1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Some low level IO code, and hacks for various block layer limitations 4 * 5 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com> 6 * Copyright 2012 Google, Inc. 7 */ 8 9 #include "bcachefs.h" 10 #include "alloc_background.h" 11 #include "alloc_foreground.h" 12 #include "btree_update.h" 13 #include "buckets.h" 14 #include "checksum.h" 15 #include "clock.h" 16 #include "compress.h" 17 #include "data_update.h" 18 #include "disk_groups.h" 19 #include "ec.h" 20 #include "error.h" 21 #include "io_read.h" 22 #include "io_misc.h" 23 #include "io_write.h" 24 #include "subvolume.h" 25 #include "trace.h" 26 27 #include <linux/sched/mm.h> 28 29 #ifndef CONFIG_BCACHEFS_NO_LATENCY_ACCT 30 31 static bool bch2_target_congested(struct bch_fs *c, u16 target) 32 { 33 const struct bch_devs_mask *devs; 34 unsigned d, nr = 0, total = 0; 35 u64 now = local_clock(), last; 36 s64 congested; 37 struct bch_dev *ca; 38 39 if (!target) 40 return false; 41 42 rcu_read_lock(); 43 devs = bch2_target_to_mask(c, target) ?: 44 &c->rw_devs[BCH_DATA_user]; 45 46 for_each_set_bit(d, devs->d, BCH_SB_MEMBERS_MAX) { 47 ca = rcu_dereference(c->devs[d]); 48 if (!ca) 49 continue; 50 51 congested = atomic_read(&ca->congested); 52 last = READ_ONCE(ca->congested_last); 53 if (time_after64(now, last)) 54 congested -= (now - last) >> 12; 55 56 total += max(congested, 0LL); 57 nr++; 58 } 59 rcu_read_unlock(); 60 61 return bch2_rand_range(nr * CONGESTED_MAX) < total; 62 } 63 64 #else 65 66 static bool bch2_target_congested(struct bch_fs *c, u16 target) 67 { 68 return false; 69 } 70 71 #endif 72 73 /* Cache promotion on read */ 74 75 struct promote_op { 76 struct rcu_head rcu; 77 u64 start_time; 78 79 struct rhash_head hash; 80 struct bpos pos; 81 82 struct data_update write; 83 struct bio_vec bi_inline_vecs[]; /* must be last */ 84 }; 85 86 static const struct rhashtable_params bch_promote_params = { 87 .head_offset = offsetof(struct promote_op, hash), 88 .key_offset = offsetof(struct promote_op, pos), 89 .key_len = sizeof(struct bpos), 90 .automatic_shrinking = true, 91 }; 92 93 static inline int should_promote(struct bch_fs *c, struct bkey_s_c k, 94 struct bpos pos, 95 struct bch_io_opts opts, 96 unsigned flags, 97 struct bch_io_failures *failed) 98 { 99 if (!failed) { 100 BUG_ON(!opts.promote_target); 101 102 if (!(flags & BCH_READ_MAY_PROMOTE)) 103 return -BCH_ERR_nopromote_may_not; 104 105 if (bch2_bkey_has_target(c, k, opts.promote_target)) 106 return -BCH_ERR_nopromote_already_promoted; 107 108 if (bkey_extent_is_unwritten(k)) 109 return -BCH_ERR_nopromote_unwritten; 110 111 if (bch2_target_congested(c, opts.promote_target)) 112 return -BCH_ERR_nopromote_congested; 113 } 114 115 if (rhashtable_lookup_fast(&c->promote_table, &pos, 116 bch_promote_params)) 117 return -BCH_ERR_nopromote_in_flight; 118 119 return 0; 120 } 121 122 static void promote_free(struct bch_fs *c, struct promote_op *op) 123 { 124 int ret; 125 126 bch2_data_update_exit(&op->write); 127 128 ret = rhashtable_remove_fast(&c->promote_table, &op->hash, 129 bch_promote_params); 130 BUG_ON(ret); 131 bch2_write_ref_put(c, BCH_WRITE_REF_promote); 132 kfree_rcu(op, rcu); 133 } 134 135 static void promote_done(struct bch_write_op *wop) 136 { 137 struct promote_op *op = 138 container_of(wop, struct promote_op, write.op); 139 struct bch_fs *c = op->write.op.c; 140 141 bch2_time_stats_update(&c->times[BCH_TIME_data_promote], 142 op->start_time); 143 promote_free(c, op); 144 } 145 146 static void promote_start(struct promote_op *op, struct bch_read_bio *rbio) 147 { 148 struct bio *bio = &op->write.op.wbio.bio; 149 150 trace_and_count(op->write.op.c, read_promote, &rbio->bio); 151 152 /* we now own pages: */ 153 BUG_ON(!rbio->bounce); 154 BUG_ON(rbio->bio.bi_vcnt > bio->bi_max_vecs); 155 156 memcpy(bio->bi_io_vec, rbio->bio.bi_io_vec, 157 sizeof(struct bio_vec) * rbio->bio.bi_vcnt); 158 swap(bio->bi_vcnt, rbio->bio.bi_vcnt); 159 160 bch2_data_update_read_done(&op->write, rbio->pick.crc); 161 } 162 163 static struct promote_op *__promote_alloc(struct btree_trans *trans, 164 enum btree_id btree_id, 165 struct bkey_s_c k, 166 struct bpos pos, 167 struct extent_ptr_decoded *pick, 168 struct bch_io_opts opts, 169 unsigned sectors, 170 struct bch_read_bio **rbio, 171 struct bch_io_failures *failed) 172 { 173 struct bch_fs *c = trans->c; 174 struct promote_op *op = NULL; 