930 list_for_each_entry(pos, &c->btree_trans_list, list) {
6623c0fc
KO		 2931 /*
2932 * We'd much prefer to be stricter here and completely
2933 * disallow multiple btree_trans in the same thread -
2934 * but the data move path calls bch2_write when we
2935 * already have a btree_trans initialized.
2936 */
2937 BUG_ON(trans->locking_wait.task->pid == pos->locking_wait.task->pid &&
2938 bch2_trans_locked(pos));
2939
33bd5d06 2940 if (trans->locking_wait.task->pid < pos->locking_wait.task->pid) {
50b13bee
KO		 2941 list_add_tail(&trans->list, &pos->list);
2942 goto list_add_done;
2943 }
2944 }
2945 list_add_tail(&trans->list, &c->btree_trans_list);
2946list_add_done:
a5b696ee 2947 seqmutex_unlock(&c->btree_trans_lock);
b84d42c3 2948 }
6bd68ec2
KO		 2949
2950 return trans;
1c6fdbd8
KO		 2951}
2952
67e0dd8f
KO		 2953static void check_btree_paths_leaked(struct btree_trans *trans)
2954{
2955#ifdef CONFIG_BCACHEFS_DEBUG
2956 struct bch_fs *c = trans->c;
2957 struct btree_path *path;
2958
2959 trans_for_each_path(trans, path)
2960 if (path->ref)
2961 goto leaked;
2962 return;
2963leaked:
669f87a5 2964 bch_err(c, "btree paths leaked from %s!", trans->fn);
67e0dd8f
KO		 2965 trans_for_each_path(trans, path)
2966 if (path->ref)
2967 printk(KERN_ERR " btree %s %pS\n",
88dfe193 2968 bch2_btree_id_str(path->btree_id),
67e0dd8f
KO		 2969 (void *) path->ip_allocated);
2970 /* Be noisy about this: */
2971 bch2_fatal_error(c);
2972#endif
2973}
2974
6bd68ec2 2975void bch2_trans_put(struct btree_trans *trans)
c0ebe3e4 2976 __releases(&c->btree_trans_barrier)
1c6fdbd8 2977{
67e0dd8f 2978 struct btree_insert_entry *i;
1a21bf98 2979 struct bch_fs *c = trans->c;
616928c3 2980 struct btree_transaction_stats *s = btree_trans_stats(trans);
1a21bf98 2981
ece254b2 2982 bch2_trans_unlock(trans);
1c6fdbd8 2983
a5b696ee
KO		 2984 if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG_TRANSACTIONS)) {
2985 seqmutex_lock(&c->btree_trans_lock);
2986 list_del(&trans->list);
2987 seqmutex_unlock(&c->btree_trans_lock);
2988 }
2989
33bd5d06
KO		 2990 closure_sync(&trans->ref);
2991
616928c3
KO		 2992 if (s)
2993 s->max_mem = max(s->max_mem, trans->mem_max);
2994
67e0dd8f
KO		 2995 trans_for_each_update(trans, i)
2996 __btree_path_put(i->path, true);
2997 trans->nr_updates = 0;
509d3e0a 2998
67e0dd8f 2999 check_btree_paths_leaked(trans);
50dc0f69 3000
f82755e4
KO		 3001 if (trans->srcu_held) {
3002 check_srcu_held_too_long(trans);
c4accde4 3003 srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
f82755e4 3004 }
876c7af3 3005
9620c3ec
KO		 3006 if (trans->fs_usage_deltas) {
3007 if (trans->fs_usage_deltas->size + sizeof(trans->fs_usage_deltas) ==
3008 REPLICAS_DELTA_LIST_MAX)
3009 mempool_free(trans->fs_usage_deltas,
67e0dd8f 3010 &c->replicas_delta_pool);
