1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2010 Kent Overstreet <kent.overstreet@gmail.com> 4 * Copyright (C) 2014 Datera Inc. 5 */ 6 7 #include "bcachefs.h" 8 #include "alloc_background.h" 9 #include "alloc_foreground.h" 10 #include "backpointers.h" 11 #include "bkey_methods.h" 12 #include "bkey_buf.h" 13 #include "btree_journal_iter.h" 14 #include "btree_key_cache.h" 15 #include "btree_locking.h" 16 #include "btree_node_scan.h" 17 #include "btree_update_interior.h" 18 #include "btree_io.h" 19 #include "btree_gc.h" 20 #include "buckets.h" 21 #include "clock.h" 22 #include "debug.h" 23 #include "disk_accounting.h" 24 #include "ec.h" 25 #include "error.h" 26 #include "extents.h" 27 #include "journal.h" 28 #include "keylist.h" 29 #include "move.h" 30 #include "recovery_passes.h" 31 #include "reflink.h" 32 #include "replicas.h" 33 #include "super-io.h" 34 #include "trace.h" 35 36 #include <linux/slab.h> 37 #include <linux/bitops.h> 38 #include <linux/freezer.h> 39 #include <linux/kthread.h> 40 #include <linux/preempt.h> 41 #include <linux/rcupdate.h> 42 #include <linux/sched/task.h> 43 44 #define DROP_THIS_NODE 10 45 #define DROP_PREV_NODE 11 46 #define DID_FILL_FROM_SCAN 12 47 48 static const char * const bch2_gc_phase_strs[] = { 49 #define x(n) #n, 50 GC_PHASES() 51 #undef x 52 NULL 53 }; 54 55 void bch2_gc_pos_to_text(struct printbuf *out, struct gc_pos *p) 56 { 57 prt_str(out, bch2_gc_phase_strs[p->phase]); 58 prt_char(out, ' '); 59 bch2_btree_id_to_text(out, p->btree); 60 prt_printf(out, " l=%u ", p->level); 61 bch2_bpos_to_text(out, p->pos); 62 } 63 64 static struct bkey_s unsafe_bkey_s_c_to_s(struct bkey_s_c k) 65 { 66 return (struct bkey_s) {{{ 67 (struct bkey *) k.k, 68 (struct bch_val *) k.v 69 }}}; 70 } 71 72 static inline void __gc_pos_set(struct bch_fs *c, struct gc_pos new_pos) 73 { 74 preempt_disable(); 75 write_seqcount_begin(&c->gc_pos_lock); 76 c->gc_pos = new_pos; 77 write_seqcount_end(&c->gc_pos_lock); 78 preempt_enable(); 79 } 80 81 static inline void gc_pos_set(struct bch_fs *c, struct gc_pos new_pos) 82 { 83 BUG_ON(gc_pos_cmp(new_pos, c->gc_pos) < 0); 84 __gc_pos_set(c, new_pos); 85 } 86 87 static void btree_ptr_to_v2(struct btree *b, struct bkey_i_btree_ptr_v2 *dst) 88 { 89 switch (b->key.k.type) { 90 case KEY_TYPE_btree_ptr: { 91 struct bkey_i_btree_ptr *src = bkey_i_to_btree_ptr(&b->key); 92 93 dst->k.p = src->k.p; 94 dst->v.mem_ptr = 0; 95 dst->v.seq = b->data->keys.seq; 96 dst->v.sectors_written = 0; 97 dst->v.flags = 0; 98 dst->v.min_key = b->data->min_key; 99 set_bkey_val_bytes(&dst->k, sizeof(dst->v) + bkey_val_bytes(&src->k)); 100 memcpy(dst->v.start, src->v.start, bkey_val_bytes(&src->k)); 101 break; 102 } 103 case KEY_TYPE_btree_ptr_v2: 104 bkey_copy(&dst->k_i, &b->key); 105 break; 106 default: 107 BUG(); 108 } 109 } 110 111 static int set_node_min(struct bch_fs *c, struct btree *b, struct bpos new_min) 112 { 113 struct bkey_i_btree_ptr_v2 *new; 114 int ret; 115 116 if (c->opts.verbose) { 117 struct printbuf buf = PRINTBUF; 118 119 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key)); 120 prt_str(&buf, " -> "); 121 bch2_bpos_to_text(&buf, new_min); 122 123 bch_info(c, "%s(): %s", __func__, buf.buf); 124 printbuf_exit(&buf); 125 } 126 127 new = kmalloc_array(BKEY_BTREE_PTR_U64s_MAX, sizeof(u64), GFP_KERNEL); 128 if (!new) 129 return -BCH_ERR_ENOMEM_gc_repair_key; 130 131 btree_ptr_to_v2(b, new); 132 b->data->min_key = new_min; 133 new->v.min_key = new_min; 134 SET_BTREE_PTR_RANGE_UPDATED(&new->v, true); 135 136 ret = bch2_journal_key_insert_take(c, b->c.btree_id, b->c.level + 1, &new->k_i); 137 if (ret) { 138 kfree(new); 139 return ret; 140 } 141 142 bch2_btree_node_drop_keys_outside_node(b); 143 bkey_copy(&b->key, &new->k_i); 144 return 0; 145 } 146 147 static int set_node_max(struct bch_fs *c, struct btree *b, struct bpos new_max) 148 { 149 struct bkey_i_btree_ptr_v2 *new; 150 int ret; 151 152 if (c->opts.verbose) { 153 struct printbuf buf = PRINTBUF; 154 155 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key)); 156 prt_str(&buf, " -> "); 157 bch2_bpos_to_text(&buf, new_max); 158 159 bch_info(c, "%s(): %s", __func__, buf.buf); 160 printbuf_exit(&buf); 161 } 162 163 ret = bch2_journal_key_delete(c, b->c.btree_id, b->c.level + 1, b->key.k.p); 164 if (ret) 165 return ret; 166 167 new = kmalloc_array(BKEY_BTREE_PTR_U64s_MAX, sizeof(u64), GFP_KERNEL); 168 if (!new) 169 return -BCH_ERR_ENOMEM_gc_repair_key; 170 171 btree_ptr_to_v2(b, new); 172 b->data->max_key = new_max; 173 new->k.p = new_max; 174 SET_BTREE_PTR_RANGE_UPDATED(&new->v, true); 175 176 ret = bch2_journal_key_insert_take(c, b->c.btree_id, b->c.level + 1, &new->k_i); 177 if (ret) { 178 kfree(new); 179 return ret; 180 } 181 182 bch2_btree_node_drop_keys_outside_node(b); 183 184 mutex_lock(&c->btree_cache.lock); 185 bch2_btree_node_hash_remove(&c->btree_cache, b); 186 187 bkey_copy(&b->key, &new->k_i); 188 ret = __bch2_btree_node_hash_insert(&c->btree_cache, b); 189 BUG_ON(ret); 190 mutex_unlock(&c->btree_cache.lock); 191 return 0; 192 } 193 194 static int btree_check_node_boundaries(struct btree_trans *trans, struct btree *b, 195 struct btree *prev, struct btree *cur, 196 struct bpos *pulled_from_scan) 197 { 198 struct bch_fs *c = trans->c; 199 struct bpos expected_start = !prev 200 ? b->data->min_key 201 : bpos_successor(prev->key.k.p); 202 struct printbuf buf = PRINTBUF; 203 int ret = 0; 204 205 BUG_ON(b->key.k.type == KEY_TYPE_btree_ptr_v2 && 206 !bpos_eq(bkey_i_to_btree_ptr_v2(&b->key)->v.min_key, 207 b->data->min_key)); 208 209 if (bpos_eq(expected_start, cur->data->min_key)) 210 return 0; 211 212 prt_printf(&buf, " at btree %s level %u:\n parent: ", 213 bch2_btree_id_str(b->c.btree_id), b->c.level); 214 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key)); 215 216 if (prev) { 217 prt_printf(&buf, "\n prev: "); 218 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&prev->key)); 219 } 220 221 prt_str(&buf, "\n next: "); 222 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&cur->key)); 223 224 if (bpos_lt(expected_start, cur->data->min_key)) { /* gap */ 225 if (b->c.level == 1 && 226 bpos_lt(*pulled_from_scan, cur->data->min_key)) { 227 ret = bch2_get_scanned_nodes(c, b->c.btree_id, 0, 228 expected_start, 229 bpos_predecessor(cur->data->min_key)); 230 if (ret) 231 goto err; 232 233 *pulled_from_scan = cur->data->min_key; 234 ret = DID_FILL_FROM_SCAN; 235 } else { 236 if (mustfix_fsck_err(trans, btree_node_topology_bad_min_key, 237 "btree node with incorrect min_key%s", buf.buf)) 238 ret = set_node_min(c, cur, expected_start); 239 } 240 } else { /* overlap */ 241 if (prev && BTREE_NODE_SEQ(cur->data) > BTREE_NODE_SEQ(prev->data)) { /* cur overwrites prev */ 242 if (bpos_ge(prev->data->min_key, cur->data->min_key)) { /* fully? */ 243 if (mustfix_fsck_err(trans, btree_node_topology_overwritten_by_next_node, 244 "btree node overwritten by next node%s", buf.buf)) 245 ret = DROP_PREV_NODE; 246 } else { 247 if (mustfix_fsck_err(trans, btree_node_topology_bad_max_key, 248 "btree node with incorrect max_key%s", buf.buf)) 249 ret = set_node_max(c, prev, 250 bpos_predecessor(cur->data->min_key)); 251 } 252 } else { 253 if (bpos_ge(expected_start, cur->data->max_key)) { /* fully? */ 254 if (mustfix_fsck_err(trans, btree_node_topology_overwritten_by_prev_node, 255 "btree node overwritten by prev node%s", buf.buf)) 256 ret = DROP_THIS_NODE; 257 } else { 258 if (mustfix_fsck_err(trans, btree_node_topology_bad_min_key, 259 "btree node with incorrect min_key%s", buf.buf)) 260 ret = set_node_min(c, cur, expected_start); 261 } 262 } 263 } 264 err: 265 fsck_err: 266 printbuf_exit(&buf); 267 return ret; 268 } 269 270 static int btree_repair_node_end(struct btree_trans *trans, struct btree *b, 271 struct btree *child, struct bpos *pulled_from_scan) 272 { 273 struct bch_fs *c = trans->c; 274 struct printbuf buf = PRINTBUF; 275 int ret = 0; 276 277 if (bpos_eq(child->key.k.p, b->key.k.p)) 278 return 0; 279 280 prt_printf(&buf, "at btree %s level %u:\n parent: ", 281 bch2_btree_id_str(b->c.btree_id), b->c.level); 282 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key)); 283 284 prt_str(&buf, "\n child: "); 285 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&child->key)); 286 287 if (mustfix_fsck_err(trans, btree_node_topology_bad_max_key, 288 "btree node with incorrect max_key%s", buf.buf)) { 289 if (b->c.level == 1 && 290 bpos_lt(*pulled_from_scan, b->key.k.p)) { 291 ret = bch2_get_scanned_nodes(c, b->c.btree_id, 0, 292 bpos_successor(child->key.k.p), b->key.k.p); 293 if (ret) 294 goto err; 295 296 *pulled_from_scan = b->key.k.p; 297 ret = DID_FILL_FROM_SCAN; 298 } else { 299 ret = set_node_max(c, child, b->key.k.p); 300 } 301 } 302 err: 303 fsck_err: 304 printbuf_exit(&buf); 305 return ret; 306 } 307 308 static int bch2_btree_repair_topology_recurse(struct btree_trans *trans, struct btree *b, 309 struct bpos *pulled_from_scan) 310 { 311 struct bch_fs *c = trans->c; 312 struct btree_and_journal_iter iter; 313 struct bkey_s_c k; 314 struct bkey_buf prev_k, cur_k; 315 struct btree *prev = NULL, *cur = NULL; 316 bool have_child, new_pass = false; 317 struct printbuf buf = PRINTBUF; 318 int ret = 0; 319 320 if (!b->c.level) 321 return 0; 