175 struct bio *bio; 176 unsigned pages = DIV_ROUND_UP(sectors, PAGE_SECTORS); 177 int ret; 178 179 if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_promote)) 180 return ERR_PTR(-BCH_ERR_nopromote_no_writes); 181 182 op = kzalloc(struct_size(op, bi_inline_vecs, pages), GFP_KERNEL); 183 if (!op) { 184 ret = -BCH_ERR_nopromote_enomem; 185 goto err; 186 } 187 188 op->start_time = local_clock(); 189 op->pos = pos; 190 191 /* 192 * We don't use the mempool here because extents that aren't 193 * checksummed or compressed can be too big for the mempool: 194 */ 195 *rbio = kzalloc(sizeof(struct bch_read_bio) + 196 sizeof(struct bio_vec) * pages, 197 GFP_KERNEL); 198 if (!*rbio) { 199 ret = -BCH_ERR_nopromote_enomem; 200 goto err; 201 } 202 203 rbio_init(&(*rbio)->bio, opts); 204 bio_init(&(*rbio)->bio, NULL, (*rbio)->bio.bi_inline_vecs, pages, 0); 205 206 if (bch2_bio_alloc_pages(&(*rbio)->bio, sectors << 9, GFP_KERNEL)) { 207 ret = -BCH_ERR_nopromote_enomem; 208 goto err; 209 } 210 211 (*rbio)->bounce = true; 212 (*rbio)->split = true; 213 (*rbio)->kmalloc = true; 214 215 if (rhashtable_lookup_insert_fast(&c->promote_table, &op->hash, 216 bch_promote_params)) { 217 ret = -BCH_ERR_nopromote_in_flight; 218 goto err; 219 } 220 221 bio = &op->write.op.wbio.bio; 222 bio_init(bio, NULL, bio->bi_inline_vecs, pages, 0); 223 224 struct data_update_opts update_opts = {}; 225 226 if (!failed) { 227 update_opts.target = opts.promote_target; 228 update_opts.extra_replicas = 1; 229 update_opts.write_flags = BCH_WRITE_ALLOC_NOWAIT|BCH_WRITE_CACHED; 230 } else { 231 update_opts.target = opts.foreground_target; 232 233 struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k); 234 unsigned i = 0; 235 bkey_for_each_ptr(ptrs, ptr) { 236 if (bch2_dev_io_failures(failed, ptr->dev)) 237 update_opts.rewrite_ptrs |= BIT(i); 238 i++; 239 } 240 } 241 242 ret = bch2_data_update_init(trans, NULL, NULL, &op->write, 243 writepoint_hashed((unsigned long) current), 244 opts, 245 update_opts, 246 btree_id, k); 247 /* 248 * possible errors: -BCH_ERR_nocow_lock_blocked, 249 * -BCH_ERR_ENOSPC_disk_reservation: 250 */ 251 if (ret) { 252 BUG_ON(rhashtable_remove_fast(&c->promote_table, &op->hash, 253 bch_promote_params)); 254 goto err; 255 } 256 257 op->write.op.end_io = promote_done; 258 259 return op; 260 err: 261 if (*rbio) 262 bio_free_pages(&(*rbio)->bio); 263 kfree(*rbio); 264 *rbio = NULL; 265 kfree(op); 266 bch2_write_ref_put(c, BCH_WRITE_REF_promote); 267 return ERR_PTR(ret); 268 } 269 270 noinline 271 static struct promote_op *promote_alloc(struct btree_trans *trans, 272 struct bvec_iter iter, 273 struct bkey_s_c k, 274 struct extent_ptr_decoded *pick, 275 struct bch_io_opts opts, 276 unsigned flags, 277 struct bch_read_bio **rbio, 278 bool *bounce, 279 bool *read_full, 280 struct bch_io_failures *failed) 281 { 282 struct bch_fs *c = trans->c; 283 /* 284 * if failed != NULL we're not actually doing a promote, we're 285 * recovering from an io/checksum error 286 */ 287 bool promote_full = (failed || 288 *read_full || 289 READ_ONCE(c->opts.promote_whole_extents)); 290 /* data might have to be decompressed in the write path: */ 291 unsigned sectors = promote_full 292 ? max(pick->crc.compressed_size, pick->crc.live_size) 293 : bvec_iter_sectors(iter); 294 struct bpos pos = promote_full 295 ? bkey_start_pos(k.k) 296 : POS(k.k->p.inode, iter.bi_sector); 297 struct promote_op *promote; 298 int ret; 299 300 ret = should_promote(c, k, pos, opts, flags, failed); 301 if (ret) 302 goto nopromote; 303 304 promote = __promote_alloc(trans, 305 k.k->type == KEY_TYPE_reflink_v 306 ? BTREE_ID_reflink 307 : BTREE_ID_extents, 308 k, pos, pick, opts, sectors, rbio, failed); 309 ret = PTR_ERR_OR_ZERO(promote); 310 if (ret) 311 goto nopromote; 312 313 *bounce = true; 314 *read_full = promote_full; 315 return promote; 316 nopromote: 317 trace_read_nopromote(c, ret); 318 return NULL; 319 } 320 321 /* Read */ 322 323 #define READ_RETRY_AVOID 1 324 #define READ_RETRY 2 325 #define READ_ERR 3 326 327 enum rbio_context { 328 RBIO_CONTEXT_NULL, 329 RBIO_CONTEXT_HIGHPRI, 330 RBIO_CONTEXT_UNBOUND, 331 }; 332 333 static inline struct bch_read_bio * 334 bch2_rbio_parent(struct bch_read_bio *rbio) 335 { 336 return rbio->split ? rbio->parent : rbio; 337 } 338 339 __always_inline 340 static void bch2_rbio_punt(struct bch_read_bio *rbio, work_func_t fn, 341 enum rbio_context context, 342 