git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/io.c

   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_foreground.h"
  11 #include "bkey_on_stack.h"
  12 #include "bset.h"
  13 #include "btree_update.h"
  14 #include "buckets.h"
  15 #include "checksum.h"
  16 #include "compress.h"
  17 #include "clock.h"
  18 #include "debug.h"
  19 #include "disk_groups.h"
  20 #include "ec.h"
  21 #include "error.h"
  22 #include "extent_update.h"
  23 #include "inode.h"
  24 #include "io.h"
  25 #include "journal.h"
  26 #include "keylist.h"
  27 #include "move.h"
  28 #include "rebalance.h"
  29 #include "super.h"
  30 #include "super-io.h"
  31
  32 #include <linux/blkdev.h>
  33 #include <linux/random.h>
  34
  35 #include <trace/events/bcachefs.h>
  36
  37 static bool bch2_target_congested(struct bch_fs *c, u16 target)
  38 {
  39         const struct bch_devs_mask *devs;
  40         unsigned d, nr = 0, total = 0;
  41         u64 now = local_clock(), last;
  42         s64 congested;
  43         struct bch_dev *ca;
  44
  45         if (!target)
  46                 return false;
  47
  48         rcu_read_lock();
  49         devs = bch2_target_to_mask(c, target);
  50         for_each_set_bit(d, devs->d, BCH_SB_MEMBERS_MAX) {
  51                 ca = rcu_dereference(c->devs[d]);
  52                 if (!ca)
  53                         continue;
  54
  55                 congested = atomic_read(&ca->congested);
  56                 last = READ_ONCE(ca->congested_last);
  57                 if (time_after64(now, last))
  58                         congested -= (now - last) >> 12;
  59
  60                 total += max(congested, 0LL);
  61                 nr++;
  62         }
  63         rcu_read_unlock();
  64
  65         return bch2_rand_range(nr * CONGESTED_MAX) < total;
  66 }
  67
  68 static inline void bch2_congested_acct(struct bch_dev *ca, u64 io_latency,
  69                                        u64 now, int rw)
  70 {
  71         u64 latency_capable =
  72                 ca->io_latency[rw].quantiles.entries[QUANTILE_IDX(1)].m;
  73         /* ideally we'd be taking into account the device's variance here: */
  74         u64 latency_threshold = latency_capable << (rw == READ ? 2 : 3);
  75         s64 latency_over = io_latency - latency_threshold;
  76
  77         if (latency_threshold && latency_over > 0) {
  78                 /*
  79                  * bump up congested by approximately latency_over * 4 /
  80                  * latency_threshold - we don't need much accuracy here so don't
  81                  * bother with the divide:
  82                  */
  83                 if (atomic_read(&ca->congested) < CONGESTED_MAX)
  84                         atomic_add(latency_over >>
  85                                    max_t(int, ilog2(latency_threshold) - 2, 0),
  86                                    &ca->congested);
  87
  88                 ca->congested_last = now;
  89         } else if (atomic_read(&ca->congested) > 0) {
  90                 atomic_dec(&ca->congested);
  91         }
  92 }
  93
  94 void bch2_latency_acct(struct bch_dev *ca, u64 submit_time, int rw)
  95 {
  96         atomic64_t *latency = &ca->cur_latency[rw];
  97         u64 now = local_clock();
  98         u64 io_latency = time_after64(now, submit_time)
  99                 ? now - submit_time
 100                 : 0;
 101         u64 old, new, v = atomic64_read(latency);
 102
 103         do {
 104                 old = v;
 105
 106                 /*
 107                  * If the io latency was reasonably close to the current
 108                  * latency, skip doing the update and atomic operation - most of
 109                  * the time:
 110                  */
 111                 if (abs((int) (old - io_latency)) < (old >> 1) &&
 112                     now & ~(~0 << 5))
 113                         break;
 114
 115                 new = ewma_add(old, io_latency, 5);
 116         } while ((v = atomic64_cmpxchg(latency, old, new)) != old);
 117
 118         bch2_congested_acct(ca, io_latency, now, rw);
 119
 120         __bch2_time_stats_update(&ca->io_latency[rw], submit_time, now);
 121 }
 122
 123 /* Allocate, free from mempool: */
 124
 125 void bch2_bio_free_pages_pool(struct bch_fs *c, struct bio *bio)
 126 {
 127         struct bvec_iter_all iter;
 128         struct bio_vec *bv;
 129
 130         bio_for_each_segment_all(bv, bio, iter)
 131                 if (bv->bv_page != ZERO_PAGE(0))
 132                         mempool_free(bv->bv_page, &c->bio_bounce_pages);
 133         bio->bi_vcnt = 0;
 134 }
 135
 136 static struct page *__bio_alloc_page_pool(struct bch_fs *c, bool *using_mempool)
 137 {
 138         struct page *page;
 139
 140         if (likely(!*using_mempool)) {
 141                 page = alloc_page(GFP_NOIO);
 142                 if (unlikely(!page)) {
 143                         mutex_lock(&c->bio_bounce_pages_lock);
 144                         *using_mempool = true;
 145                         goto pool_alloc;
 146
 147                 }
 148         } else {
 149 pool_alloc:
 150                 page = mempool_alloc(&c->bio_bounce_pages, GFP_NOIO);
 151         }
 152
 153         return page;
 154 }
 155
 156 void bch2_bio_alloc_pages_pool(struct bch_fs *c, struct bio *bio,
 157                                size_t size)
 158 {
 159         bool using_mempool = false;
 160
 161         while (size) {
 162                 struct page *page = __bio_alloc_page_pool(c, &using_mempool);
 163                 unsigned len = min(PAGE_SIZE, size);
 164
 165                 BUG_ON(!bio_add_page(bio, page, len, 0));
 166                 size -= len;
 167         }
 168
 169         if (using_mempool)
 170                 mutex_unlock(&c->bio_bounce_pages_lock);
 171 }
 172
 173 /* Extent update path: */
 174
 175 static int sum_sector_overwrites(struct btree_trans *trans,
 176                                  struct btree_iter *extent_iter,
 177                                  struct bkey_i *new,
 178                                  bool may_allocate,
 179                                  bool *maybe_extending,
 180                                  s64 *delta)
 181 {
 182         struct btree_iter *iter;
 183         struct bkey_s_c old;
 184         int ret = 0;
 185
 186         *maybe_extending = true;
 187         *delta = 0;
 188
 189         iter = bch2_trans_copy_iter(trans, extent_iter);
 190         if (IS_ERR(iter))
 191                 return PTR_ERR(iter);
 192
 193         for_each_btree_key_continue(iter, BTREE_ITER_SLOTS, old, ret) {
 194                 if (!may_allocate &&
 195                     bch2_bkey_nr_ptrs_fully_allocated(old) <
 196                     bch2_bkey_nr_ptrs_allocated(bkey_i_to_s_c(new))) {
 197                         ret = -ENOSPC;
 198                         break;
 199                 }
 200
 201                 *delta += (min(new->k.p.offset,
 202                               old.k->p.offset) -
 203                           max(bkey_start_offset(&new->k),
 204                               bkey_start_offset(old.k))) *
 205                         (bkey_extent_is_allocation(&new->k) -
 206                          bkey_extent_is_allocation(old.k));
 207
 208                 if (bkey_cmp(old.k->p, new->k.p) >= 0) {
 209                         /*
 210                          * Check if there's already data above where we're
 211                          * going to be writing to - this means we're definitely
 212                          * not extending the file:
 213                          *
 214                          * Note that it's not sufficient to check if there's
 215                          * data up to the sector offset we're going to be
 216                          * writing to, because i_size could be up to one block
 217                          * less:
 218                          */
 219                         if (!bkey_cmp(old.k->p, new->k.p))
 220                                 old = bch2_btree_iter_next(iter);
 221
 222                         if (old.k && !bkey_err(old) &&
 223                             old.k->p.inode == extent_iter->pos.inode &&
 224                             bkey_extent_is_data(old.k))
 225                                 *maybe_extending = false;
 226
 227                         break;
 228                 }
 229         }
 230
 231         bch2_trans_iter_put(trans, iter);
 232         return ret;
 233 }
 234
 235 int bch2_extent_update(struct btree_trans *trans,
 236                        struct btree_iter *iter,
 237                        struct bkey_i *k,
 238                        struct disk_reservation *disk_res,
 239                        u64 *journal_seq,
 240                        u64 new_i_size,
 241                        s64 *i_sectors_delta)
 242 {
 243         /* this must live until after bch2_trans_commit(): */
 244         struct bkey_inode_buf inode_p;
 245         bool extending = false;
 246         s64 delta = 0;
 247         int ret;
 248
 249         ret = bch2_extent_trim_atomic(k, iter);
 250         if (ret)
 251                 return ret;
 252
 253         ret = sum_sector_overwrites(trans, iter, k,
 254                         disk_res && disk_res->sectors != 0,
 255                         &extending, &delta);
 256         if (ret)
 257                 return ret;
 258
 259         new_i_size = extending
 260                 ? min(k->k.p.offset << 9, new_i_size)
 261                 : 0;
 262
 263         if (delta || new_i_size) {
 264                 struct btree_iter *inode_iter;
 265                 struct bch_inode_unpacked inode_u;
 266
 267                 inode_iter = bch2_inode_peek(trans, &inode_u,
 268                                 k->k.p.inode, BTREE_ITER_INTENT);
 269                 if (IS_ERR(inode_iter))
 270                         return PTR_ERR(inode_iter);
 271
 272                 /*
 273                  * XXX:
 274                  * writeback can race a bit with truncate, because truncate
 275                  * first updates the inode then truncates the pagecache. This is
 276                  * ugly, but lets us preserve the invariant that the in memory
 277                  * i_size is always >= the on disk i_size.