322 323 bch2_bkey_buf_init(&prev_k); 324 bch2_bkey_buf_init(&cur_k); 325 again: 326 cur = prev = NULL; 327 have_child = new_pass = false; 328 bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b); 329 iter.prefetch = true; 330 331 while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) { 332 BUG_ON(bpos_lt(k.k->p, b->data->min_key)); 333 BUG_ON(bpos_gt(k.k->p, b->data->max_key)); 334 335 bch2_btree_and_journal_iter_advance(&iter); 336 bch2_bkey_buf_reassemble(&cur_k, c, k); 337 338 cur = bch2_btree_node_get_noiter(trans, cur_k.k, 339 b->c.btree_id, b->c.level - 1, 340 false); 341 ret = PTR_ERR_OR_ZERO(cur); 342 343 printbuf_reset(&buf); 344 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(cur_k.k)); 345 346 if (mustfix_fsck_err_on(bch2_err_matches(ret, EIO), 347 trans, btree_node_unreadable, 348 "Topology repair: unreadable btree node at btree %s level %u:\n" 349 " %s", 350 bch2_btree_id_str(b->c.btree_id), 351 b->c.level - 1, 352 buf.buf)) { 353 bch2_btree_node_evict(trans, cur_k.k); 354 cur = NULL; 355 ret = bch2_journal_key_delete(c, b->c.btree_id, 356 b->c.level, cur_k.k->k.p); 357 if (ret) 358 break; 359 360 if (!btree_id_is_alloc(b->c.btree_id)) { 361 ret = bch2_run_explicit_recovery_pass(c, BCH_RECOVERY_PASS_scan_for_btree_nodes); 362 if (ret) 363 break; 364 } 365 continue; 366 } 367 368 bch_err_msg(c, ret, "getting btree node"); 369 if (ret) 370 break; 371 372 if (bch2_btree_node_is_stale(c, cur)) { 373 bch_info(c, "btree node %s older than nodes found by scanning", buf.buf); 374 six_unlock_read(&cur->c.lock); 375 bch2_btree_node_evict(trans, cur_k.k); 376 ret = bch2_journal_key_delete(c, b->c.btree_id, 377 b->c.level, cur_k.k->k.p); 378 cur = NULL; 379 if (ret) 380 break; 381 continue; 382 } 383 384 ret = btree_check_node_boundaries(trans, b, prev, cur, pulled_from_scan); 385 if (ret == DID_FILL_FROM_SCAN) { 386 new_pass = true; 387 ret = 0; 388 } 389 390 if (ret == DROP_THIS_NODE) { 391 six_unlock_read(&cur->c.lock); 392 bch2_btree_node_evict(trans, cur_k.k); 393 ret = bch2_journal_key_delete(c, b->c.btree_id, 394 b->c.level, cur_k.k->k.p); 395 cur = NULL; 396 if (ret) 397 break; 398 continue; 399 } 400 401 if (prev) 402 six_unlock_read(&prev->c.lock); 403 prev = NULL; 404 405 if (ret == DROP_PREV_NODE) { 406 bch_info(c, "dropped prev node"); 407 bch2_btree_node_evict(trans, prev_k.k); 408 ret = bch2_journal_key_delete(c, b->c.btree_id, 409 b->c.level, prev_k.k->k.p); 410 if (ret) 411 break; 412 413 bch2_btree_and_journal_iter_exit(&iter); 414 goto again; 415 } else if (ret) 416 break; 417 418 prev = cur; 419 cur = NULL; 420 bch2_bkey_buf_copy(&prev_k, c, cur_k.k); 421 } 422 423 if (!ret && !IS_ERR_OR_NULL(prev)) { 424 BUG_ON(cur); 425 ret = btree_repair_node_end(trans, b, prev, pulled_from_scan); 426 if (ret == DID_FILL_FROM_SCAN) { 427 new_pass = true; 428 ret = 0; 429 } 430 } 431 432 if (!IS_ERR_OR_NULL(prev)) 433 six_unlock_read(&prev->c.lock); 434 prev = NULL; 435 if (!IS_ERR_OR_NULL(cur)) 436 six_unlock_read(&cur->c.lock); 437 cur = NULL; 438 439 if (ret) 440 goto err; 441 442 bch2_btree_and_journal_iter_exit(&iter); 443 444 if (new_pass) 445 goto again; 446 447 bch2_btree_and_journal_iter_init_node_iter(trans, &iter, b); 448 iter.prefetch = true; 449 450 while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) { 451 bch2_bkey_buf_reassemble(&cur_k, c, k); 452 bch2_btree_and_journal_iter_advance(&iter); 453 454 cur = bch2_btree_node_get_noiter(trans, cur_k.k, 455 b->c.btree_id, b->c.level - 1, 456 false); 457 ret = PTR_ERR_OR_ZERO(cur); 458 459 bch_err_msg(c, ret, "getting btree node"); 460 if (ret) 461 goto err; 462 463 ret = bch2_btree_repair_topology_recurse(trans, cur, pulled_from_scan); 464 six_unlock_read(&cur->c.lock); 465 cur = NULL; 466 467 if (ret == DROP_THIS_NODE) { 468 bch2_btree_node_evict(trans, cur_k.k); 469 ret = bch2_journal_key_delete(c, b->c.btree_id, 470 b->c.level, cur_k.k->k.p); 471 new_pass = true; 472 } 473 474 if (ret) 475 goto err; 476 477 have_child = true; 478 } 479 480 printbuf_reset(&buf); 481 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key)); 482 483 if (mustfix_fsck_err_on(!have_child, 484 trans, btree_node_topology_interior_node_empty, 485 "empty interior btree node at btree %s level %u\n" 486 " %s", 487 bch2_btree_id_str(b->c.btree_id), 488 b->c.level, buf.buf)) 489 ret = DROP_THIS_NODE; 490 err: 491 fsck_err: 492 if (!IS_ERR_OR_NULL(prev)) 493 six_unlock_read(&prev->c.lock); 494 if (!IS_ERR_OR_NULL(cur)) 495 six_unlock_read(&cur->c.lock); 496 497 bch2_btree_and_journal_iter_exit(&iter); 498 499 if (!ret && new_pass) 500 goto again; 501 502 BUG_ON(!ret && bch2_btree_node_check_topology(trans, b)); 503 504 bch2_bkey_buf_exit(&prev_k, c); 505 bch2_bkey_buf_exit(&cur_k, c); 506 printbuf_exit(&buf); 507 return ret; 508 } 509 510 int bch2_check_topology(struct bch_fs *c) 511 { 512 struct btree_trans *trans = bch2_trans_get(c); 513 struct bpos pulled_from_scan = POS_MIN; 514 int ret = 0; 515 516 bch2_trans_srcu_unlock(trans); 517 518 for (unsigned i = 0; i < btree_id_nr_alive(c) && !ret; i++) { 519 struct btree_root *r = bch2_btree_id_root(c, i); 520 bool reconstructed_root = false; 521 522 if (r->error) { 523 ret = bch2_run_explicit_recovery_pass(c, BCH_RECOVERY_PASS_scan_for_btree_nodes); 524 if (ret) 525 break; 526 reconstruct_root: 527 bch_info(c, "btree root %s unreadable, must recover from scan", bch2_btree_id_str(i)); 528 529 r->alive = false; 530 r->error = 0; 531 532 if (!bch2_btree_has_scanned_nodes(c, i)) { 533 mustfix_fsck_err(trans, btree_root_unreadable_and_scan_found_nothing, 534 "no nodes found for btree %s, continue?", bch2_btree_id_str(i)); 535 bch2_btree_root_alloc_fake_trans(trans, i, 0); 536 } else { 537 bch2_btree_root_alloc_fake_trans(trans, i, 1); 538 bch2_shoot_down_journal_keys(c, i, 1, BTREE_MAX_DEPTH, POS_MIN, SPOS_MAX); 539 ret = bch2_get_scanned_nodes(c, i, 0, POS_MIN, SPOS_MAX); 540 if (ret) 541 break; 542 } 543 544 reconstructed_root = true; 545 } 546 547 struct btree *b = r->b; 548 549 btree_node_lock_nopath_nofail(trans, &b->c, SIX_LOCK_read); 550 ret = bch2_btree_repair_topology_recurse(trans, b, &pulled_from_scan); 551 six_unlock_read(&b->c.lock); 552 553 if (ret == DROP_THIS_NODE) { 554 mutex_lock(&c->btree_cache.lock); 555 bch2_btree_node_hash_remove(&c->btree_cache, b); 556 mutex_unlock(&c->btree_cache.lock); 557 558 r->b = NULL; 559 560 if (!reconstructed_root) 561 goto reconstruct_root; 562 563 bch_err(c, "empty btree root %s", bch2_btree_id_str(i)); 564 bch2_btree_root_alloc_fake_trans(trans, i, 0); 565 r->alive = false; 566 ret = 0; 567 } 568 } 569 fsck_err: 570 bch2_trans_put(trans); 571 return ret; 572 } 573 574 /* marking of btree keys/nodes: */ 575 576 static int bch2_gc_mark_key(struct btree_trans *trans, enum btree_id btree_id, 577 unsigned level, struct btree **prev, 578 struct btree_iter *iter, struct bkey_s_c k, 579 bool initial) 580 { 581 struct bch_fs *c = trans->c; 582 583 if (iter) { 584 struct btree_path *path = btree_iter_path(trans, iter); 585 struct btree *b = path_l(path)->b; 586 587 if (*prev != b) { 588 int ret = bch2_btree_node_check_topology(trans, b); 589 if (ret) 590 return ret; 591 } 592 *prev = b; 593 } 594 595 struct bkey deleted = KEY(0, 0, 0); 596 struct bkey_s_c old = (struct bkey_s_c) { &deleted, NULL }; 597 struct printbuf buf = PRINTBUF; 598 int ret = 0; 599 600 deleted.p = k.k->p; 601 602 if (initial) { 603 BUG_ON(bch2_journal_seq_verify && 604 k.k->bversion.lo > atomic64_read(&c->journal.seq)); 605 606 if (fsck_err_on(btree_id != BTREE_ID_accounting && 607 k.k->bversion.lo > atomic64_read(&c->key_version), 608 trans, bkey_version_in_future, 609 "key version number higher than recorded %llu\n %s", 610 atomic64_read(&c->key_version), 611 (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) 612 atomic64_set(&c->key_version, k.k->bversion.lo); 613 } 614 615 if (mustfix_fsck_err_on(level && !bch2_dev_btree_bitmap_marked(c, k), 616 trans, btree_bitmap_not_marked, 617 "btree ptr not marked in member info btree allocated bitmap\n %s", 618 (printbuf_reset(&buf), 619 bch2_bkey_val_to_text(&buf, c, k), 620 buf.buf))) { 621 mutex_lock(&c->sb_lock); 622 bch2_dev_btree_bitmap_mark(c, k); 623 bch2_write_super(c); 624 mutex_unlock(&c->sb_lock); 625 } 626 627 /* 628 * We require a commit before key_trigger() because 629 * key_trigger(BTREE_TRIGGER_GC) is not idempotant; we'll calculate the 630 * wrong result if we run it multiple times. 631 */ 632 unsigned flags = !iter ? BTREE_TRIGGER_is_root : 0; 633 634 ret = bch2_key_trigger(trans, btree_id, level, old, unsafe_bkey_s_c_to_s(k), 635 BTREE_TRIGGER_check_repair|flags); 636 if (ret) 637 goto out; 638 639 if (trans->nr_updates) { 640 ret = bch2_trans_commit(trans, NULL, NULL, 0) ?: 641 -BCH_ERR_transaction_restart_nested; 642 goto out; 643 } 644 645 ret = bch2_key_trigger(trans, btree_id, level, old, unsafe_bkey_s_c_to_s(k), 646 BTREE_TRIGGER_gc|BTREE_TRIGGER_insert|flags); 647 out: 648 fsck_err: 649 printbuf_exit(&buf); 650 bch_err_fn(c, ret); 651 return ret; 652 } 653 654 static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree, bool initial) 655 { 656 struct bch_fs *c = trans->c; 657 unsigned target_depth = btree_node_type_has_triggers(__btree_node_type(0, btree)) ? 