struct workqueue_struct *wq) 343 { 344 if (context <= rbio->context) { 345 fn(&rbio->work); 346 } else { 347 rbio->work.func = fn; 348 rbio->context = context; 349 queue_work(wq, &rbio->work); 350 } 351 } 352 353 static inline struct bch_read_bio *bch2_rbio_free(struct bch_read_bio *rbio) 354 { 355 BUG_ON(rbio->bounce && !rbio->split); 356 357 if (rbio->promote) 358 promote_free(rbio->c, rbio->promote); 359 rbio->promote = NULL; 360 361 if (rbio->bounce) 362 bch2_bio_free_pages_pool(rbio->c, &rbio->bio); 363 364 if (rbio->split) { 365 struct bch_read_bio *parent = rbio->parent; 366 367 if (rbio->kmalloc) 368 kfree(rbio); 369 else 370 bio_put(&rbio->bio); 371 372 rbio = parent; 373 } 374 375 return rbio; 376 } 377 378 /* 379 * Only called on a top level bch_read_bio to complete an entire read request, 380 * not a split: 381 */ 382 static void bch2_rbio_done(struct bch_read_bio *rbio) 383 { 384 if (rbio->start_time) 385 bch2_time_stats_update(&rbio->c->times[BCH_TIME_data_read], 386 rbio->start_time); 387 bio_endio(&rbio->bio); 388 } 389 390 static void bch2_read_retry_nodecode(struct bch_fs *c, struct bch_read_bio *rbio, 391 struct bvec_iter bvec_iter, 392 struct bch_io_failures *failed, 393 unsigned flags) 394 { 395 struct btree_trans *trans = bch2_trans_get(c); 396 struct btree_iter iter; 397 struct bkey_buf sk; 398 struct bkey_s_c k; 399 int ret; 400 401 flags &= ~BCH_READ_LAST_FRAGMENT; 402 flags |= BCH_READ_MUST_CLONE; 403 404 bch2_bkey_buf_init(&sk); 405 406 bch2_trans_iter_init(trans, &iter, rbio->data_btree, 407 rbio->read_pos, BTREE_ITER_slots); 408 retry: 409 bch2_trans_begin(trans); 410 rbio->bio.bi_status = 0; 411 412 k = bch2_btree_iter_peek_slot(&iter); 413 if (bkey_err(k)) 414 goto err; 415 416 bch2_bkey_buf_reassemble(&sk, c, k); 417 k = bkey_i_to_s_c(sk.k); 418 419 if (!bch2_bkey_matches_ptr(c, k, 420 rbio->pick.ptr, 421 rbio->data_pos.offset - 422 rbio->pick.crc.offset)) { 423 /* extent we wanted to read no longer exists: */ 424 rbio->hole = true; 425 goto out; 426 } 427 428 ret = __bch2_read_extent(trans, rbio, bvec_iter, 429 rbio->read_pos, 430 rbio->data_btree, 431 k, 0, failed, flags); 432 if (ret == READ_RETRY) 433 goto retry; 434 if (ret) 435 goto err; 436 out: 437 bch2_rbio_done(rbio); 438 bch2_trans_iter_exit(trans, &iter); 439 bch2_trans_put(trans); 440 bch2_bkey_buf_exit(&sk, c); 441 return; 442 err: 443 rbio->bio.bi_status = BLK_STS_IOERR; 444 goto out; 445 } 446 447 static void bch2_rbio_retry(struct work_struct *work) 448 { 449 struct bch_read_bio *rbio = 450 container_of(work, struct bch_read_bio, work); 451 struct bch_fs *c = rbio->c; 452 struct bvec_iter iter = rbio->bvec_iter; 453 unsigned flags = rbio->flags; 454 subvol_inum inum = { 455 .subvol = rbio->subvol, 456 .inum = rbio->read_pos.inode, 457 }; 458 struct bch_io_failures failed = { .nr = 0 }; 459 460 trace_and_count(c, read_retry, &rbio->bio); 461 462 if (rbio->retry == READ_RETRY_AVOID) 463 bch2_mark_io_failure(&failed, &rbio->pick); 464 465 rbio->bio.bi_status = 0; 466 467 rbio = bch2_rbio_free(rbio); 468 469 flags |= BCH_READ_IN_RETRY; 470 flags &= ~BCH_READ_MAY_PROMOTE; 471 472 if (flags & BCH_READ_NODECODE) { 473 bch2_read_retry_nodecode(c, rbio, iter, &failed, flags); 474 } else { 475 flags &= ~BCH_READ_LAST_FRAGMENT; 476 flags |= BCH_READ_MUST_CLONE; 477 478 __bch2_read(c, rbio, iter, inum, &failed, flags); 479 } 480 } 481 482 static void bch2_rbio_error(struct bch_read_bio *rbio, int retry, 483 blk_status_t error) 484 { 485 rbio->retry = retry; 486 487 if (rbio->flags & BCH_READ_IN_RETRY) 488 return; 489 490 if (retry == READ_ERR) { 491 rbio = bch2_rbio_free(rbio); 492 493 rbio->bio.bi_status = error; 494 bch2_rbio_done(rbio); 495 } else { 496 bch2_rbio_punt(rbio, bch2_rbio_retry, 497 RBIO_CONTEXT_UNBOUND, system_unbound_wq); 498 } 499 } 500 501 static int __bch2_rbio_narrow_crcs(struct btree_trans *trans, 502 struct bch_read_bio *rbio) 503 { 504 struct bch_fs *c = rbio->c; 505 u64 data_offset = rbio->data_pos.offset - rbio->pick.crc.offset; 506 struct bch_extent_crc_unpacked new_crc; 507 struct btree_iter iter; 508 struct bkey_i *new; 509 struct bkey_s_c k; 510 int ret = 0; 511 512 if (crc_is_compressed(rbio->pick.crc)) 513 return 0; 514 515 k = bch2_bkey_get_iter(trans, &iter, rbio->data_btree, rbio->data_pos, 516 BTREE_ITER_slots|BTREE_ITER_intent); 517 if ((ret = bkey_err(k))) 518 goto out; 519 520 if (bversion_cmp(k.k->bversion, rbio->version) || 