9620c3ec
KO		 3011 else
3012 kfree(trans->fs_usage_deltas);
3013 }
e131b6aa 3014
8a443d3e
KO		 3015 if (unlikely(trans->journal_replay_not_finished))
3016 bch2_journal_keys_put(c);
3017
e131b6aa 3018 if (trans->mem_bytes == BTREE_TRANS_MEM_MAX)
67e0dd8f 3019 mempool_free(trans->mem, &c->btree_trans_mem_pool);
e131b6aa
KO		 3020 else
3021 kfree(trans->mem);
1a21bf98 3022
6bd68ec2
KO		 3023 /* Userspace doesn't have a real percpu implementation: */
3024 if (IS_ENABLED(__KERNEL__))
3025 trans = this_cpu_xchg(c->btree_trans_bufs->trans, trans);
3026 if (trans)
3027 mempool_free(trans, &c->btree_trans_pool);
1c6fdbd8 3028}
36e9d698 3029
b3d1e6ca 3030static void __maybe_unused
afbc7194
KO		 3031bch2_btree_bkey_cached_common_to_text(struct printbuf *out,
3032 struct btree_bkey_cached_common *b)
d211b408 3033{
c240c3a9
KO		 3034 struct six_lock_count c = six_lock_counts(&b->lock);
3035 struct task_struct *owner;
3036 pid_t pid;
3037
3038 rcu_read_lock();
3039 owner = READ_ONCE(b->lock.owner);
3e3e02e6 3040 pid = owner ? owner->pid : 0;
c240c3a9
KO		 3041 rcu_read_unlock();
3042
afbc7194
KO		 3043 prt_tab(out);
3044 prt_printf(out, "%px %c l=%u %s:", b, b->cached ? 'c' : 'b',
88dfe193 3045 b->level, bch2_btree_id_str(b->btree_id));
4e6defd1 3046 bch2_bpos_to_text(out, btree_node_pos(b));
c240c3a9 3047
afbc7194
KO		 3048 prt_tab(out);
3049 prt_printf(out, " locks %u:%u:%u held by pid %u",
c240c3a9 3050 c.n[0], c.n[1], c.n[2], pid);
d211b408
KO		 3051}
3052
50b13bee 3053void bch2_btree_trans_to_text(struct printbuf *out, struct btree_trans *trans)
5c1d808a 3054{
67e0dd8f 3055 struct btree_path *path;
86b74451 3056 struct btree_bkey_cached_common *b;
c7ce2732 3057 static char lock_types[] = { 'r', 'i', 'w' };
33981244 3058 struct task_struct *task = READ_ONCE(trans->locking_wait.task);
f154c3eb 3059 unsigned l, idx;
495aabed 3060
afbc7194
KO		 3061 if (!out->nr_tabstops) {
3062 printbuf_tabstop_push(out, 16);
3063 printbuf_tabstop_push(out, 32);
3064 }
3065
33981244 3066 prt_printf(out, "%i %s\n", task ? task->pid : 0, trans->fn);
495aabed 3067
f154c3eb 3068 trans_for_each_path_safe(trans, path, idx) {
50b13bee
KO		 3069 if (!path->nodes_locked)
3070 continue;
495aabed 3071
50b13bee
KO		 3072 prt_printf(out, " path %u %c l=%u %s:",
3073 path->idx,
3074 path->cached ? 'c' : 'b',
3075 path->level,
88dfe193 3076 bch2_btree_id_str(path->btree_id));
50b13bee 3077 bch2_bpos_to_text(out, path->pos);
afbc7194 3078 prt_newline(out);
50b13bee
KO		 3079
3080 for (l = 0; l < BTREE_MAX_DEPTH; l++) {
86b74451 3081 if (btree_node_locked(path, l) &&
315c9ba6 3082 !IS_ERR_OR_NULL(b = (void *) READ_ONCE(path->l[l].b))) {
d4263e56
KO		 3083 prt_printf(out, " %c l=%u ",
3084 lock_types[btree_node_locked_type(path, l)], l);