0 : 1; 658 int ret = 0; 659 660 /* We need to make sure every leaf node is readable before going RW */ 661 if (initial) 662 target_depth = 0; 663 664 for (unsigned level = target_depth; level < BTREE_MAX_DEPTH; level++) { 665 struct btree *prev = NULL; 666 struct btree_iter iter; 667 bch2_trans_node_iter_init(trans, &iter, btree, POS_MIN, 0, level, 668 BTREE_ITER_prefetch); 669 670 ret = for_each_btree_key_continue(trans, iter, 0, k, ({ 671 gc_pos_set(c, gc_pos_btree(btree, level, k.k->p)); 672 bch2_gc_mark_key(trans, btree, level, &prev, &iter, k, initial); 673 })); 674 if (ret) 675 goto err; 676 } 677 678 /* root */ 679 do { 680 retry_root: 681 bch2_trans_begin(trans); 682 683 struct btree_iter iter; 684 bch2_trans_node_iter_init(trans, &iter, btree, POS_MIN, 685 0, bch2_btree_id_root(c, btree)->b->c.level, 0); 686 struct btree *b = bch2_btree_iter_peek_node(&iter); 687 ret = PTR_ERR_OR_ZERO(b); 688 if (ret) 689 goto err_root; 690 691 if (b != btree_node_root(c, b)) { 692 bch2_trans_iter_exit(trans, &iter); 693 goto retry_root; 694 } 695 696 gc_pos_set(c, gc_pos_btree(btree, b->c.level + 1, SPOS_MAX)); 697 struct bkey_s_c k = bkey_i_to_s_c(&b->key); 698 ret = bch2_gc_mark_key(trans, btree, b->c.level + 1, NULL, NULL, k, initial); 699 err_root: 700 bch2_trans_iter_exit(trans, &iter); 701 } while (bch2_err_matches(ret, BCH_ERR_transaction_restart)); 702 err: 703 bch_err_fn(c, ret); 704 return ret; 705 } 706 707 static inline int btree_id_gc_phase_cmp(enum btree_id l, enum btree_id r) 708 { 709 return cmp_int(gc_btree_order(l), gc_btree_order(r)); 710 } 711 712 static int bch2_gc_btrees(struct bch_fs *c) 713 { 714 struct btree_trans *trans = bch2_trans_get(c); 715 enum btree_id ids[BTREE_ID_NR]; 716 unsigned i; 717 int ret = 0; 718 719 for (i = 0; i < BTREE_ID_NR; i++) 720 ids[i] = i; 721 bubble_sort(ids, BTREE_ID_NR, btree_id_gc_phase_cmp); 722 723 for (i = 0; i < btree_id_nr_alive(c) && !ret; i++) { 724 unsigned btree = i < BTREE_ID_NR ? ids[i] : i; 725 726 if (IS_ERR_OR_NULL(bch2_btree_id_root(c, btree)->b)) 727 continue; 728 729 ret = bch2_gc_btree(trans, btree, true); 730 731 if (mustfix_fsck_err_on(bch2_err_matches(ret, EIO), 732 trans, btree_node_read_error, 733 "btree node read error for %s", 734 bch2_btree_id_str(btree))) 735 ret = bch2_run_explicit_recovery_pass(c, BCH_RECOVERY_PASS_check_topology); 736 } 737 fsck_err: 738 bch2_trans_put(trans); 739 bch_err_fn(c, ret); 740 return ret; 741 } 742 743 static int bch2_mark_superblocks(struct bch_fs *c) 744 { 745 gc_pos_set(c, gc_phase(GC_PHASE_sb)); 746 747 return bch2_trans_mark_dev_sbs_flags(c, BTREE_TRIGGER_gc); 748 } 749 750 static void bch2_gc_free(struct bch_fs *c) 751 { 752 bch2_accounting_gc_free(c); 753 754 genradix_free(&c->reflink_gc_table); 755 genradix_free(&c->gc_stripes); 756 757 for_each_member_device(c, ca) 758 genradix_free(&ca->buckets_gc); 759 } 760 761 static int bch2_gc_start(struct bch_fs *c) 762 { 763 for_each_member_device(c, ca) { 764 int ret = bch2_dev_usage_init(ca, true); 765 if (ret) { 766 bch2_dev_put(ca); 767 return ret; 768 } 769 } 770 771 return 0; 772 } 773 774 /* returns true if not equal */ 775 static inline bool bch2_alloc_v4_cmp(struct bch_alloc_v4 l, 776 struct bch_alloc_v4 r) 777 { 778 return l.gen != r.gen || 779 l.oldest_gen != r.oldest_gen || 780 l.data_type != r.data_type || 781 l.dirty_sectors != r.dirty_sectors || 782 l.stripe_sectors != r.stripe_sectors || 783 l.cached_sectors != r.cached_sectors || 784 l.stripe_redundancy != r.stripe_redundancy || 785 l.stripe != r.stripe; 786 } 787 788 static int bch2_alloc_write_key(struct btree_trans *trans, 789 struct btree_iter *iter, 790 struct bch_dev *ca, 791 struct bkey_s_c k) 792 { 793 struct bch_fs *c = trans->c; 794 struct bkey_i_alloc_v4 *a; 795 struct bch_alloc_v4 old_gc, gc, old_convert, new; 796 const struct bch_alloc_v4 *old; 797 int ret; 798 799 if (!bucket_valid(ca, k.k->p.offset)) 800 return 0; 801 802 old = bch2_alloc_to_v4(k, &old_convert); 803 gc = new = *old; 804 805 percpu_down_read(&c->mark_lock); 806 __bucket_m_to_alloc(&gc, *gc_bucket(ca, iter->pos.offset)); 807 808 old_gc = gc; 809 810 if ((old->data_type == BCH_DATA_sb || 811 old->data_type == BCH_DATA_journal) && 812 !bch2_dev_is_online(ca)) { 813 gc.data_type = old->data_type; 814 gc.dirty_sectors = old->dirty_sectors; 815 } 816 percpu_up_read(&c->mark_lock); 817 818 /* 819 * gc.data_type doesn't yet include need_discard & need_gc_gen states - 820 * fix that here: 821 */ 822 alloc_data_type_set(&gc, gc.data_type); 823 824 if (gc.data_type != old_gc.data_type || 825 gc.dirty_sectors != old_gc.dirty_sectors) { 