521 !bch2_bkey_matches_ptr(c, k, rbio->pick.ptr, data_offset)) 522 goto out; 523 524 /* Extent was merged? */ 525 if (bkey_start_offset(k.k) < data_offset || 526 k.k->p.offset > data_offset + rbio->pick.crc.uncompressed_size) 527 goto out; 528 529 if (bch2_rechecksum_bio(c, &rbio->bio, rbio->version, 530 rbio->pick.crc, NULL, &new_crc, 531 bkey_start_offset(k.k) - data_offset, k.k->size, 532 rbio->pick.crc.csum_type)) { 533 bch_err(c, "error verifying existing checksum while narrowing checksum (memory corruption?)"); 534 ret = 0; 535 goto out; 536 } 537 538 /* 539 * going to be temporarily appending another checksum entry: 540 */ 541 new = bch2_trans_kmalloc(trans, bkey_bytes(k.k) + 542 sizeof(struct bch_extent_crc128)); 543 if ((ret = PTR_ERR_OR_ZERO(new))) 544 goto out; 545 546 bkey_reassemble(new, k); 547 548 if (!bch2_bkey_narrow_crcs(new, new_crc)) 549 goto out; 550 551 ret = bch2_trans_update(trans, &iter, new, 552 BTREE_UPDATE_internal_snapshot_node); 553 out: 554 bch2_trans_iter_exit(trans, &iter); 555 return ret; 556 } 557 558 static noinline void bch2_rbio_narrow_crcs(struct bch_read_bio *rbio) 559 { 560 bch2_trans_do(rbio->c, NULL, NULL, BCH_TRANS_COMMIT_no_enospc, 561 __bch2_rbio_narrow_crcs(trans, rbio)); 562 } 563 564 /* Inner part that may run in process context */ 565 static void __bch2_read_endio(struct work_struct *work) 566 { 567 struct bch_read_bio *rbio = 568 container_of(work, struct bch_read_bio, work); 569 struct bch_fs *c = rbio->c; 570 struct bio *src = &rbio->bio; 571 struct bio *dst = &bch2_rbio_parent(rbio)->bio; 572 struct bvec_iter dst_iter = rbio->bvec_iter; 573 struct bch_extent_crc_unpacked crc = rbio->pick.crc; 574 struct nonce nonce = extent_nonce(rbio->version, crc); 575 unsigned nofs_flags; 576 struct bch_csum csum; 577 int ret; 578 579 nofs_flags = memalloc_nofs_save(); 580 581 /* Reset iterator for checksumming and copying bounced data: */ 582 if (rbio->bounce) { 583 src->bi_iter.bi_size = crc.compressed_size << 9; 584 src->bi_iter.bi_idx = 0; 585 src->bi_iter.bi_bvec_done = 0; 586 } else { 587 src->bi_iter = rbio->bvec_iter; 588 } 589 590 csum = bch2_checksum_bio(c, crc.csum_type, nonce, src); 591 if (bch2_crc_cmp(csum, rbio->pick.crc.csum) && !c->opts.no_data_io) 592 goto csum_err; 593 594 /* 595 * XXX 596 * We need to rework the narrow_crcs path to deliver the read completion 597 * first, and then punt to a different workqueue, otherwise we're 598 * holding up reads while doing btree updates which is bad for memory 599 * reclaim. 600 */ 601 if (unlikely(rbio->narrow_crcs)) 602 bch2_rbio_narrow_crcs(rbio); 603 604 if (rbio->flags & BCH_READ_NODECODE) 605 goto nodecode; 606 607 /* Adjust crc to point to subset of data we want: */ 608 crc.offset += rbio->offset_into_extent; 609 crc.live_size = bvec_iter_sectors(rbio->bvec_iter); 610 611 if (crc_is_compressed(crc)) { 612 ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src); 613 if (ret) 614 goto decrypt_err; 615 616 if (bch2_bio_uncompress(c, src, dst, dst_iter, crc) && 617 !c->opts.no_data_io) 618 goto decompression_err; 619 } else { 620 /* don't need to decrypt the entire bio: */ 621 nonce = nonce_add(nonce, crc.offset << 9); 622 bio_advance(src, crc.offset << 9); 623 624 BUG_ON(src->bi_iter.bi_size < dst_iter.bi_size); 625 src->bi_iter.bi_size = dst_iter.bi_size; 626 627 ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src); 628 if (ret) 629 goto decrypt_err; 630 631 if (rbio->bounce) { 632 struct bvec_iter src_iter = src->bi_iter; 633 634 bio_copy_data_iter(dst, &dst_iter, src, &src_iter); 635 } 636 } 637 638 if (rbio->promote) { 639 /* 640 * Re encrypt data we decrypted, so it's consistent with 641 * rbio->crc: 642 */ 643 ret = bch2_encrypt_bio(c, crc.csum_type, nonce, src); 644 if (ret) 645 goto decrypt_err; 646 647 promote_start(rbio->promote, rbio); 648 rbio->promote = NULL; 649 } 650 nodecode: 651 if (likely(!