afbc7194
KO		 3085 bch2_btree_bkey_cached_common_to_text(out, b);
3086 prt_newline(out);
495aabed
KO		 3087 }
3088 }
50b13bee 3089 }
495aabed 3090
50b13bee
KO		 3091 b = READ_ONCE(trans->locking);
3092 if (b) {
9d7f2a41
KO		 3093 prt_printf(out, " blocked for %lluus on",
3094 div_u64(local_clock() - trans->locking_wait.start_time,
3095 1000));
afbc7194
KO		 3096 prt_newline(out);
3097 prt_printf(out, " %c", lock_types[trans->locking_wait.lock_want]);
3098 bch2_btree_bkey_cached_common_to_text(out, b);
3099 prt_newline(out);
495aabed 3100 }
495aabed
KO		 3101}
3102
36e9d698
KO		 3103void bch2_fs_btree_iter_exit(struct bch_fs *c)
3104{
4aba7d45 3105 struct btree_transaction_stats *s;
6bd68ec2
KO		 3106 struct btree_trans *trans;
3107 int cpu;
3108
3109 trans = list_first_entry_or_null(&c->btree_trans_list, struct btree_trans, list);
3110 if (trans)
3111 panic("%s leaked btree_trans\n", trans->fn);
3112
3113 if (c->btree_trans_bufs)
3114 for_each_possible_cpu(cpu)
3115 kfree(per_cpu_ptr(c->btree_trans_bufs, cpu)->trans);
3116 free_percpu(c->btree_trans_bufs);
4aba7d45
KO		 3117
3118 for (s = c->btree_transaction_stats;
3119 s < c->btree_transaction_stats + ARRAY_SIZE(c->btree_transaction_stats);
5c0bb66a
KO		 3120 s++) {
3121 kfree(s->max_paths_text);
4aba7d45 3122 bch2_time_stats_exit(&s->lock_hold_times);
5c0bb66a 3123 }
4aba7d45 3124
99fafb04
KO		 3125 if (c->btree_trans_barrier_initialized)
3126 cleanup_srcu_struct(&c->btree_trans_barrier);
e131b6aa 3127 mempool_exit(&c->btree_trans_mem_pool);
6bd68ec2 3128 mempool_exit(&c->btree_trans_pool);
36e9d698
KO		 3129}
3130
50a8a732 3131void bch2_fs_btree_iter_init_early(struct bch_fs *c)
36e9d698 3132{
4aba7d45 3133 struct btree_transaction_stats *s;
36e9d698 3134
4aba7d45
KO		 3135 for (s = c->btree_transaction_stats;
3136 s < c->btree_transaction_stats + ARRAY_SIZE(c->btree_transaction_stats);
5c0bb66a 3137 s++) {
4aba7d45 3138 bch2_time_stats_init(&s->lock_hold_times);
5c0bb66a
KO		 3139 mutex_init(&s->lock);
3140 }
4aba7d45 3141
495aabed 3142 INIT_LIST_HEAD(&c->btree_trans_list);
a5b696ee 3143 seqmutex_init(&c->btree_trans_lock);
50a8a732
TB		 3144}
3145
3146int bch2_fs_btree_iter_init(struct bch_fs *c)
3147{
3148 int ret;
495aabed 3149
6bd68ec2
KO		 3150 c->btree_trans_bufs = alloc_percpu(struct btree_trans_buf);
3151 if (!c->btree_trans_bufs)
3152 return -ENOMEM;
3153
3154 ret = mempool_init_kmalloc_pool(&c->btree_trans_pool, 1,
3155 sizeof(struct btree_trans)) ?:
e131b6aa 3156 mempool_init_kmalloc_pool(&c->btree_trans_mem_pool, 1,
99fafb04
KO		 3157 BTREE_TRANS_MEM_MAX) ?:
3158 init_srcu_struct(&c->btree_trans_barrier);
3159 if (!ret)
3160 c->btree_trans_barrier_initialized = true;
3161 return ret;
36e9d698 3162}
Linux 6.x block layer and io_uring tree(s)