 278                  *
 279                 BUG_ON(new_i_size > inode_u.bi_size &&
 280                        (inode_u.bi_flags & BCH_INODE_I_SIZE_DIRTY));
 281                  */
 282                 BUG_ON(new_i_size > inode_u.bi_size && !extending);
 283
 284                 if (!(inode_u.bi_flags & BCH_INODE_I_SIZE_DIRTY) &&
 285                     new_i_size > inode_u.bi_size)
 286                         inode_u.bi_size = new_i_size;
 287                 else
 288                         new_i_size = 0;
 289
 290                 inode_u.bi_sectors += delta;
 291
 292                 if (delta || new_i_size) {
 293                         bch2_inode_pack(&inode_p, &inode_u);
 294                         bch2_trans_update(trans, inode_iter,
 295                                           &inode_p.inode.k_i, 0);
 296                 }
 297
 298                 bch2_trans_iter_put(trans, inode_iter);
 299         }
 300
 301         bch2_trans_update(trans, iter, k, 0);
 302
 303         ret = bch2_trans_commit(trans, disk_res, journal_seq,
 304                                 BTREE_INSERT_NOCHECK_RW|
 305                                 BTREE_INSERT_NOFAIL|
 306                                 BTREE_INSERT_USE_RESERVE);
 307         if (!ret && i_sectors_delta)
 308                 *i_sectors_delta += delta;
 309
 310         return ret;
 311 }
 312
 313 int bch2_fpunch_at(struct btree_trans *trans, struct btree_iter *iter,
 314                    struct bpos end, u64 *journal_seq,
 315                    s64 *i_sectors_delta)
 316 {
 317         struct bch_fs *c        = trans->c;
 318         unsigned max_sectors    = KEY_SIZE_MAX & (~0 << c->block_bits);
 319         struct bkey_s_c k;
 320         int ret = 0, ret2 = 0;
 321
 322         while ((k = bch2_btree_iter_peek(iter)).k &&
 323                bkey_cmp(iter->pos, end) < 0) {
 324                 struct disk_reservation disk_res =
 325                         bch2_disk_reservation_init(c, 0);
 326                 struct bkey_i delete;
 327
 328                 bch2_trans_begin(trans);
 329
 330                 ret = bkey_err(k);
 331                 if (ret)
 332                         goto btree_err;
 333
 334                 bkey_init(&delete.k);
 335                 delete.k.p = iter->pos;
 336
 337                 /* create the biggest key we can */
 338                 bch2_key_resize(&delete.k, max_sectors);
 339                 bch2_cut_back(end, &delete);
 340
 341                 ret = bch2_extent_update(trans, iter, &delete,
 342                                 &disk_res, journal_seq,
 343                                 0, i_sectors_delta);
 344                 bch2_disk_reservation_put(c, &disk_res);
 345 btree_err:
 346                 if (ret == -EINTR) {
 347                         ret2 = ret;
 348                         ret = 0;
 349                 }
 350                 if (ret)
 351                         break;
 352         }
 353
 354         if (bkey_cmp(iter->pos, end) > 0) {
 355                 bch2_btree_iter_set_pos(iter, end);
 356                 ret = bch2_btree_iter_traverse(iter);
 357         }
 358
 359         return ret ?: ret2;
 360 }
 361
 362 int bch2_fpunch(struct bch_fs *c, u64 inum, u64 start, u64 end,
 363                 u64 *journal_seq, s64 *i_sectors_delta)
 364 {
 365         struct btree_trans trans;
 366         struct btree_iter *iter;
 367         int ret = 0;
 368
 369         bch2_trans_init(&trans, c, BTREE_ITER_MAX, 1024);
 370         iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS,
 371                                    POS(inum, start),
 372                                    BTREE_ITER_INTENT);
 373
 374         ret = bch2_fpunch_at(&trans, iter, POS(inum, end),
 375                              journal_seq, i_sectors_delta);
 376         bch2_trans_exit(&trans);
 377
 378         if (ret == -EINTR)
 379                 ret = 0;
 380
 381         return ret;
 382 }
 383
 384 int bch2_write_index_default(struct bch_write_op *op)
 385 {
 386         struct bch_fs *c = op->c;
 387         struct bkey_on_stack sk;
 388         struct keylist *keys = &op->insert_keys;
 389         struct bkey_i *k = bch2_keylist_front(keys);
 390         struct btree_trans trans;
 391         struct btree_iter *iter;
 392         int ret;
 393
 394         bkey_on_stack_init(&sk);
 395         bch2_trans_init(&trans, c, BTREE_ITER_MAX, 1024);
 396
 397         iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS,
 398                                    bkey_start_pos(&k->k),
 399                                    BTREE_ITER_SLOTS|BTREE_ITER_INTENT);
 400
 401         do {
 402                 bch2_trans_begin(&trans);
 403
 404                 k = bch2_keylist_front(keys);
 405
 406                 bkey_on_stack_realloc(&sk, c, k->k.u64s);
 407                 bkey_copy(sk.k, k);
 408                 bch2_cut_front(iter->pos, sk.k);
 409
 410                 ret = bch2_extent_update(&trans, iter, sk.k,
 411                                          &op->res, op_journal_seq(op),
 412                                          op->new_i_size, &op->i_sectors_delta);
 413                 if (ret == -EINTR)
 414                         continue;
 415                 if (ret)
 416                         break;
 417
 418                 if (bkey_cmp(iter->pos, k->k.p) >= 0)
 419                         bch2_keylist_pop_front(keys);
 420         } while (!bch2_keylist_empty(keys));
 421
 422         bch2_trans_exit(&trans);
 423         bkey_on_stack_exit(&sk, c);
 424
 425         return ret;
 426 }
 427
 428 /* Writes */
 429
 430 void bch2_submit_wbio_replicas(struct bch_write_bio *wbio, struct bch_fs *c,
 431                                enum bch_data_type type,
 432                                const struct bkey_i *k)
 433 {
 434         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(bkey_i_to_s_c(k));
 435         const struct bch_extent_ptr *ptr;
 436         struct bch_write_bio *n;
 437         struct bch_dev *ca;
 438
 439         BUG_ON(c->opts.nochanges);
 440
 441         bkey_for_each_ptr(ptrs, ptr) {
 442                 BUG_ON(ptr->dev >= BCH_SB_MEMBERS_MAX ||
 443                        !c->devs[ptr->dev]);
 444
 445                 ca = bch_dev_bkey_exists(c, ptr->dev);
 446
 447                 if (to_entry(ptr + 1) < ptrs.end) {
 448                         n = to_wbio(bio_clone_fast(&wbio->bio, GFP_NOIO,
 449                                                    &ca->replica_set));
 450
 451                         n->bio.bi_end_io        = wbio->bio.bi_end_io;
 452                         n->bio.bi_private       = wbio->bio.bi_private;
 453                         n->parent               = wbio;
 454                         n->split                = true;
 455                         n->bounce               = false;
 456                         n->put_bio              = true;
 457                         n->bio.bi_opf           = wbio->bio.bi_opf;
 458                         bio_inc_remaining(&wbio->bio);
 459                 } else {
 460                         n = wbio;
 461                         n->split                = false;
 462                 }
 463
 464                 n->c                    = c;
 465                 n->dev                  = ptr->dev;
 466                 n->have_ioref           = bch2_dev_get_ioref(ca, WRITE);
 467                 n->submit_time          = local_clock();
 468                 n->bio.bi_iter.bi_sector = ptr->offset;
 469
 470                 if (!journal_flushes_device(ca))
 471                         n->bio.bi_opf |= REQ_FUA;
 472
 473                 if (likely(n->have_ioref)) {
 474                         this_cpu_add(ca->io_done->sectors[WRITE][type],
 475                                      bio_sectors(&n->bio));
 476
 477                         bio_set_dev(&n->bio, ca->disk_sb.bdev);
 478                         submit_bio(&n->bio);
 479                 } else {
 480                         n->bio.bi_status        = BLK_STS_REMOVED;
 481                         bio_endio(&n->bio);
 482                 }
 483         }
 484 }
 485
 486 static void __bch2_write(struct closure *);
 487
 488 static void bch2_write_done(struct closure *cl)
 489 {
 490         struct bch_write_op *op = container_of(cl, struct bch_write_op, cl);
 491         struct bch_fs *c = op->c;
 492
 493         if (!op->error && (op->flags & BCH_WRITE_FLUSH))
 494                 op->error = bch2_journal_error(&c->journal);
 495
 496         if (!(op->flags & BCH_WRITE_NOPUT_RESERVATION))
 497                 bch2_disk_reservation_put(c, &op->res);
 498         percpu_ref_put(&c->writes);
 499         bch2_keylist_free(&op->insert_keys, op->inline_keys);
 500
 501         bch2_time_stats_update(&c->times[BCH_TIME_data_write], op->start_time);
 502
 503         if (op->end_io) {
 504                 EBUG_ON(cl->parent);
 505                 closure_debug_destroy(cl);
 506                 op->end_io(op);
 507         } else {
 508                 closure_return(cl);
 509         }
 510 }
 511
 512 /**
 513  * bch_write_index - after a write, update index to point to new data
 514  */
 515 static void __bch2_write_index(struct bch_write_op *op)
 516 {
 517         struct bch_fs *c = op->c;
 518         struct keylist *keys = &op->insert_keys;
 519         struct bch_extent_ptr *ptr;