(rbio->flags & BCH_READ_IN_RETRY))) { 652 rbio = bch2_rbio_free(rbio); 653 bch2_rbio_done(rbio); 654 } 655 out: 656 memalloc_nofs_restore(nofs_flags); 657 return; 658 csum_err: 659 /* 660 * Checksum error: if the bio wasn't bounced, we may have been 661 * reading into buffers owned by userspace (that userspace can 662 * scribble over) - retry the read, bouncing it this time: 663 */ 664 if (!rbio->bounce && (rbio->flags & BCH_READ_USER_MAPPED)) { 665 rbio->flags |= BCH_READ_MUST_BOUNCE; 666 bch2_rbio_error(rbio, READ_RETRY, BLK_STS_IOERR); 667 goto out; 668 } 669 670 struct printbuf buf = PRINTBUF; 671 buf.atomic++; 672 prt_str(&buf, "data "); 673 bch2_csum_err_msg(&buf, crc.csum_type, rbio->pick.crc.csum, csum); 674 675 struct bch_dev *ca = rbio->have_ioref ? bch2_dev_have_ref(c, rbio->pick.ptr.dev) : NULL; 676 if (ca) { 677 bch_err_inum_offset_ratelimited(ca, 678 rbio->read_pos.inode, 679 rbio->read_pos.offset << 9, 680 "data %s", buf.buf); 681 bch2_io_error(ca, BCH_MEMBER_ERROR_checksum); 682 } 683 printbuf_exit(&buf); 684 bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR); 685 goto out; 686 decompression_err: 687 bch_err_inum_offset_ratelimited(c, rbio->read_pos.inode, 688 rbio->read_pos.offset << 9, 689 "decompression error"); 690 bch2_rbio_error(rbio, READ_ERR, BLK_STS_IOERR); 691 goto out; 692 decrypt_err: 693 bch_err_inum_offset_ratelimited(c, rbio->read_pos.inode, 694 rbio->read_pos.offset << 9, 695 "decrypt error"); 696 bch2_rbio_error(rbio, READ_ERR, BLK_STS_IOERR); 697 goto out; 698 } 699 700 static void bch2_read_endio(struct bio *bio) 701 { 702 struct bch_read_bio *rbio = 703 container_of(bio, struct bch_read_bio, bio); 704 struct bch_fs *c = rbio->c; 705 struct bch_dev *ca = rbio->have_ioref ? bch2_dev_have_ref(c, rbio->pick.ptr.dev) : NULL; 706 struct workqueue_struct *wq = NULL; 707 enum rbio_context context = RBIO_CONTEXT_NULL; 708 709 if (rbio->have_ioref) { 710 bch2_latency_acct(ca, rbio->submit_time, READ); 711 percpu_ref_put(&ca->io_ref); 712 } 713 714 if (!rbio->split) 715 rbio->bio.bi_end_io = rbio->end_io; 716 717 if (bio->bi_status) { 718 if (ca) { 719 bch_err_inum_offset_ratelimited(ca, 720 rbio->read_pos.inode, 721 rbio->read_pos.offset, 722 "data read error: %s", 723 bch2_blk_status_to_str(bio->bi_status)); 724 bch2_io_error(ca, BCH_MEMBER_ERROR_read); 725 } 726 bch2_rbio_error(rbio, READ_RETRY_AVOID, bio->bi_status); 727 return; 728 } 729 730 if (((rbio->flags & BCH_READ_RETRY_IF_STALE) && race_fault()) || 731 (ca && dev_ptr_stale(ca, &rbio->pick.ptr))) { 732 trace_and_count(c, read_reuse_race, &rbio->bio); 733 734 if (rbio->flags & BCH_READ_RETRY_IF_STALE) 735 bch2_rbio_error(rbio, READ_RETRY, BLK_STS_AGAIN); 736 else 737 bch2_rbio_error(rbio, READ_ERR, BLK_STS_AGAIN); 738 return; 739 } 740 741 if (rbio->narrow_crcs || 742 rbio->promote || 743 crc_is_compressed(rbio->pick.crc) || 744 bch2_csum_type_is_encryption(rbio->pick.crc.csum_type)) 745 context = RBIO_CONTEXT_UNBOUND, wq = system_unbound_wq; 746 else if (rbio->pick.crc.csum_type) 747 context = RBIO_CONTEXT_HIGHPRI, wq = system_highpri_wq; 748 749 bch2_rbio_punt(rbio, __bch2_read_endio, context, wq); 750 } 751 752 int __bch2_read_indirect_extent(struct btree_trans *trans, 753 unsigned *offset_into_extent, 754 struct bkey_buf *orig_k) 755 { 756 struct btree_iter iter; 757 struct bkey_s_c k; 758 u64 reflink_offset; 759 int ret; 760 761 reflink_offset = le64_to_cpu(bkey_i_to_reflink_p(orig_k->k)->v.idx) + 762 *offset_into_extent; 763 764 k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_reflink, 765 POS(0, reflink_offset), 0); 766 ret = bkey_err(k); 767 if (ret) 768 goto err; 769 770 if (k.k->type != KEY_TYPE_reflink_v && 771 k.k->type != KEY_TYPE_indirect_inline_data) { 772 bch_err_inum_offset_ratelimited(trans->c, 773 orig_k->k->k.p.inode, 774 orig_k->k->k.p.offset << 9, 775 "%llu len %u points to nonexistent indirect extent %llu", 776 orig_k->k->k.p.offset, 777 orig_k->k->k.size, 778 reflink_offset); 779 bch2_inconsistent_error(trans->c); 780 ret = -BCH_ERR_missing_indirect_extent; 781 goto err; 782 } 783 784 *offset_into_extent = iter.pos.offset - bkey_start_offset(k.k); 785 bch2_bkey_buf_reassemble(orig_k, trans->c, k); 786 err: 787 bch2_trans_iter_exit(trans, &iter); 788 return ret; 789 } 790 791 static noinline void read_from_stale_dirty_pointer(struct btree_trans *trans, 792 struct bch_dev *ca, 793 struct bkey_s_c k, 794 struct bch_extent_ptr ptr) 795 { 796 struct bch_fs *c = trans->c; 797 struct btree_iter iter; 798 struct printbuf buf = PRINTBUF; 799 int ret; 800 801 bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc, 802 PTR_BUCKET_POS(ca, &ptr), 803 BTREE_ITER_cached); 804 805 u8 *gen = bucket_gen(ca, iter.pos.offset); 806 if (gen) { 807 808 prt_printf(&buf, "Attempting to read from stale dirty pointer:\n"); 809 printbuf_indent_add(&buf, 2); 810 811 bch2_bkey_val_to_text(&buf, c, k); 812 prt_newline(&buf); 813 814 