826 ret = bch2_alloc_key_to_dev_counters(trans, ca, &old_gc, &gc, BTREE_TRIGGER_gc); 827 if (ret) 828 return ret; 829 } 830 831 gc.fragmentation_lru = alloc_lru_idx_fragmentation(gc, ca); 832 833 if (fsck_err_on(new.data_type != gc.data_type, 834 trans, alloc_key_data_type_wrong, 835 "bucket %llu:%llu gen %u has wrong data_type" 836 ": got %s, should be %s", 837 iter->pos.inode, iter->pos.offset, 838 gc.gen, 839 bch2_data_type_str(new.data_type), 840 bch2_data_type_str(gc.data_type))) 841 new.data_type = gc.data_type; 842 843 #define copy_bucket_field(_errtype, _f) \ 844 if (fsck_err_on(new._f != gc._f, \ 845 trans, _errtype, \ 846 "bucket %llu:%llu gen %u data type %s has wrong " #_f \ 847 ": got %llu, should be %llu", \ 848 iter->pos.inode, iter->pos.offset, \ 849 gc.gen, \ 850 bch2_data_type_str(gc.data_type), \ 851 (u64) new._f, (u64) gc._f)) \ 852 new._f = gc._f; \ 853 854 copy_bucket_field(alloc_key_gen_wrong, gen); 855 copy_bucket_field(alloc_key_dirty_sectors_wrong, dirty_sectors); 856 copy_bucket_field(alloc_key_stripe_sectors_wrong, stripe_sectors); 857 copy_bucket_field(alloc_key_cached_sectors_wrong, cached_sectors); 858 copy_bucket_field(alloc_key_stripe_wrong, stripe); 859 copy_bucket_field(alloc_key_stripe_redundancy_wrong, stripe_redundancy); 860 copy_bucket_field(alloc_key_fragmentation_lru_wrong, fragmentation_lru); 861 #undef copy_bucket_field 862 863 if (!bch2_alloc_v4_cmp(*old, new)) 864 return 0; 865 866 a = bch2_alloc_to_v4_mut(trans, k); 867 ret = PTR_ERR_OR_ZERO(a); 868 if (ret) 869 return ret; 870 871 a->v = new; 872 873 /* 874 * The trigger normally makes sure these are set, but we're not running 875 * triggers: 876 */ 877 if (a->v.data_type == BCH_DATA_cached && !a->v.io_time[READ]) 878 a->v.io_time[READ] = max_t(u64, 1, atomic64_read(&c->io_clock[READ].now)); 879 880 ret = bch2_trans_update(trans, iter, &a->k_i, BTREE_TRIGGER_norun); 881 fsck_err: 882 return ret; 883 } 884 885 static int bch2_gc_alloc_done(struct bch_fs *c) 886 { 887 int ret = 0; 888 889 for_each_member_device(c, ca) { 890 ret = bch2_trans_run(c, 891 for_each_btree_key_upto_commit(trans, iter, BTREE_ID_alloc, 892 POS(ca->dev_idx, ca->mi.first_bucket), 893 POS(ca->dev_idx, ca->mi.nbuckets - 1), 894 BTREE_ITER_slots|BTREE_ITER_prefetch, k, 895 NULL, NULL, BCH_TRANS_COMMIT_lazy_rw, 896 bch2_alloc_write_key(trans, &iter, ca, k))); 897 if (ret) { 898 bch2_dev_put(ca); 899 break; 900 } 901 } 902 903 bch_err_fn(c, ret); 904 return ret; 905 } 906 907 static int bch2_gc_alloc_start(struct bch_fs *c) 908 { 909 int ret = 0; 910 911 for_each_member_device(c, ca) { 912 ret = genradix_prealloc(&ca->buckets_gc, ca->mi.nbuckets, GFP_KERNEL); 913 if (ret) { 914 bch2_dev_put(ca); 915 ret = -BCH_ERR_ENOMEM_gc_alloc_start; 916 break; 917 } 918 } 919 920 bch_err_fn(c, ret); 921 return ret; 922 } 923 924 static int bch2_gc_write_reflink_key(struct btree_trans *trans, 925 struct btree_iter *iter, 926 struct bkey_s_c k, 927 size_t *idx) 928 { 929 struct bch_fs *c = trans->c; 930 const __le64 *refcount = bkey_refcount_c(k); 931 struct printbuf buf = PRINTBUF; 932 struct reflink_gc *r; 933 int ret = 0; 934 935 if (!refcount) 936 return 0; 937 938 while ((r = genradix_ptr(&c->reflink_gc_table, *idx)) && 939 r->offset < k.k->p.offset) 940 ++*idx; 941 942 if (!r || 943 r->offset != k.k->p.offset || 944 r->size != k.k->size) { 945 bch_err(c, "unexpected inconsistency walking reflink table at gc finish"); 946 return -EINVAL; 947 } 948 949 if (fsck_err_on(r->refcount != le64_to_cpu(*refcount), 950 trans, reflink_v_refcount_wrong, 951 "reflink key has wrong refcount:\n" 952 " %s\n" 953 " should be %u", 954 (bch2_bkey_val_to_text(&buf, c, k), buf.buf), 955 r->refcount)) { 956 struct bkey_i *new = bch2_bkey_make_mut_noupdate(trans, k); 957 ret = PTR_ERR_OR_ZERO(new); 958 if (ret) 959 goto out; 960 961 if (!r->refcount) 962 new->k.type = KEY_TYPE_deleted; 963 else 964 *bkey_refcount(bkey_i_to_s(new)) = cpu_to_le64(r->refcount); 965 ret = bch2_trans_update(trans, iter, new, 0); 966 } 967 out: 968 fsck_err: 969 printbuf_exit(&buf); 970 return ret; 971 } 972 973 static int bch2_gc_reflink_done(struct bch_fs *c) 974 { 975 size_t idx = 0; 976 977 int ret = bch2_trans_run(c, 978 for_each_btree_key_commit(trans, iter, 979 BTREE_ID_reflink, POS_MIN, 980 BTREE_ITER_prefetch, k, 981 NULL, NULL, BCH_TRANS_COMMIT_no_enospc, 982 bch2_gc_write_reflink_key(trans, &iter, k, &idx))); 983 c->reflink_gc_nr = 0; 984 return ret; 985 } 986 987 static int bch2_gc_reflink_start(struct bch_fs *c) 988 { 989 c->reflink_gc_nr = 0; 990 991 int ret = bch2_trans_run(c, 992 