 520         struct bkey_i *src, *dst = keys->keys, *n, *k;
 521         unsigned dev;
 522         int ret;
 523
 524         for (src = keys->keys; src != keys->top; src = n) {
 525                 n = bkey_next(src);
 526
 527                 if (bkey_extent_is_direct_data(&src->k)) {
 528                         bch2_bkey_drop_ptrs(bkey_i_to_s(src), ptr,
 529                                             test_bit(ptr->dev, op->failed.d));
 530
 531                         if (!bch2_bkey_nr_ptrs(bkey_i_to_s_c(src))) {
 532                                 ret = -EIO;
 533                                 goto err;
 534                         }
 535                 }
 536
 537                 if (dst != src)
 538                         memmove_u64s_down(dst, src, src->u64s);
 539                 dst = bkey_next(dst);
 540         }
 541
 542         keys->top = dst;
 543
 544         /*
 545          * probably not the ideal place to hook this in, but I don't
 546          * particularly want to plumb io_opts all the way through the btree
 547          * update stack right now
 548          */
 549         for_each_keylist_key(keys, k) {
 550                 bch2_rebalance_add_key(c, bkey_i_to_s_c(k), &op->opts);
 551
 552                 if (bch2_bkey_is_incompressible(bkey_i_to_s_c(k)))
 553                         bch2_check_set_feature(op->c, BCH_FEATURE_incompressible);
 554
 555         }
 556
 557         if (!bch2_keylist_empty(keys)) {
 558                 u64 sectors_start = keylist_sectors(keys);
 559                 int ret = op->index_update_fn(op);
 560
 561                 BUG_ON(ret == -EINTR);
 562                 BUG_ON(keylist_sectors(keys) && !ret);
 563
 564                 op->written += sectors_start - keylist_sectors(keys);
 565
 566                 if (ret) {
 567                         __bcache_io_error(c, "btree IO error %i", ret);
 568                         op->error = ret;
 569                 }
 570         }
 571 out:
 572         /* If some a bucket wasn't written, we can't erasure code it: */
 573         for_each_set_bit(dev, op->failed.d, BCH_SB_MEMBERS_MAX)
 574                 bch2_open_bucket_write_error(c, &op->open_buckets, dev);
 575
 576         bch2_open_buckets_put(c, &op->open_buckets);
 577         return;
 578 err:
 579         keys->top = keys->keys;
 580         op->error = ret;
 581         goto out;
 582 }
 583
 584 static void bch2_write_index(struct closure *cl)
 585 {
 586         struct bch_write_op *op = container_of(cl, struct bch_write_op, cl);
 587         struct bch_fs *c = op->c;
 588
 589         __bch2_write_index(op);
 590
 591         if (!op->error && (op->flags & BCH_WRITE_FLUSH)) {
 592                 bch2_journal_flush_seq_async(&c->journal,
 593                                              *op_journal_seq(op),
 594                                              cl);
 595                 continue_at(cl, bch2_write_done, index_update_wq(op));
 596         } else {
 597                 continue_at_nobarrier(cl, bch2_write_done, NULL);
 598         }
 599 }
 600
 601 static void bch2_write_endio(struct bio *bio)
 602 {
 603         struct closure *cl              = bio->bi_private;
 604         struct bch_write_op *op         = container_of(cl, struct bch_write_op, cl);
 605         struct bch_write_bio *wbio      = to_wbio(bio);
 606         struct bch_write_bio *parent    = wbio->split ? wbio->parent : NULL;
 607         struct bch_fs *c                = wbio->c;
 608         struct bch_dev *ca              = bch_dev_bkey_exists(c, wbio->dev);
 609
 610         if (bch2_dev_io_err_on(bio->bi_status, ca, "data write"))
 611                 set_bit(wbio->dev, op->failed.d);
 612
 613         if (wbio->have_ioref) {
 614                 bch2_latency_acct(ca, wbio->submit_time, WRITE);
 615                 percpu_ref_put(&ca->io_ref);
 616         }
 617
 618         if (wbio->bounce)
 619                 bch2_bio_free_pages_pool(c, bio);
 620
 621         if (wbio->put_bio)
 622                 bio_put(bio);
 623
 624         if (parent)
 625                 bio_endio(&parent->bio);
 626         else if (!(op->flags & BCH_WRITE_SKIP_CLOSURE_PUT))
 627                 closure_put(cl);
 628         else
 629                 continue_at_nobarrier(cl, bch2_write_index, index_update_wq(op));
 630 }
 631
 632 static void init_append_extent(struct bch_write_op *op,
 633                                struct write_point *wp,
 634                                struct bversion version,
 635                                struct bch_extent_crc_unpacked crc)
 636 {
 637         struct bch_fs *c = op->c;
 638         struct bkey_i_extent *e;
 639         struct open_bucket *ob;
 640         unsigned i;
 641
 642         BUG_ON(crc.compressed_size > wp->sectors_free);
 643         wp->sectors_free -= crc.compressed_size;
 644         op->pos.offset += crc.uncompressed_size;
 645
 646         e = bkey_extent_init(op->insert_keys.top);
 647         e->k.p          = op->pos;
 648         e->k.size       = crc.uncompressed_size;
 649         e->k.version    = version;
 650
 651         if (crc.csum_type ||
 652             crc.compression_type ||
 653             crc.nonce)
 654                 bch2_extent_crc_append(&e->k_i, crc);
 655
 656         open_bucket_for_each(c, &wp->ptrs, ob, i) {
 657                 struct bch_dev *ca = bch_dev_bkey_exists(c, ob->ptr.dev);
 658                 union bch_extent_entry *end =
 659                         bkey_val_end(bkey_i_to_s(&e->k_i));
 660
 661                 end->ptr = ob->ptr;
 662                 end->ptr.type = 1 << BCH_EXTENT_ENTRY_ptr;
 663                 end->ptr.cached = !ca->mi.durability ||
 664                         (op->flags & BCH_WRITE_CACHED) != 0;
 665                 end->ptr.offset += ca->mi.bucket_size - ob->sectors_free;
 666
 667                 e->k.u64s++;
 668
 669                 BUG_ON(crc.compressed_size > ob->sectors_free);
 670                 ob->sectors_free -= crc.compressed_size;
 671         }
 672
 673         bch2_keylist_push(&op->insert_keys);
 674 }
 675
 676 static struct bio *bch2_write_bio_alloc(struct bch_fs *c,
 677                                         struct write_point *wp,
 678                                         struct bio *src,
 679                                         bool *page_alloc_failed,
 680                                         void *buf)
 681 {
 682         struct bch_write_bio *wbio;
 683         struct bio *bio;
 684         unsigned output_available =
 685                 min(wp->sectors_free << 9, src->bi_iter.bi_size);
 686         unsigned pages = DIV_ROUND_UP(output_available +
 687                                       (buf
 688                                        ? ((unsigned long) buf & (PAGE_SIZE - 1))
 689                                        : 0), PAGE_SIZE);
 690
 691         bio = bio_alloc_bioset(GFP_NOIO, pages, &c->bio_write);
 692         wbio                    = wbio_init(bio);
 693         wbio->put_bio           = true;
 694         /* copy WRITE_SYNC flag */
 695         wbio->bio.bi_opf        = src->bi_opf;
 696
 697         if (buf) {
 698                 bch2_bio_map(bio, buf, output_available);
 699                 return bio;
 700         }
 701
 702         wbio->bounce            = true;
 703
 704         /*
 705          * We can't use mempool for more than c->sb.encoded_extent_max
 706          * worth of pages, but we'd like to allocate more if we can:
 707          */
 708         bch2_bio_alloc_pages_pool(c, bio,
 709                                   min_t(unsigned, output_available,
 710                                         c->sb.encoded_extent_max << 9));
 711
 712         if (bio->bi_iter.bi_size < output_available)
 713                 *page_alloc_failed =
 714                         bch2_bio_alloc_pages(bio,
 715                                              output_available -
 716                                              bio->bi_iter.bi_size,
 717                                              GFP_NOFS) != 0;
 718
 719         return bio;
 720 }
 721
 722 static int bch2_write_rechecksum(struct bch_fs *c,
 723                                  struct bch_write_op *op,
 724                                  unsigned new_csum_type)
 725 {
 726         struct bio *bio = &op->wbio.bio;
 727         struct bch_extent_crc_unpacked new_crc;
 728         int ret;
 729
 730         /* bch2_rechecksum_bio() can't encrypt or decrypt data: */
 731
 732         if (bch2_csum_type_is_encryption(op->crc.csum_type) !=
 733             bch2_csum_type_is_encryption(new_csum_type))
 734                 new_csum_type = op->crc.csum_type;
 735
 736         ret = bch2_rechecksum_bio(c, bio, op->version, op->crc,
 737                                   NULL, &new_crc,
 738                                   op->crc.offset, op->crc.live_size,
 739                                   new_csum_type);
 740         if (ret)
 741                 return ret;
 742
 743         bio_advance(bio, op->crc.offset << 9);
 744         bio->bi_iter.bi_size = op->crc.live_size << 9;
 745         op->crc = new_crc;
 746         return 0;
 747 }
 748
 749 static int bch2_write_decrypt(struct bch_write_op *op)
 750 {
 751         struct bch_fs *c = op->c;
 752         struct nonce nonce = extent_nonce(op->version, op->crc);
 753         struct bch_csum csum;
 754