prt_printf(&buf, "memory gen: %u", *gen); 815 816 ret = lockrestart_do(trans, bkey_err(k = bch2_btree_iter_peek_slot(&iter))); 817 if (!ret) { 818 prt_newline(&buf); 819 bch2_bkey_val_to_text(&buf, c, k); 820 } 821 } else { 822 prt_printf(&buf, "Attempting to read from invalid bucket %llu:%llu:\n", 823 iter.pos.inode, iter.pos.offset); 824 printbuf_indent_add(&buf, 2); 825 826 prt_printf(&buf, "first bucket %u nbuckets %llu\n", 827 ca->mi.first_bucket, ca->mi.nbuckets); 828 829 bch2_bkey_val_to_text(&buf, c, k); 830 prt_newline(&buf); 831 } 832 833 bch2_fs_inconsistent(c, "%s", buf.buf); 834 835 bch2_trans_iter_exit(trans, &iter); 836 printbuf_exit(&buf); 837 } 838 839 int __bch2_read_extent(struct btree_trans *trans, struct bch_read_bio *orig, 840 struct bvec_iter iter, struct bpos read_pos, 841 enum btree_id data_btree, struct bkey_s_c k, 842 unsigned offset_into_extent, 843 struct bch_io_failures *failed, unsigned flags) 844 { 845 struct bch_fs *c = trans->c; 846 struct extent_ptr_decoded pick; 847 struct bch_read_bio *rbio = NULL; 848 struct promote_op *promote = NULL; 849 bool bounce = false, read_full = false, narrow_crcs = false; 850 struct bpos data_pos = bkey_start_pos(k.k); 851 int pick_ret; 852 853 if (bkey_extent_is_inline_data(k.k)) { 854 unsigned bytes = min_t(unsigned, iter.bi_size, 855 bkey_inline_data_bytes(k.k)); 856 857 swap(iter.bi_size, bytes); 858 memcpy_to_bio(&orig->bio, iter, bkey_inline_data_p(k)); 859 swap(iter.bi_size, bytes); 860 bio_advance_iter(&orig->bio, &iter, bytes); 861 zero_fill_bio_iter(&orig->bio, iter); 862 goto out_read_done; 863 } 864 retry_pick: 865 pick_ret = bch2_bkey_pick_read_device(c, k, failed, &pick); 866 867 /* hole or reservation - just zero fill: */ 868 if (!pick_ret) 869 goto hole; 870 871 if (pick_ret < 0) { 872 struct printbuf buf = PRINTBUF; 873 bch2_bkey_val_to_text(&buf, c, k); 874 875 bch_err_inum_offset_ratelimited(c, 876 read_pos.inode, read_pos.offset << 9, 877 "no device to read from: %s\n %s", 878 bch2_err_str(pick_ret), 879 buf.buf); 880 printbuf_exit(&buf); 881 goto err; 882 } 883 884 struct bch_dev *ca = bch2_dev_get_ioref(c, pick.ptr.dev, READ); 885 886 /* 887 * Stale dirty pointers are treated as IO errors, but @failed isn't 888 * allocated unless we're in the retry path - so if we're not in the 889 * retry path, don't check here, it'll be caught in bch2_read_endio() 890 * and we'll end up in the retry path: 891 */ 892 if ((flags & BCH_READ_IN_RETRY) && 893 !pick.ptr.cached && 894 ca && 895 unlikely(dev_ptr_stale(ca, &pick.ptr))) { 896 read_from_stale_dirty_pointer(trans, ca, k, pick.ptr); 897 bch2_mark_io_failure(failed, &pick); 898 percpu_ref_put(&ca->io_ref); 899 goto retry_pick; 900 } 901 902 /* 903 * Unlock the iterator while the btree node's lock is still in 904 * cache, before doing the IO: 905 */ 906 bch2_trans_unlock(trans); 907 908 if (flags & BCH_READ_NODECODE) { 909 /* 910 * can happen if we retry, and the extent we were going to read 911 * has been merged in the meantime: 912 */ 913 if (pick.crc.compressed_size > orig->bio.bi_vcnt * PAGE_SECTORS) { 914 if (ca) 915 percpu_ref_put(&ca->io_ref); 916 goto hole; 917 } 918 919 iter.bi_size = pick.crc.compressed_size << 9; 920 goto get_bio; 921 } 922 923 if (!(flags & BCH_READ_LAST_FRAGMENT) || 924 bio_flagged(&orig->bio, BIO_CHAIN)) 925 flags |= BCH_READ_MUST_CLONE; 926 927 narrow_crcs = !(flags & BCH_READ_IN_RETRY) && 928 bch2_can_narrow_extent_crcs(k, pick.crc); 929 930 if (narrow_crcs && (flags & BCH_READ_USER_MAPPED)) 931 flags |= BCH_READ_MUST_BOUNCE; 932 933 EBUG_ON(offset_into_extent + bvec_iter_sectors(iter) > k.k->size); 934 935 if (crc_is_compressed(pick.crc) || 936 (pick.crc.csum_type != BCH_CSUM_none && 937 (bvec_iter_sectors(iter) != pick.crc.uncompressed_size || 938 (bch2_csum_type_is_encryption(pick.crc.csum_type) && 939 (flags & BCH_READ_USER_MAPPED)) || 940 (flags & BCH_READ_MUST_BOUNCE)))) { 941 read_full = true; 942 bounce = true; 943 } 944 945 if (orig->opts.promote_target)// || failed) 946 promote = promote_alloc(trans, iter, k, &pick, orig->opts, flags, 947 &rbio, &bounce, &read_full, failed); 948 949 if (!read_full) { 950 EBUG_ON(crc_is_compressed(pick.crc)); 951 EBUG_ON(pick.crc.csum_type && 952 (bvec_iter_sectors(iter) != pick.crc.uncompressed_size || 953 bvec_iter_sectors(iter) != pick.crc.live_size || 954 pick.crc.offset || 955 offset_into_extent)); 956 957 data_pos.offset += offset_into_extent; 958 pick.ptr.offset += pick.crc.offset + 959 offset_into_extent; 960 offset_into_extent = 0; 961 pick.crc.compressed_size = bvec_iter_sectors(iter); 962 pick.crc.uncompressed_size = bvec_iter_sectors(iter); 963 pick.crc.offset = 0; 964 pick.crc.live_size = bvec_iter_sectors(iter); 965 } 966 get_bio: 967 if (rbio) { 968 /* 969 * promote already allocated bounce rbio: 970 * promote needs to allocate a bio big enough for uncompressing 971 * data in the write path, but we're not going to use it all 972 * here: 973 */ 974 EBUG_ON(rbio->bio.bi_iter.bi_size < 975 pick.crc.compressed_size << 9); 976 rbio->bio.bi_iter.bi_size = 977 pick.crc.compressed_size << 9; 978 } else if (bounce) { 979 unsigned sectors = pick.crc.compressed_size; 980 981 rbio = rbio_init(bio_alloc_bioset(NULL, 982 DIV_ROUND_UP(sectors, PAGE_SECTORS), 983 0, 984 GFP_NOFS, 985 &c->bio_read_split), 986 orig->opts); 987 988 bch2_bio_alloc_pages_pool(c, &rbio->bio, sectors << 9); 989 rbio->bounce = true; 990 rbio->split = true; 991 } else if (flags & BCH_READ_MUST_CLONE) { 992 /* 993 * Have to clone if there were any splits, due to error 994 * reporting issues (if a split errored, and retrying didn't 995 * work, when it reports the error to its parent (us) we don't 996 * know if the error was from our bio, and we should retry, or 997 * from the whole bio, in which case we don't want to retry and 998 * lose the error) 999 */ 1000 rbio = rbio_init(bio_alloc_clone(NULL, &orig->bio, GFP_NOFS, 1001 &c->bio_read_split), 1002 orig->opts); 1003 rbio->bio.bi_iter = iter; 1004 rbio->split = true; 1005 } else { 1006 rbio = orig; 1007 rbio->bio.bi_iter = iter; 1008 EBUG_ON(bio_flagged(&rbio->bio, BIO_CHAIN)); 1009 } 1010 1011 EBUG_ON(bio_sectors(&rbio->bio) != pick.crc.compressed_size); 1012 1013 rbio->c = c; 1014 rbio->submit_time = local_clock(); 1015 if (rbio->split) 1016 rbio->parent = orig; 1017 else 1018 rbio->end_io = orig->bio.bi_end_io; 1019 rbio->bvec_iter = iter; 1020 rbio->offset_into_extent= offset_into_extent; 1021 rbio->flags = flags; 1022 rbio->have_ioref = ca != NULL; 1023 rbio->narrow_crcs = narrow_crcs; 1024 rbio->hole = 0; 1025 rbio->retry = 0; 1026 rbio->context = 0; 1027 /* XXX: only initialize this if needed */ 1028 rbio->devs_have = bch2_bkey_devs(k); 1029 rbio->pick = pick; 1030 rbio->subvol = orig->subvol; 1031 rbio->read_pos = read_pos; 1032 rbio->data_btree = data_btree; 1033 rbio->data_pos = data_pos; 1034 rbio->version = k.k->bversion; 1035 rbio->promote = promote; 1036 INIT_WORK(&rbio->work, NULL); 1037 1038 if (flags & BCH_READ_NODECODE) 1039 orig->pick = pick; 1040 1041 rbio->bio.bi_opf = orig->bio.bi_opf; 1042 rbio->bio.bi_iter.bi_sector = pick.ptr.offset; 1043 rbio->bio.bi_end_io = bch2_read_endio; 1044 1045 if (rbio->bounce) 1046 trace_and_count(c, read_bounce, &rbio->bio); 1047 1048 this_cpu_add(c->counters[BCH_COUNTER_io_read], bio_sectors(&rbio->bio)); 1049 bch2_increment_clock(c, bio_sectors(&rbio->bio), READ); 1050 1051 /* 1052 * If it's being moved internally, we don't want to flag it as a cache 1053 * hit: 1054 */ 1055 if (ca && pick.ptr.cached && !(flags & BCH_READ_NODECODE)) 1056 bch2_bucket_io_time_reset(trans, pick.ptr.dev, 1057 PTR_BUCKET_NR(ca, &pick.ptr), READ); 1058 1059 if (!(flags & (BCH_READ_IN_RETRY|BCH_READ_LAST_FRAGMENT))) { 1060 bio_inc_remaining(&orig->bio); 1061 trace_and_count(c, read_split, &orig->bio); 1062 } 1063 1064 if (!rbio->pick.idx) { 1065 if (!rbio->have_ioref) { 1066 bch_err_inum_offset_ratelimited(c, 1067 read_pos.inode, 1068 read_pos.offset << 9, 1069 "no device to read from"); 1070 bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR); 1071 goto out; 1072 } 1073 1074 this_cpu_add(ca->io_done->sectors[READ][BCH_DATA_user], 1075 bio_sectors(&rbio->bio)); 1076 bio_set_dev(&rbio->bio, ca->disk_sb.bdev); 1077 1078 if (unlikely(c->opts.no_data_io)) { 1079 if (likely(!(flags & BCH_READ_IN_RETRY))) 1080 bio_endio(&rbio->bio); 1081 } else { 1082 if (likely(!(flags & BCH_READ_IN_RETRY))) 1083 submit_bio(&rbio->bio); 1084 else 1085 submit_bio_wait(&rbio->bio); 1086 } 1087 1088 /* 1089 * We just submitted IO which may block, we expect relock fail 1090 * events and shouldn't count them: 1091 */ 1092 trans->notrace_relock_fail = true; 1093 } else { 1094 /* Attempting reconstruct read: */ 1095 if (bch2_ec_read_extent(trans, rbio, k)) { 1096 bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR); 1097 goto out; 1098 } 1099 1100 if (likely(!