for_each_btree_key(trans, iter, BTREE_ID_reflink, POS_MIN, 993 BTREE_ITER_prefetch, k, ({ 994 const __le64 *refcount = bkey_refcount_c(k); 995 996 if (!refcount) 997 continue; 998 999 struct reflink_gc *r = genradix_ptr_alloc(&c->reflink_gc_table, 1000 c->reflink_gc_nr++, GFP_KERNEL); 1001 if (!r) { 1002 ret = -BCH_ERR_ENOMEM_gc_reflink_start; 1003 break; 1004 } 1005 1006 r->offset = k.k->p.offset; 1007 r->size = k.k->size; 1008 r->refcount = 0; 1009 0; 1010 }))); 1011 1012 bch_err_fn(c, ret); 1013 return ret; 1014 } 1015 1016 static int bch2_gc_write_stripes_key(struct btree_trans *trans, 1017 struct btree_iter *iter, 1018 struct bkey_s_c k) 1019 { 1020 struct bch_fs *c = trans->c; 1021 struct printbuf buf = PRINTBUF; 1022 const struct bch_stripe *s; 1023 struct gc_stripe *m; 1024 bool bad = false; 1025 unsigned i; 1026 int ret = 0; 1027 1028 if (k.k->type != KEY_TYPE_stripe) 1029 return 0; 1030 1031 s = bkey_s_c_to_stripe(k).v; 1032 m = genradix_ptr(&c->gc_stripes, k.k->p.offset); 1033 1034 for (i = 0; i < s->nr_blocks; i++) { 1035 u32 old = stripe_blockcount_get(s, i); 1036 u32 new = (m ? m->block_sectors[i] : 0); 1037 1038 if (old != new) { 1039 prt_printf(&buf, "stripe block %u has wrong sector count: got %u, should be %u\n", 1040 i, old, new); 1041 bad = true; 1042 } 1043 } 1044 1045 if (bad) 1046 bch2_bkey_val_to_text(&buf, c, k); 1047 1048 if (fsck_err_on(bad, 1049 trans, stripe_sector_count_wrong, 1050 "%s", buf.buf)) { 1051 struct bkey_i_stripe *new; 1052 1053 new = bch2_trans_kmalloc(trans, bkey_bytes(k.k)); 1054 ret = PTR_ERR_OR_ZERO(new); 1055 if (ret) 1056 return ret; 1057 1058 bkey_reassemble(&new->k_i, k); 1059 1060 for (i = 0; i < new->v.nr_blocks; i++) 1061 stripe_blockcount_set(&new->v, i, m ? m->block_sectors[i] : 0); 1062 1063 ret = bch2_trans_update(trans, iter, &new->k_i, 0); 1064 } 1065 fsck_err: 1066 printbuf_exit(&buf); 1067 return ret; 1068 } 1069 1070 static int bch2_gc_stripes_done(struct bch_fs *c) 1071 { 1072 return bch2_trans_run(c, 1073 for_each_btree_key_commit(trans, iter, 1074 BTREE_ID_stripes, POS_MIN, 1075 BTREE_ITER_prefetch, k, 1076 NULL, NULL, BCH_TRANS_COMMIT_no_enospc, 1077 bch2_gc_write_stripes_key(trans, &iter, k))); 1078 } 1079 1080 /** 1081 * bch2_check_allocations - walk all references to buckets, and recompute them: 1082 * 1083 * @c: filesystem object 1084 * 1085 * Returns: 0 on success, or standard errcode on failure 1086 * 1087 * Order matters here: 1088 * - Concurrent GC relies on the fact that we have a total ordering for 1089 * everything that GC walks - see gc_will_visit_node(), 1090 * gc_will_visit_root() 1091 * 1092 * - also, references move around in the course of index updates and 1093 * various other crap: everything needs to agree on the ordering 1094 * references are allowed to move around in - e.g., we're allowed to 1095 * start with a reference owned by an open_bucket (the allocator) and 1096 * move it to the btree, but not the reverse. 1097 * 1098 * This is necessary to ensure that gc doesn't miss references that 1099 * move around - if references move backwards in the ordering GC 1100 * uses, GC could skip past them 1101 */ 1102 int bch2_check_allocations(struct bch_fs *c) 1103 { 1104 int ret; 1105 1106 lockdep_assert_held(&c->state_lock); 1107 1108 down_write(&c->gc_lock); 1109 1110 bch2_btree_interior_updates_flush(c); 1111 1112 ret = bch2_gc_accounting_start(c) ?: 1113 bch2_gc_start(c) ?: 1114 bch2_gc_alloc_start(c) ?: 1115 bch2_gc_reflink_start(c); 1116 if (ret) 1117 goto out; 1118 1119 gc_pos_set(c, gc_phase(GC_PHASE_start)); 1120 1121 ret = bch2_mark_superblocks(c); 1122 bch_err_msg(c, ret, "marking superblocks"); 1123 if (ret) 1124 goto out; 1125 1126 ret = bch2_gc_btrees(c); 1127 if (ret) 1128 goto out; 1129 1130 c->gc_count++; 1131 1132 ret = bch2_gc_alloc_done(c) ?: 1133 bch2_gc_accounting_done(c) ?: 1134 bch2_gc_stripes_done(c) ?: 1135 bch2_gc_reflink_done(c); 1136 out: 1137 percpu_down_write(&c->mark_lock); 1138 /* Indicates that gc is no longer in progress: */ 1139 __gc_pos_set(c, gc_phase(GC_PHASE_not_running)); 1140 1141 bch2_gc_free(c); 1142 percpu_up_write(&c->mark_lock); 1143 1144 up_write(&c->gc_lock); 1145 1146 /* 1147 * At startup, allocations can happen directly instead of via the 1148 * allocator thread - issue wakeup in case they blocked on gc_lock: 1149 */ 1150 closure_wake_up(&c->freelist_wait); 1151 bch_err_fn(c, ret); 1152 return ret; 1153 } 1154 1155 static int gc_btree_gens_key(struct btree_trans *trans, 1156 struct btree_iter *iter, 1157 struct bkey_s_c k) 1158 { 1159 struct bch_fs *c = trans->c; 1160 struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k); 