 755         if (!bch2_csum_type_is_encryption(op->crc.csum_type))
 756                 return 0;
 757
 758         /*
 759          * If we need to decrypt data in the write path, we'll no longer be able
 760          * to verify the existing checksum (poly1305 mac, in this case) after
 761          * it's decrypted - this is the last point we'll be able to reverify the
 762          * checksum:
 763          */
 764         csum = bch2_checksum_bio(c, op->crc.csum_type, nonce, &op->wbio.bio);
 765         if (bch2_crc_cmp(op->crc.csum, csum))
 766                 return -EIO;
 767
 768         bch2_encrypt_bio(c, op->crc.csum_type, nonce, &op->wbio.bio);
 769         op->crc.csum_type = 0;
 770         op->crc.csum = (struct bch_csum) { 0, 0 };
 771         return 0;
 772 }
 773
 774 static enum prep_encoded_ret {
 775         PREP_ENCODED_OK,
 776         PREP_ENCODED_ERR,
 777         PREP_ENCODED_CHECKSUM_ERR,
 778         PREP_ENCODED_DO_WRITE,
 779 } bch2_write_prep_encoded_data(struct bch_write_op *op, struct write_point *wp)
 780 {
 781         struct bch_fs *c = op->c;
 782         struct bio *bio = &op->wbio.bio;
 783
 784         if (!(op->flags & BCH_WRITE_DATA_ENCODED))
 785                 return PREP_ENCODED_OK;
 786
 787         BUG_ON(bio_sectors(bio) != op->crc.compressed_size);
 788
 789         /* Can we just write the entire extent as is? */
 790         if (op->crc.uncompressed_size == op->crc.live_size &&
 791             op->crc.compressed_size <= wp->sectors_free &&
 792             (op->crc.compression_type == op->compression_type ||
 793              op->incompressible)) {
 794                 if (!crc_is_compressed(op->crc) &&
 795                     op->csum_type != op->crc.csum_type &&
 796                     bch2_write_rechecksum(c, op, op->csum_type))
 797                         return PREP_ENCODED_CHECKSUM_ERR;
 798
 799                 return PREP_ENCODED_DO_WRITE;
 800         }
 801
 802         /*
 803          * If the data is compressed and we couldn't write the entire extent as
 804          * is, we have to decompress it:
 805          */
 806         if (crc_is_compressed(op->crc)) {
 807                 struct bch_csum csum;
 808
 809                 if (bch2_write_decrypt(op))
 810                         return PREP_ENCODED_CHECKSUM_ERR;
 811
 812                 /* Last point we can still verify checksum: */
 813                 csum = bch2_checksum_bio(c, op->crc.csum_type,
 814                                          extent_nonce(op->version, op->crc),
 815                                          bio);
 816                 if (bch2_crc_cmp(op->crc.csum, csum))
 817                         return PREP_ENCODED_CHECKSUM_ERR;
 818
 819                 if (bch2_bio_uncompress_inplace(c, bio, &op->crc))
 820                         return PREP_ENCODED_ERR;
 821         }
 822
 823         /*
 824          * No longer have compressed data after this point - data might be
 825          * encrypted:
 826          */
 827
 828         /*
 829          * If the data is checksummed and we're only writing a subset,
 830          * rechecksum and adjust bio to point to currently live data:
 831          */
 832         if ((op->crc.live_size != op->crc.uncompressed_size ||
 833              op->crc.csum_type != op->csum_type) &&
 834             bch2_write_rechecksum(c, op, op->csum_type))
 835                 return PREP_ENCODED_CHECKSUM_ERR;
 836
 837         /*
 838          * If we want to compress the data, it has to be decrypted:
 839          */
 840         if ((op->compression_type ||
 841              bch2_csum_type_is_encryption(op->crc.csum_type) !=
 842              bch2_csum_type_is_encryption(op->csum_type)) &&
 843             bch2_write_decrypt(op))
 844                 return PREP_ENCODED_CHECKSUM_ERR;
 845
 846         return PREP_ENCODED_OK;
 847 }
 848
 849 static int bch2_write_extent(struct bch_write_op *op, struct write_point *wp,
 850                              struct bio **_dst)
 851 {
 852         struct bch_fs *c = op->c;
 853         struct bio *src = &op->wbio.bio, *dst = src;
 854         struct bvec_iter saved_iter;
 855         void *ec_buf;
 856         struct bpos ec_pos = op->pos;
 857         unsigned total_output = 0, total_input = 0;
 858         bool bounce = false;
 859         bool page_alloc_failed = false;
 860         int ret, more = 0;
 861
 862         BUG_ON(!bio_sectors(src));
 863
 864         ec_buf = bch2_writepoint_ec_buf(c, wp);
 865
 866         switch (bch2_write_prep_encoded_data(op, wp)) {
 867         case PREP_ENCODED_OK:
 868                 break;
 869         case PREP_ENCODED_ERR:
 870                 ret = -EIO;
 871                 goto err;
 872         case PREP_ENCODED_CHECKSUM_ERR:
 873                 BUG();
 874                 goto csum_err;
 875         case PREP_ENCODED_DO_WRITE:
 876                 /* XXX look for bug here */
 877                 if (ec_buf) {
 878                         dst = bch2_write_bio_alloc(c, wp, src,
 879                                                    &page_alloc_failed,
 880                                                    ec_buf);
 881                         bio_copy_data(dst, src);
 882                         bounce = true;
 883                 }
 884                 init_append_extent(op, wp, op->version, op->crc);
 885                 goto do_write;
 886         }
 887
 888         if (ec_buf ||
 889             op->compression_type ||
 890             (op->csum_type &&
 891              !(op->flags & BCH_WRITE_PAGES_STABLE)) ||
 892             (bch2_csum_type_is_encryption(op->csum_type) &&
 893              !(op->flags & BCH_WRITE_PAGES_OWNED))) {
 894                 dst = bch2_write_bio_alloc(c, wp, src,
 895                                            &page_alloc_failed,
 896                                            ec_buf);
 897                 bounce = true;
 898         }
 899
 900         saved_iter = dst->bi_iter;
 901
 902         do {
 903                 struct bch_extent_crc_unpacked crc =
 904                         (struct bch_extent_crc_unpacked) { 0 };
 905                 struct bversion version = op->version;
 906                 size_t dst_len, src_len;
 907
 908                 if (page_alloc_failed &&
 909                     bio_sectors(dst) < wp->sectors_free &&
 910                     bio_sectors(dst) < c->sb.encoded_extent_max)
 911                         break;
 912
 913                 BUG_ON(op->compression_type &&
 914                        (op->flags & BCH_WRITE_DATA_ENCODED) &&
 915                        bch2_csum_type_is_encryption(op->crc.csum_type));
 916                 BUG_ON(op->compression_type && !bounce);
 917
 918                 crc.compression_type = op->incompressible
 919                         ? BCH_COMPRESSION_TYPE_incompressible
 920                         : op->compression_type
 921                         ? bch2_bio_compress(c, dst, &dst_len, src, &src_len,
 922                                             op->compression_type)
 923                         : 0;
 924                 if (!crc_is_compressed(crc)) {
 925                         dst_len = min(dst->bi_iter.bi_size, src->bi_iter.bi_size);
 926                         dst_len = min_t(unsigned, dst_len, wp->sectors_free << 9);
 927
 928                         if (op->csum_type)
 929                                 dst_len = min_t(unsigned, dst_len,
 930                                                 c->sb.encoded_extent_max << 9);
 931
 932                         if (bounce) {
 933                                 swap(dst->bi_iter.bi_size, dst_len);
 934                                 bio_copy_data(dst, src);
 935                                 swap(dst->bi_iter.bi_size, dst_len);
 936                         }
 937
 938                         src_len = dst_len;
 939                 }
 940
 941                 BUG_ON(!src_len || !dst_len);
 942
 943                 if (bch2_csum_type_is_encryption(op->csum_type)) {
 944                         if (bversion_zero(version)) {
 945                                 version.lo = atomic64_inc_return(&c->key_version);
 946                         } else {
 947                                 crc.nonce = op->nonce;
 948                                 op->nonce += src_len >> 9;
 949                         }
 950                 }
 951
 952                 if ((op->flags & BCH_WRITE_DATA_ENCODED) &&
 953                     !crc_is_compressed(crc) &&
 954                     bch2_csum_type_is_encryption(op->crc.csum_type) ==
 955                     bch2_csum_type_is_encryption(op->csum_type)) {
 956                         /*
 957                          * Note: when we're using rechecksum(), we need to be
 958                          * checksumming @src because it has all the data our
 959                          * existing checksum covers - if we bounced (because we
 960                          * were trying to compress), @dst will only have the
 961                          * part of the data the new checksum will cover.
 962                          *
 963                          * But normally we want to be checksumming post bounce,
 964                          * because part of the reason for bouncing is so the
 965                          * data can't be modified (by userspace) while it's in
 966                          * flight.