(flags & BCH_READ_IN_RETRY))) 1101 bio_endio(&rbio->bio); 1102 } 1103 out: 1104 if (likely(!(flags & BCH_READ_IN_RETRY))) { 1105 return 0; 1106 } else { 1107 int ret; 1108 1109 rbio->context = RBIO_CONTEXT_UNBOUND; 1110 bch2_read_endio(&rbio->bio); 1111 1112 ret = rbio->retry; 1113 rbio = bch2_rbio_free(rbio); 1114 1115 if (ret == READ_RETRY_AVOID) { 1116 bch2_mark_io_failure(failed, &pick); 1117 ret = READ_RETRY; 1118 } 1119 1120 if (!ret) 1121 goto out_read_done; 1122 1123 return ret; 1124 } 1125 1126 err: 1127 if (flags & BCH_READ_IN_RETRY) 1128 return READ_ERR; 1129 1130 orig->bio.bi_status = BLK_STS_IOERR; 1131 goto out_read_done; 1132 1133 hole: 1134 /* 1135 * won't normally happen in the BCH_READ_NODECODE 1136 * (bch2_move_extent()) path, but if we retry and the extent we wanted 1137 * to read no longer exists we have to signal that: 1138 */ 1139 if (flags & BCH_READ_NODECODE) 1140 orig->hole = true; 1141 1142 zero_fill_bio_iter(&orig->bio, iter); 1143 out_read_done: 1144 if (flags & BCH_READ_LAST_FRAGMENT) 1145 bch2_rbio_done(orig); 1146 return 0; 1147 } 1148 1149 void __bch2_read(struct bch_fs *c, struct bch_read_bio *rbio, 1150 struct bvec_iter bvec_iter, subvol_inum inum, 1151 struct bch_io_failures *failed, unsigned flags) 1152 { 1153 struct btree_trans *trans = bch2_trans_get(c); 1154 struct btree_iter iter; 1155 struct bkey_buf sk; 1156 struct bkey_s_c k; 1157 int ret; 1158 1159 BUG_ON(flags & BCH_READ_NODECODE); 1160 1161 bch2_bkey_buf_init(&sk); 1162 bch2_trans_iter_init(trans, &iter, BTREE_ID_extents, 1163 POS(inum.inum, bvec_iter.bi_sector), 1164 BTREE_ITER_slots); 1165 1166 while (1) { 1167 unsigned bytes, sectors, offset_into_extent; 1168 enum btree_id data_btree = BTREE_ID_extents; 1169 1170 bch2_trans_begin(trans); 1171 1172 u32 snapshot; 1173 ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot); 1174 if (ret) 1175 goto err; 1176 1177 bch2_btree_iter_set_snapshot(&iter, snapshot); 1178 1179 bch2_btree_iter_set_pos(&iter, 1180 POS(inum.inum, bvec_iter.bi_sector)); 1181 1182 k = bch2_btree_iter_peek_slot(&iter); 1183 ret = bkey_err(k); 1184 if (ret) 1185 goto err; 1186 1187 offset_into_extent = iter.pos.offset - 1188 bkey_start_offset(k.k); 1189 sectors = k.k->size - offset_into_extent; 1190 1191 bch2_bkey_buf_reassemble(&sk, c, k); 1192 1193 ret = bch2_read_indirect_extent(trans, &data_btree, 1194 &offset_into_extent, &sk); 1195 if (ret) 1196 goto err; 1197 1198 k = bkey_i_to_s_c(sk.k); 1199 1200 /* 1201 * With indirect extents, the amount of data to read is the min 1202 * of the original extent and the indirect extent: 1203 */ 1204 sectors = min(sectors, k.k->size - offset_into_extent); 1205 1206 bytes = min(sectors, bvec_iter_sectors(bvec_iter)) << 9; 1207 swap(bvec_iter.bi_size, bytes); 1208 1209 if (bvec_iter.bi_size == bytes) 1210 flags |= BCH_READ_LAST_FRAGMENT; 1211 1212 ret = __bch2_read_extent(trans, rbio, bvec_iter, iter.pos, 1213 data_btree, k, 1214 offset_into_extent, failed, flags); 1215 if (ret) 1216 goto err; 1217 1218 if (flags & BCH_READ_LAST_FRAGMENT) 1219 break; 1220 1221 swap(bvec_iter.bi_size, bytes); 1222 bio_advance_iter(&rbio->bio, &bvec_iter, bytes); 1223 err: 1224 if (ret && 1225 !bch2_err_matches(ret, BCH_ERR_transaction_restart) && 1226 ret != READ_RETRY && 1227 ret != READ_RETRY_AVOID) 1228 break; 1229 } 1230 1231 bch2_trans_iter_exit(trans, &iter); 1232 bch2_trans_put(trans); 1233 bch2_bkey_buf_exit(&sk, c); 1234 1235 if (ret) { 1236 bch_err_inum_offset_ratelimited(c, inum.inum, 1237 bvec_iter.bi_sector << 9, 1238 "read error %i from btree lookup", ret); 1239 rbio->bio.bi_status = BLK_STS_IOERR; 1240 bch2_rbio_done(rbio); 1241 } 1242 } 1243 1244 void bch2_fs_io_read_exit(struct bch_fs *c) 1245 { 1246 if (c->promote_table.tbl) 1247 rhashtable_destroy(&c->promote_table); 1248 bioset_exit(&c->bio_read_split); 1249 bioset_exit(&c->bio_read); 1250 } 1251 1252 int bch2_fs_io_read_init(struct bch_fs *c) 1253 { 1254 if (bioset_init(&c->bio_read, 1, offsetof(struct bch_read_bio, bio), 1255 BIOSET_NEED_BVECS)) 1256 return -BCH_ERR_ENOMEM_bio_read_init; 1257 1258 if (bioset_init(&c->bio_read_split, 1, offsetof(struct bch_read_bio, bio), 1259 BIOSET_NEED_BVECS)) 1260 return -BCH_ERR_ENOMEM_bio_read_split_init; 1261 1262 if (rhashtable_init(&c->promote_table, &bch_promote_params)) 1263 return -BCH_ERR_ENOMEM_promote_table_init; 1264 1265 return 0; 1266 } 1267