1161 struct bkey_i *u; 1162 int ret; 1163 1164 if (unlikely(test_bit(BCH_FS_going_ro, &c->flags))) 1165 return -EROFS; 1166 1167 percpu_down_read(&c->mark_lock); 1168 rcu_read_lock(); 1169 bkey_for_each_ptr(ptrs, ptr) { 1170 struct bch_dev *ca = bch2_dev_rcu(c, ptr->dev); 1171 if (!ca) 1172 continue; 1173 1174 if (dev_ptr_stale(ca, ptr) > 16) { 1175 rcu_read_unlock(); 1176 percpu_up_read(&c->mark_lock); 1177 goto update; 1178 } 1179 } 1180 1181 bkey_for_each_ptr(ptrs, ptr) { 1182 struct bch_dev *ca = bch2_dev_rcu(c, ptr->dev); 1183 if (!ca) 1184 continue; 1185 1186 u8 *gen = &ca->oldest_gen[PTR_BUCKET_NR(ca, ptr)]; 1187 if (gen_after(*gen, ptr->gen)) 1188 *gen = ptr->gen; 1189 } 1190 rcu_read_unlock(); 1191 percpu_up_read(&c->mark_lock); 1192 return 0; 1193 update: 1194 u = bch2_bkey_make_mut(trans, iter, &k, 0); 1195 ret = PTR_ERR_OR_ZERO(u); 1196 if (ret) 1197 return ret; 1198 1199 bch2_extent_normalize(c, bkey_i_to_s(u)); 1200 return 0; 1201 } 1202 1203 static int bch2_alloc_write_oldest_gen(struct btree_trans *trans, struct bch_dev *ca, 1204 struct btree_iter *iter, struct bkey_s_c k) 1205 { 1206 struct bch_alloc_v4 a_convert; 1207 const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, &a_convert); 1208 struct bkey_i_alloc_v4 *a_mut; 1209 int ret; 1210 1211 if (a->oldest_gen == ca->oldest_gen[iter->pos.offset]) 1212 return 0; 1213 1214 a_mut = bch2_alloc_to_v4_mut(trans, k); 1215 ret = PTR_ERR_OR_ZERO(a_mut); 1216 if (ret) 1217 return ret; 1218 1219 a_mut->v.oldest_gen = ca->oldest_gen[iter->pos.offset]; 1220 alloc_data_type_set(&a_mut->v, a_mut->v.data_type); 1221 1222 return bch2_trans_update(trans, iter, &a_mut->k_i, 0); 1223 } 1224 1225 int bch2_gc_gens(struct bch_fs *c) 1226 { 1227 u64 b, start_time = local_clock(); 1228 int ret; 1229 1230 /* 1231 * Ideally we would be using state_lock and not gc_gens_lock here, but that 1232 * introduces a deadlock in the RO path - we currently take the state 1233 * lock at the start of going RO, thus the gc thread may get stuck: 1234 */ 1235 if (!mutex_trylock(&c->gc_gens_lock)) 1236 return 0; 1237 1238 trace_and_count(c, gc_gens_start, c); 1239 1240 down_read(&c->state_lock); 1241 1242 for_each_member_device(c, ca) { 1243 struct bucket_gens *gens = bucket_gens(ca); 1244 1245 BUG_ON(ca->oldest_gen); 1246 1247 ca->oldest_gen = kvmalloc(gens->nbuckets, GFP_KERNEL); 1248 if (!ca->oldest_gen) { 1249 bch2_dev_put(ca); 1250 ret = -BCH_ERR_ENOMEM_gc_gens; 1251 goto err; 1252 } 1253 1254 for (b = gens->first_bucket; 1255 b < gens->nbuckets; b++) 1256 ca->oldest_gen[b] = gens->b[b]; 1257 } 1258 1259 for (unsigned i = 0; i < BTREE_ID_NR; i++) 1260 if (btree_type_has_ptrs(i)) { 1261 c->gc_gens_btree = i; 1262 c->gc_gens_pos = POS_MIN; 1263 1264 ret = bch2_trans_run(c, 1265 for_each_btree_key_commit(trans, iter, i, 1266 POS_MIN, 1267 BTREE_ITER_prefetch|BTREE_ITER_all_snapshots, 1268 k, 1269 NULL, NULL, 1270 BCH_TRANS_COMMIT_no_enospc, 1271 gc_btree_gens_key(trans, &iter, k))); 1272 if (ret) 1273 goto err; 1274 } 1275 1276 struct bch_dev *ca = NULL; 1277 ret = bch2_trans_run(c, 1278 for_each_btree_key_commit(trans, iter, BTREE_ID_alloc, 1279 POS_MIN, 1280 BTREE_ITER_prefetch, 1281 k, 1282 NULL, NULL, 1283 BCH_TRANS_COMMIT_no_enospc, ({ 1284 ca = bch2_dev_iterate(c, ca, k.k->p.inode); 1285 if (!ca) { 1286 bch2_btree_iter_set_pos(&iter, POS(k.k->p.inode + 1, 0)); 1287 continue; 1288 } 1289 bch2_alloc_write_oldest_gen(trans, ca, &iter, k); 1290 }))); 1291 bch2_dev_put(ca); 1292 1293 if (ret) 1294 goto err; 1295 1296 c->gc_gens_btree = 0; 1297 c->gc_gens_pos = POS_MIN; 1298 1299 c->gc_count++; 1300 1301 bch2_time_stats_update(&c->times[BCH_TIME_btree_gc], start_time); 1302 trace_and_count(c, gc_gens_end, c); 1303 err: 1304 for_each_member_device(c, ca) { 1305 kvfree(ca->oldest_gen); 1306 ca->oldest_gen = NULL; 1307 } 1308 1309 up_read(&c->state_lock); 1310 mutex_unlock(&c->gc_gens_lock); 1311 if (!bch2_err_matches(ret, EROFS)) 1312 bch_err_fn(c, ret); 1313 return ret; 1314 } 1315 1316 static void bch2_gc_gens_work(struct work_struct *work) 1317 { 1318 struct bch_fs *c = container_of(work, struct bch_fs, gc_gens_work); 1319 bch2_gc_gens(c); 1320 bch2_write_ref_put(c, BCH_WRITE_REF_gc_gens); 1321 } 1322 1323 void bch2_gc_gens_async(struct bch_fs *c) 1324 { 1325 if (bch2_write_ref_tryget(c, BCH_WRITE_REF_gc_gens) && 1326 !queue_work(c->write_ref_wq, &c->gc_gens_work)) 1327 bch2_write_ref_put(c, BCH_WRITE_REF_gc_gens); 1328 } 1329 1330 void bch2_fs_gc_init(struct bch_fs *c) 1331 { 1332 seqcount_init(&c->gc_pos_lock); 1333 1334 INIT_WORK(&c->gc_gens_work, bch2_gc_gens_work); 1335 } 1336