 967                          */
 968                         if (bch2_rechecksum_bio(c, src, version, op->crc,
 969                                         &crc, &op->crc,
 970                                         src_len >> 9,
 971                                         bio_sectors(src) - (src_len >> 9),
 972                                         op->csum_type))
 973                                 goto csum_err;
 974                 } else {
 975                         if ((op->flags & BCH_WRITE_DATA_ENCODED) &&
 976                             bch2_rechecksum_bio(c, src, version, op->crc,
 977                                         NULL, &op->crc,
 978                                         src_len >> 9,
 979                                         bio_sectors(src) - (src_len >> 9),
 980                                         op->crc.csum_type))
 981                                 goto csum_err;
 982
 983                         crc.compressed_size     = dst_len >> 9;
 984                         crc.uncompressed_size   = src_len >> 9;
 985                         crc.live_size           = src_len >> 9;
 986
 987                         swap(dst->bi_iter.bi_size, dst_len);
 988                         bch2_encrypt_bio(c, op->csum_type,
 989                                          extent_nonce(version, crc), dst);
 990                         crc.csum = bch2_checksum_bio(c, op->csum_type,
 991                                          extent_nonce(version, crc), dst);
 992                         crc.csum_type = op->csum_type;
 993                         swap(dst->bi_iter.bi_size, dst_len);
 994                 }
 995
 996                 init_append_extent(op, wp, version, crc);
 997
 998                 if (dst != src)
 999                         bio_advance(dst, dst_len);
1000                 bio_advance(src, src_len);
1001                 total_output    += dst_len;
1002                 total_input     += src_len;
1003         } while (dst->bi_iter.bi_size &&
1004                  src->bi_iter.bi_size &&
1005                  wp->sectors_free &&
1006                  !bch2_keylist_realloc(&op->insert_keys,
1007                                       op->inline_keys,
1008                                       ARRAY_SIZE(op->inline_keys),
1009                                       BKEY_EXTENT_U64s_MAX));
1010
1011         more = src->bi_iter.bi_size != 0;
1012
1013         dst->bi_iter = saved_iter;
1014
1015         if (dst == src && more) {
1016                 BUG_ON(total_output != total_input);
1017
1018                 dst = bio_split(src, total_input >> 9,
1019                                 GFP_NOIO, &c->bio_write);
1020                 wbio_init(dst)->put_bio = true;
1021                 /* copy WRITE_SYNC flag */
1022                 dst->bi_opf             = src->bi_opf;
1023         }
1024
1025         dst->bi_iter.bi_size = total_output;
1026 do_write:
1027         /* might have done a realloc... */
1028         bch2_ec_add_backpointer(c, wp, ec_pos, total_input >> 9);
1029
1030         *_dst = dst;
1031         return more;
1032 csum_err:
1033         bch_err(c, "error verifying existing checksum while "
1034                 "rewriting existing data (memory corruption?)");
1035         ret = -EIO;
1036 err:
1037         if (to_wbio(dst)->bounce)
1038                 bch2_bio_free_pages_pool(c, dst);
1039         if (to_wbio(dst)->put_bio)
1040                 bio_put(dst);
1041
1042         return ret;
1043 }
1044
1045 static void __bch2_write(struct closure *cl)
1046 {
1047         struct bch_write_op *op = container_of(cl, struct bch_write_op, cl);
1048         struct bch_fs *c = op->c;
1049         struct write_point *wp;
1050         struct bio *bio;
1051         bool skip_put = true;
1052         int ret;
1053 again:
1054         memset(&op->failed, 0, sizeof(op->failed));
1055
1056         do {
1057                 struct bkey_i *key_to_write;
1058                 unsigned key_to_write_offset = op->insert_keys.top_p -
1059                         op->insert_keys.keys_p;
1060
1061                 /* +1 for possible cache device: */
1062                 if (op->open_buckets.nr + op->nr_replicas + 1 >
1063                     ARRAY_SIZE(op->open_buckets.v))
1064                         goto flush_io;
1065
1066                 if (bch2_keylist_realloc(&op->insert_keys,
1067                                         op->inline_keys,
1068                                         ARRAY_SIZE(op->inline_keys),
1069                                         BKEY_EXTENT_U64s_MAX))
1070                         goto flush_io;
1071
1072                 wp = bch2_alloc_sectors_start(c,
1073                         op->target,
1074                         op->opts.erasure_code,
1075                         op->write_point,
1076                         &op->devs_have,
1077                         op->nr_replicas,
1078                         op->nr_replicas_required,
1079                         op->alloc_reserve,
1080                         op->flags,
1081                         (op->flags & BCH_WRITE_ALLOC_NOWAIT) ? NULL : cl);
1082                 EBUG_ON(!wp);
1083
1084                 if (unlikely(IS_ERR(wp))) {
1085                         if (unlikely(PTR_ERR(wp) != -EAGAIN)) {
1086                                 ret = PTR_ERR(wp);
1087                                 goto err;
1088                         }
1089
1090                         goto flush_io;
1091                 }
1092
1093                 bch2_open_bucket_get(c, wp, &op->open_buckets);
1094                 ret = bch2_write_extent(op, wp, &bio);
1095                 bch2_alloc_sectors_done(c, wp);
1096
1097                 if (ret < 0)
1098                         goto err;
1099
1100                 if (ret)
1101                         skip_put = false;
1102
1103                 bio->bi_end_io  = bch2_write_endio;
1104                 bio->bi_private = &op->cl;
1105                 bio->bi_opf |= REQ_OP_WRITE;
1106
1107                 if (!skip_put)
1108                         closure_get(bio->bi_private);
1109                 else
1110                         op->flags |= BCH_WRITE_SKIP_CLOSURE_PUT;
1111
1112                 key_to_write = (void *) (op->insert_keys.keys_p +
1113                                          key_to_write_offset);
1114
1115                 bch2_submit_wbio_replicas(to_wbio(bio), c, BCH_DATA_USER,
1116                                           key_to_write);
1117         } while (ret);
1118
1119         if (!skip_put)
1120                 continue_at(cl, bch2_write_index, index_update_wq(op));
1121         return;
1122 err:
1123         op->error = ret;
1124
1125         continue_at(cl, bch2_write_index, index_update_wq(op));
1126         return;
1127 flush_io:
1128         closure_sync(cl);
1129
1130         if (!bch2_keylist_empty(&op->insert_keys)) {
1131                 __bch2_write_index(op);
1132
1133                 if (op->error) {
1134                         continue_at_nobarrier(cl, bch2_write_done, NULL);
1135                         return;
1136                 }
1137         }
1138
1139         goto again;
1140 }
1141
1142 static void bch2_write_data_inline(struct bch_write_op *op, unsigned data_len)
1143 {
1144         struct closure *cl = &op->cl;
1145         struct bio *bio = &op->wbio.bio;
1146         struct bvec_iter iter;
1147         struct bkey_i_inline_data *id;
1148         unsigned sectors;
1149         int ret;
1150
1151         bch2_check_set_feature(op->c, BCH_FEATURE_inline_data);
1152
1153         ret = bch2_keylist_realloc(&op->insert_keys, op->inline_keys,
1154                                    ARRAY_SIZE(op->inline_keys),
1155                                    BKEY_U64s + DIV_ROUND_UP(data_len, 8));
1156         if (ret) {
1157                 op->error = ret;
1158                 goto err;
1159         }
1160
1161         sectors = bio_sectors(bio);
1162         op->pos.offset += sectors;
1163
1164         id = bkey_inline_data_init(op->insert_keys.top);
1165         id->k.p         = op->pos;
1166         id->k.version   = op->version;
1167         id->k.size      = sectors;
1168
1169         iter = bio->bi_iter;
1170         iter.bi_size = data_len;
1171         memcpy_from_bio(id->v.data, bio, iter);
1172
1173         while (data_len & 7)
1174                 id->v.data[data_len++] = '\0';
1175         set_bkey_val_bytes(&id->k, data_len);
1176         bch2_keylist_push(&op->insert_keys);
1177
1178         op->flags |= BCH_WRITE_WROTE_DATA_INLINE;
1179         continue_at_nobarrier(cl, bch2_write_index, NULL);
1180         return;
1181 err:
1182         bch2_write_done(&op->cl);
1183 }
1184
1185 /**
1186  * bch_write - handle a write to a cache device or flash only volume
1187  *
1188  * This is the starting point for any data to end up in a cache device; it could
1189  * be from a normal write, or a writeback write, or a write to a flash only
1190  * volume - it's also used by the moving garbage collector to compact data in
1191  * mostly empty buckets.
1192  *
1193  * It first writes the data to the cache, creating a list of keys to be inserted
1194  * (if the data won't fit in a single open bucket, there will be multiple keys);
1195  * after the data is written it calls bch_journal, and after the keys have been
1196  * added to the next journal write they're inserted into the btree.
1197  *
1198  * If op->discard is true, instead of inserting the data it invalidates the
1199  * region of the cache represented by op->bio and op->inode.
1200  */
1201 void bch2_write(struct closure *cl)
1202 {
1203         struct bch_write_op *op = container_of(cl, struct bch_write_op, cl);
1204         struct bio *bio = &op->wbio.bio;
1205         struct bch_fs *c = op->c;
1206         unsigned data_len;
1207
1208         BUG_ON(!op->nr_replicas);
1209         BUG_ON(!op->write_point.v);
1210         BUG_ON(!bkey_cmp(op->pos, POS_MAX));
1211
1212         op->start_time = local_clock();
1213         bch2_keylist_init(&op->insert_keys, op->inline_keys);
1214         wbio_init(bio)->put_bio = false;
1215
1216         if (bio_sectors(bio) & (c->opts.block_size - 1)) {
1217                 __bcache_io_error(c, "misaligned write");
1218                 op->error = -EIO;
1219                 goto err;
1220         }
1221
1222         if (c->opts.nochanges ||
1223             !percpu_ref_tryget(&c->writes)) {
1224                 if (!(op->flags & BCH_WRITE_FROM_INTERNAL))
1225                         __bcache_io_error(c, "read only");
1226                 op->error = -EROFS;
1227                 goto err;
1228         }
1229
1230         bch2_increment_clock(c, bio_sectors(bio), WRITE);
1231
1232         data_len = min_t(u64, bio->bi_iter.bi_size,
1233                          op->new_i_size - (op->pos.offset << 9));
1234
1235         if (c->opts.inline_data &&
1236             data_len <= min(block_bytes(c) / 2, 1024U)) {
1237                 bch2_write_data_inline(op, data_len);
1238                 return;
1239         }
1240
1241         continue_at_nobarrier(cl, __bch2_write, NULL);
1242         return;
1243 err:
1244         if (!(op->flags & BCH_WRITE_NOPUT_RESERVATION))
1245                 bch2_disk_reservation_put(c, &op->res);
1246
1247         if (op->end_io) {
1248                 EBUG_ON(cl->parent);
1249                 closure_debug_destroy(cl);
1250                 op->end_io(op);
1251         } else {
1252                 closure_return(cl);
1253         }
1254 }
1255
1256 /* Cache promotion on read */
1257
1258 struct promote_op {
1259         struct closure          cl;
1260         struct rcu_head         rcu;
1261         u64                     start_time;
1262
1263         struct rhash_head       hash;
1264         struct bpos             pos;
1265
1266         struct migrate_write    write;
1267         struct bio_vec          bi_inline_vecs[0]; /* must be last */
1268 };
1269
1270 static const struct rhashtable_params bch_promote_params = {
1271         .head_offset    = offsetof(struct promote_op, hash),
1272         .key_offset     = offsetof(struct promote_op, pos),
1273         .key_len        = sizeof(struct bpos),
1274 };
1275
1276 static inline bool should_promote(struct bch_fs *c, struct bkey_s_c k,
1277                                   struct bpos pos,
1278                                   struct bch_io_opts opts,
1279                                   unsigned flags)
1280 {
1281         if (!(flags & BCH_READ_MAY_PROMOTE))
1282                 return false;
1283
1284         if (!opts.promote_target)
1285                 return false;
1286
1287         if (bch2_bkey_has_target(c, k, opts.promote_target))
1288                 return false;
1289
1290         if (bch2_target_congested(c, opts.promote_target)) {
1291                 /* XXX trace this */
1292                 return false;
1293         }
1294
1295         if (rhashtable_lookup_fast(&c->promote_table, &pos,
1296                                    bch_promote_params))
1297                 return false;
1298
1299         return true;
1300 }
1301
1302 static void promote_free(struct bch_fs *c, struct promote_op *op)
1303 {
1304         int ret;
1305
1306         ret = rhashtable_remove_fast(&c->promote_table, &op->hash,
1307                                      bch_promote_params);
1308         BUG_ON(ret);
1309         percpu_ref_put(&c->writes);
1310         kfree_rcu(op, rcu);
1311 }
1312
1313 static void promote_done(struct closure *cl)
1314 {
1315         struct promote_op *op =
1316                 container_of(cl, struct promote_op, cl);
1317         struct bch_fs *c = op->write.op.c;
1318
1319         bch2_time_stats_update(&c->times[BCH_TIME_data_promote],
1320                                op->start_time);
1321
1322         bch2_bio_free_pages_pool(c, &op->write.op.wbio.bio);
1323         promote_free(c, op);
1324 }
1325
1326 static void promote_start(struct promote_op *op, struct bch_read_bio *rbio)
1327 {
1328         struct bch_fs *c = rbio->c;
1329         struct closure *cl = &op->cl;
1330         struct bio *bio = &op->write.op.wbio.bio;
1331
1332         trace_promote(&rbio->bio);
1333
1334         /* we now own pages: */
1335         BUG_ON(!rbio->bounce);
1336         BUG_ON(rbio->bio.bi_vcnt > bio->bi_max_vecs);
1337
1338         memcpy(bio->bi_io_vec, rbio->bio.bi_io_vec,
1339                sizeof(struct bio_vec) * rbio->bio.bi_vcnt);
1340         swap(bio->bi_vcnt, rbio->bio.bi_vcnt);
1341
1342         bch2_migrate_read_done(&op->write, rbio);
1343
1344         closure_init(cl, NULL);
1345         closure_call(&op->write.op.cl, bch2_write, c->wq, cl);
1346         closure_return_with_destructor(cl, promote_done);
1347 }
1348
1349 static struct promote_op *__promote_alloc(struct bch_fs *c,
1350                                           enum btree_id btree_id,
1351                                           struct bkey_s_c k,
1352                                           struct bpos pos,
1353                                           struct extent_ptr_decoded *pick,
1354                                           struct bch_io_opts opts,
1355                                           unsigned sectors,
1356                                           struct bch_read_bio **rbio)
1357 {
1358         struct promote_op *op = NULL;
1359         struct bio *bio;
1360         unsigned pages = DIV_ROUND_UP(sectors, PAGE_SECTORS);
1361         int ret;
1362
1363         if (!percpu_ref_tryget(&c->writes))
1364                 return NULL;
1365
1366         op = kzalloc(sizeof(*op) + sizeof(struct bio_vec) * pages, GFP_NOIO);
1367         if (!op)
1368                 goto err;
1369
1370         op->start_time = local_clock();
1371         op->pos = pos;
1372
1373         /*
1374          * We don't use the mempool here because extents that aren't
1375          * checksummed or compressed can be too big for the mempool:
1376          */
1377         *rbio = kzalloc(sizeof(struct bch_read_bio) +
1378                         sizeof(struct bio_vec) * pages,
1379                         GFP_NOIO);
1380         if (!*rbio)
1381                 goto err;
1382
1383         rbio_init(&(*rbio)->bio, opts);
1384         bio_init(&(*rbio)->bio, (*rbio)->bio.bi_inline_vecs, pages);
1385
1386         if (bch2_bio_alloc_pages(&(*rbio)->bio, sectors << 9,
1387                                  GFP_NOIO))
1388                 goto err;
1389
1390         (*rbio)->bounce         = true;
1391         (*rbio)->split          = true;
1392         (*rbio)->kmalloc        = true;
1393
1394         if (rhashtable_lookup_insert_fast(&c->promote_table, &op->hash,
1395                                           bch_promote_params))
1396                 goto err;
1397
1398         bio = &op->write.op.wbio.bio;
1399         bio_init(bio, bio->bi_inline_vecs, pages);
1400
1401         ret = bch2_migrate_write_init(c, &op->write,
1402                         writepoint_hashed((unsigned long) current),
1403                         opts,
1404                         DATA_PROMOTE,
1405                         (struct data_opts) {
1406                                 .target = opts.promote_target
1407                         },
1408                         btree_id, k);
1409         BUG_ON(ret);
1410
1411         return op;
1412 err:
1413         if (*rbio)
1414                 bio_free_pages(&(*rbio)->bio);
1415         kfree(*rbio);
1416         *rbio = NULL;
1417         kfree(op);
1418         percpu_ref_put(&c->writes);
1419         return NULL;
1420 }
1421
1422 noinline
1423 static struct promote_op *promote_alloc(struct bch_fs *c,
1424                                                struct bvec_iter iter,
1425                                                struct bkey_s_c k,
1426                                                struct extent_ptr_decoded *pick,
1427                                                struct bch_io_opts opts,
1428                                                unsigned flags,
1429                                                struct bch_read_bio **rbio,
1430                                                bool *bounce,
1431                                                bool *read_full)
1432 {
1433         bool promote_full = *read_full || READ_ONCE(c->promote_whole_extents);
1434         /* data might have to be decompressed in the write path: */
1435         unsigned sectors = promote_full
1436                 ? max(pick->crc.compressed_size, pick->crc.live_size)
1437                 : bvec_iter_sectors(iter);
1438         struct bpos pos = promote_full
1439                 ? bkey_start_pos(k.k)
1440                 : POS(k.k->p.inode, iter.bi_sector);
1441         struct promote_op *promote;
1442
1443         if (!should_promote(c, k, pos, opts, flags))
1444                 return NULL;
1445
1446         promote = __promote_alloc(c,
1447                                   k.k->type == KEY_TYPE_reflink_v
1448                                   ? BTREE_ID_REFLINK
1449                                   : BTREE_ID_EXTENTS,
1450                                   k, pos, pick, opts, sectors, rbio);
1451         if (!promote)
1452                 return NULL;
1453
1454         *bounce         = true;
1455         *read_full      = promote_full;
1456         return promote;
1457 }
1458
1459 /* Read */
1460
1461 #define READ_RETRY_AVOID        1
1462 #define READ_RETRY              2
1463 #define READ_ERR                3
1464
1465 enum rbio_context {
1466         RBIO_CONTEXT_NULL,
1467         RBIO_CONTEXT_HIGHPRI,
1468         RBIO_CONTEXT_UNBOUND,
1469 };
1470
1471 static inline struct bch_read_bio *
1472 bch2_rbio_parent(struct bch_read_bio *rbio)
1473 {
1474         return rbio->split ? rbio->parent : rbio;
1475 }
1476
1477 __always_inline
1478 static void bch2_rbio_punt(struct bch_read_bio *rbio, work_func_t fn,
1479                            enum rbio_context context,
1480                            struct workqueue_struct *wq)
1481 {
1482         if (context <= rbio->context) {
1483                 fn(&rbio->work);
1484         } else {
1485                 rbio->work.func         = fn;
1486                 rbio->context           = context;
1487                 queue_work(wq, &rbio->work);
1488         }
1489 }
1490
1491 static inline struct bch_read_bio *bch2_rbio_free(struct bch_read_bio *rbio)
1492 {
1493         BUG_ON(rbio->bounce && !rbio->split);
1494
1495         if (rbio->promote)
1496                 promote_free(rbio->c, rbio->promote);
1497         rbio->promote = NULL;
1498
1499         if (rbio->bounce)
1500                 bch2_bio_free_pages_pool(rbio->c, &rbio->bio);
1501
1502         if (rbio->split) {
1503                 struct bch_read_bio *parent = rbio->parent;
1504
1505                 if (rbio->kmalloc)
1506                         kfree(rbio);
1507                 else
1508                         bio_put(&rbio->bio);
1509
1510                 rbio = parent;
1511         }
1512
1513         return rbio;
1514 }
1515
1516 /*
1517  * Only called on a top level bch_read_bio to complete an entire read request,
1518  * not a split:
1519  */
1520 static void bch2_rbio_done(struct bch_read_bio *rbio)
1521 {
1522         if (rbio->start_time)
1523                 bch2_time_stats_update(&rbio->c->times[BCH_TIME_data_read],
1524                                        rbio->start_time);
1525         bio_endio(&rbio->bio);
1526 }
1527
1528 static void bch2_read_retry_nodecode(struct bch_fs *c, struct bch_read_bio *rbio,
1529                                      struct bvec_iter bvec_iter, u64 inode,
1530                                      struct bch_io_failures *failed,
1531                                      unsigned flags)
1532 {
1533         struct btree_trans trans;
1534         struct btree_iter *iter;
1535         struct bkey_on_stack sk;
1536         struct bkey_s_c k;
1537         int ret;
1538
1539         flags &= ~BCH_READ_LAST_FRAGMENT;
1540         flags |= BCH_READ_MUST_CLONE;
1541
1542         bkey_on_stack_init(&sk);
1543         bch2_trans_init(&trans, c, 0, 0);
1544
1545         iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS,
1546                                    rbio->pos, BTREE_ITER_SLOTS);
1547 retry:
1548         rbio->bio.bi_status = 0;
1549
1550         k = bch2_btree_iter_peek_slot(iter);
1551         if (bkey_err(k))
1552                 goto err;
1553
1554         bkey_on_stack_reassemble(&sk, c, k);
1555         k = bkey_i_to_s_c(sk.k);
1556         bch2_trans_unlock(&trans);
1557
1558         if (!bch2_bkey_matches_ptr(c, k,
1559                                    rbio->pick.ptr,
1560                                    rbio->pos.offset -
1561                                    rbio->pick.crc.offset)) {
1562                 /* extent we wanted to read no longer exists: */
1563                 rbio->hole = true;
1564                 goto out;
1565         }
1566
1567         ret = __bch2_read_extent(c, rbio, bvec_iter, k, 0, failed, flags);
1568         if (ret == READ_RETRY)
1569                 goto retry;
1570         if (ret)
1571                 goto err;
1572 out:
1573         bch2_rbio_done(rbio);
1574         bch2_trans_exit(&trans);
1575         bkey_on_stack_exit(&sk, c);
1576         return;
1577 err:
1578         rbio->bio.bi_status = BLK_STS_IOERR;
1579         goto out;
1580 }
1581
1582 static void bch2_read_retry(struct bch_fs *c, struct bch_read_bio *rbio,
1583                             struct bvec_iter bvec_iter, u64 inode,
1584                             struct bch_io_failures *failed, unsigned flags)
1585 {
1586         struct btree_trans trans;
1587         struct btree_iter *iter;
1588         struct bkey_on_stack sk;
1589         struct bkey_s_c k;
1590         int ret;
1591
1592         flags &= ~BCH_READ_LAST_FRAGMENT;
1593         flags |= BCH_READ_MUST_CLONE;
1594
1595         bkey_on_stack_init(&sk);
1596         bch2_trans_init(&trans, c, 0, 0);
1597 retry:
1598         bch2_trans_begin(&trans);
1599
1600         for_each_btree_key(&trans, iter, BTREE_ID_EXTENTS,
1601                            POS(inode, bvec_iter.bi_sector),
1602                            BTREE_ITER_SLOTS, k, ret) {
1603                 unsigned bytes, sectors, offset_into_extent;
1604
1605                 bkey_on_stack_reassemble(&sk, c, k);
1606                 k = bkey_i_to_s_c(sk.k);
1607
1608                 offset_into_extent = iter->pos.offset -
1609                         bkey_start_offset(k.k);
1610                 sectors = k.k->size - offset_into_extent;
1611
1612                 ret = bch2_read_indirect_extent(&trans,
1613                                         &offset_into_extent, sk.k);
1614                 if (ret)
1615                         break;
1616
1617                 sectors = min(sectors, k.k->size - offset_into_extent);
1618
1619                 bch2_trans_unlock(&trans);
1620
1621                 bytes = min(sectors, bvec_iter_sectors(bvec_iter)) << 9;
1622                 swap(bvec_iter.bi_size, bytes);
1623
1624                 ret = __bch2_read_extent(c, rbio, bvec_iter, k,
1625                                 offset_into_extent, failed, flags);
1626                 switch (ret) {
1627                 case READ_RETRY:
1628                         goto retry;
1629                 case READ_ERR:
1630                         goto err;
1631                 };
1632
1633                 if (bytes == bvec_iter.bi_size)
1634                         goto out;
1635
1636                 swap(bvec_iter.bi_size, bytes);
1637                 bio_advance_iter(&rbio->bio, &bvec_iter, bytes);
1638         }
1639
1640         if (ret == -EINTR)
1641                 goto retry;
1642         /*
1643          * If we get here, it better have been because there was an error
1644          * reading a btree node
1645          */
1646         BUG_ON(!ret);
1647         __bcache_io_error(c, "btree IO error: %i", ret);
1648 err:
1649         rbio->bio.bi_status = BLK_STS_IOERR;
1650 out:
1651         bch2_trans_exit(&trans);
1652         bkey_on_stack_exit(&sk, c);
1653         bch2_rbio_done(rbio);
1654 }
1655
1656 static void bch2_rbio_retry(struct work_struct *work)
1657 {
1658         struct bch_read_bio *rbio =
1659                 container_of(work, struct bch_read_bio, work);
1660         struct bch_fs *c        = rbio->c;
1661         struct bvec_iter iter   = rbio->bvec_iter;
1662         unsigned flags          = rbio->flags;
1663         u64 inode               = rbio->pos.inode;
1664         struct bch_io_failures failed = { .nr = 0 };
1665
1666         trace_read_retry(&rbio->bio);
1667
1668         if (rbio->retry == READ_RETRY_AVOID)
1669                 bch2_mark_io_failure(&failed, &rbio->pick);
1670
1671         rbio->bio.bi_status = 0;
1672
1673         rbio = bch2_rbio_free(rbio);
1674
1675         flags |= BCH_READ_IN_RETRY;
1676         flags &= ~BCH_READ_MAY_PROMOTE;
1677
1678         if (flags & BCH_READ_NODECODE)
1679                 bch2_read_retry_nodecode(c, rbio, iter, inode, &failed, flags);
1680         else
1681                 bch2_read_retry(c, rbio, iter, inode, &failed, flags);
1682 }
1683
1684 static void bch2_rbio_error(struct bch_read_bio *rbio, int retry,
1685                             blk_status_t error)
1686 {
1687         rbio->retry = retry;
1688
1689         if (rbio->flags & BCH_READ_IN_RETRY)
1690                 return;
1691
1692         if (retry == READ_ERR) {
1693                 rbio = bch2_rbio_free(rbio);
1694
1695                 rbio->bio.bi_status = error;
1696                 bch2_rbio_done(rbio);
1697         } else {
1698                 bch2_rbio_punt(rbio, bch2_rbio_retry,
1699                                RBIO_CONTEXT_UNBOUND, system_unbound_wq);
1700         }
1701 }
1702
1703 static int __bch2_rbio_narrow_crcs(struct btree_trans *trans,
1704                                    struct bch_read_bio *rbio)
1705 {
1706         struct bch_fs *c = rbio->c;
1707         u64 data_offset = rbio->pos.offset - rbio->pick.crc.offset;
1708         struct bch_extent_crc_unpacked new_crc;
1709         struct btree_iter *iter = NULL;
1710         struct bkey_i *new;
1711         struct bkey_s_c k;
1712         int ret = 0;
1713
1714         if (crc_is_compressed(rbio->pick.crc))
1715                 return 0;
1716
1717         iter = bch2_trans_get_iter(trans, BTREE_ID_EXTENTS, rbio->pos,
1718                                    BTREE_ITER_SLOTS|BTREE_ITER_INTENT);
1719         if ((ret = PTR_ERR_OR_ZERO(iter)))
1720                 goto out;
1721
1722         k = bch2_btree_iter_peek_slot(iter);
1723         if ((ret = bkey_err(k)))
1724                 goto out;
1725
1726         /*
1727          * going to be temporarily appending another checksum entry:
1728          */
1729         new = bch2_trans_kmalloc(trans, bkey_bytes(k.k) +
1730                                  BKEY_EXTENT_U64s_MAX * 8);
1731         if ((ret = PTR_ERR_OR_ZERO(new)))
1732                 goto out;
1733
1734         bkey_reassemble(new, k);
1735         k = bkey_i_to_s_c(new);
1736
1737         if (bversion_cmp(k.k->version, rbio->version) ||
1738             !bch2_bkey_matches_ptr(c, k, rbio->pick.ptr, data_offset))
1739                 goto out;
1740
1741         /* Extent was merged? */
1742         if (bkey_start_offset(k.k) < data_offset ||
1743             k.k->p.offset > data_offset + rbio->pick.crc.uncompressed_size)
1744                 goto out;
1745
1746         if (bch2_rechecksum_bio(c, &rbio->bio, rbio->version,
1747                         rbio->pick.crc, NULL, &new_crc,
1748                         bkey_start_offset(k.k) - data_offset, k.k->size,
1749                         rbio->pick.crc.csum_type)) {
1750                 bch_err(c, "error verifying existing checksum while narrowing checksum (memory corruption?)");
1751                 ret = 0;
1752                 goto out;
1753         }
1754
1755         if (!bch2_bkey_narrow_crcs(new, new_crc))
1756                 goto out;
1757
1758         bch2_trans_update(trans, iter, new, 0);
1759 out:
1760         bch2_trans_iter_put(trans, iter);
1761         return ret;
1762 }
1763
1764 static noinline void bch2_rbio_narrow_crcs(struct bch_read_bio *rbio)
1765 {
1766         bch2_trans_do(rbio->c, NULL, NULL, BTREE_INSERT_NOFAIL,
1767                       __bch2_rbio_narrow_crcs(&trans, rbio));
1768 }
1769
1770 /* Inner part that may run in process context */
1771 static void __bch2_read_endio(struct work_struct *work)
1772 {
1773         struct bch_read_bio *rbio =
1774                 container_of(work, struct bch_read_bio, work);
1775         struct bch_fs *c        = rbio->c;
1776         struct bch_dev *ca      = bch_dev_bkey_exists(c, rbio->pick.ptr.dev);
1777         struct bio *src         = &rbio->bio;
1778         struct bio *dst         = &bch2_rbio_parent(rbio)->bio;
1779         struct bvec_iter dst_iter = rbio->bvec_iter;
1780         struct bch_extent_crc_unpacked crc = rbio->pick.crc;
1781         struct nonce nonce = extent_nonce(rbio->version, crc);
1782         struct bch_csum csum;
1783
1784         /* Reset iterator for checksumming and copying bounced data: */
1785         if (rbio->bounce) {
1786                 src->bi_iter.bi_size            = crc.compressed_size << 9;
1787                 src->bi_iter.bi_idx             = 0;
1788                 src->bi_iter.bi_bvec_done       = 0;
1789         } else {
1790                 src->bi_iter                    = rbio->bvec_iter;
1791         }
1792
1793         csum = bch2_checksum_bio(c, crc.csum_type, nonce, src);
1794         if (bch2_crc_cmp(csum, rbio->pick.crc.csum))
1795                 goto csum_err;
1796
1797         if (unlikely(rbio->narrow_crcs))
1798                 bch2_rbio_narrow_crcs(rbio);
1799
1800         if (rbio->flags & BCH_READ_NODECODE)
1801                 goto nodecode;
1802
1803         /* Adjust crc to point to subset of data we want: */
1804         crc.offset     += rbio->offset_into_extent;
1805         crc.live_size   = bvec_iter_sectors(rbio->bvec_iter);
1806
1807         if (crc_is_compressed(crc)) {
1808                 bch2_encrypt_bio(c, crc.csum_type, nonce, src);
1809                 if (bch2_bio_uncompress(c, src, dst, dst_iter, crc))
1810                         goto decompression_err;
1811         } else {
1812                 /* don't need to decrypt the entire bio: */
1813                 nonce = nonce_add(nonce, crc.offset << 9);
1814                 bio_advance(src, crc.offset << 9);
1815
1816                 BUG_ON(src->bi_iter.bi_size < dst_iter.bi_size);
1817                 src->bi_iter.bi_size = dst_iter.bi_size;
1818
1819                 bch2_encrypt_bio(c, crc.csum_type, nonce, src);
1820
1821                 if (rbio->bounce) {
1822                         struct bvec_iter src_iter = src->bi_iter;
1823                         bio_copy_data_iter(dst, &dst_iter, src, &src_iter);
1824                 }
1825         }
1826
1827         if (rbio->promote) {
1828                 /*
1829                  * Re encrypt data we decrypted, so it's consistent with
1830                  * rbio->crc:
1831                  */
1832                 bch2_encrypt_bio(c, crc.csum_type, nonce, src);
1833                 promote_start(rbio->promote, rbio);
1834                 rbio->promote = NULL;
1835         }
1836 nodecode:
1837         if (likely(!(rbio->flags & BCH_READ_IN_RETRY))) {
1838                 rbio = bch2_rbio_free(rbio);
1839                 bch2_rbio_done(rbio);
1840         }
1841         return;
1842 csum_err:
1843         /*
1844          * Checksum error: if the bio wasn't bounced, we may have been
1845          * reading into buffers owned by userspace (that userspace can
1846          * scribble over) - retry the read, bouncing it this time:
1847          */
1848         if (!rbio->bounce && (rbio->flags & BCH_READ_USER_MAPPED)) {
1849                 rbio->flags |= BCH_READ_MUST_BOUNCE;
1850                 bch2_rbio_error(rbio, READ_RETRY, BLK_STS_IOERR);
1851                 return;
1852         }
1853
1854         bch2_dev_io_error(ca,
1855                 "data checksum error, inode %llu offset %llu: expected %0llx:%0llx got %0llx:%0llx (type %u)",
1856                 rbio->pos.inode, (u64) rbio->bvec_iter.bi_sector,
1857                 rbio->pick.crc.csum.hi, rbio->pick.crc.csum.lo,
1858                 csum.hi, csum.lo, crc.csum_type);
1859         bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR);
1860         return;
1861 decompression_err:
1862         __bcache_io_error(c, "decompression error, inode %llu offset %llu",
1863                           rbio->pos.inode,
1864                           (u64) rbio->bvec_iter.bi_sector);
1865         bch2_rbio_error(rbio, READ_ERR, BLK_STS_IOERR);
1866         return;
1867 }
1868
1869 static void bch2_read_endio(struct bio *bio)
1870 {
1871         struct bch_read_bio *rbio =
1872                 container_of(bio, struct bch_read_bio, bio);
1873         struct bch_fs *c        = rbio->c;
1874         struct bch_dev *ca      = bch_dev_bkey_exists(c, rbio->pick.ptr.dev);
1875         struct workqueue_struct *wq = NULL;
1876         enum rbio_context context = RBIO_CONTEXT_NULL;
1877
1878         if (rbio->have_ioref) {
1879                 bch2_latency_acct(ca, rbio->submit_time, READ);
1880                 percpu_ref_put(&ca->io_ref);
1881         }
1882
1883         if (!rbio->split)
1884                 rbio->bio.bi_end_io = rbio->end_io;
1885
1886         if (bch2_dev_io_err_on(bio->bi_status, ca, "data read")) {
1887                 bch2_rbio_error(rbio, READ_RETRY_AVOID, bio->bi_status);
1888                 return;
1889         }
1890
1891         if (rbio->pick.ptr.cached &&
1892             (((rbio->flags & BCH_READ_RETRY_IF_STALE) && race_fault()) ||
1893              ptr_stale(ca, &rbio->pick.ptr))) {
1894                 atomic_long_inc(&c->read_realloc_races);
1895
1896                 if (rbio->flags & BCH_READ_RETRY_IF_STALE)
1897                         bch2_rbio_error(rbio, READ_RETRY, BLK_STS_AGAIN);
1898                 else
1899                         bch2_rbio_error(rbio, READ_ERR, BLK_STS_AGAIN);
1900                 return;
1901         }
1902
1903         if (rbio->narrow_crcs ||
1904             crc_is_compressed(rbio->pick.crc) ||
1905             bch2_csum_type_is_encryption(rbio->pick.crc.csum_type))
1906                 context = RBIO_CONTEXT_UNBOUND, wq = system_unbound_wq;
1907         else if (rbio->pick.crc.csum_type)
1908                 context = RBIO_CONTEXT_HIGHPRI, wq = system_highpri_wq;
1909
1910         bch2_rbio_punt(rbio, __bch2_read_endio, context, wq);
1911 }
1912
1913 int __bch2_read_indirect_extent(struct btree_trans *trans,
1914                                 unsigned *offset_into_extent,
1915                                 struct bkey_i *orig_k)
1916 {
1917         struct btree_iter *iter;
1918         struct bkey_s_c k;
1919         u64 reflink_offset;
1920         int ret;
1921
1922         reflink_offset = le64_to_cpu(bkey_i_to_reflink_p(orig_k)->v.idx) +
1923                 *offset_into_extent;
1924
1925         iter = bch2_trans_get_iter(trans, BTREE_ID_REFLINK,
1926                                    POS(0, reflink_offset),
1927                                    BTREE_ITER_SLOTS);
1928         ret = PTR_ERR_OR_ZERO(iter);
1929         if (ret)
1930                 return ret;
1931
1932         k = bch2_btree_iter_peek_slot(iter);
1933         ret = bkey_err(k);
1934         if (ret)
1935                 goto err;
1936
1937         if (k.k->type != KEY_TYPE_reflink_v) {
1938                 __bcache_io_error(trans->c,
1939                                 "pointer to nonexistent indirect extent");
1940                 ret = -EIO;
1941                 goto err;
1942         }
1943
1944         *offset_into_extent = iter->pos.offset - bkey_start_offset(k.k);
1945         bkey_reassemble(orig_k, k);
1946 err:
1947         bch2_trans_iter_put(trans, iter);
1948         return ret;
1949 }
1950
1951 int __bch2_read_extent(struct bch_fs *c, struct bch_read_bio *orig,
1952                        struct bvec_iter iter, struct bkey_s_c k,
1953                        unsigned offset_into_extent,
1954                        struct bch_io_failures *failed, unsigned flags)
1955 {
1956         struct extent_ptr_decoded pick;
1957         struct bch_read_bio *rbio = NULL;
1958         struct bch_dev *ca;
1959         struct promote_op *promote = NULL;
1960         bool bounce = false, read_full = false, narrow_crcs = false;
1961         struct bpos pos = bkey_start_pos(k.k);
1962         int pick_ret;
1963
1964         if (k.k->type == KEY_TYPE_inline_data) {
1965                 struct bkey_s_c_inline_data d = bkey_s_c_to_inline_data(k);
1966                 unsigned bytes = min_t(unsigned, iter.bi_size,
1967                                        bkey_val_bytes(d.k));
1968
1969                 swap(iter.bi_size, bytes);
1970                 memcpy_to_bio(&orig->bio, iter, d.v->data);
1971                 swap(iter.bi_size, bytes);
1972                 bio_advance_iter(&orig->bio, &iter, bytes);
1973                 zero_fill_bio_iter(&orig->bio, iter);
1974                 goto out_read_done;
1975         }
1976
1977         pick_ret = bch2_bkey_pick_read_device(c, k, failed, &pick);
1978
1979         /* hole or reservation - just zero fill: */
1980         if (!pick_ret)
1981                 goto hole;
1982
1983         if (pick_ret < 0) {
1984                 __bcache_io_error(c, "no device to read from");
1985                 goto err;
1986         }
1987
1988         if (pick_ret > 0)
1989                 ca = bch_dev_bkey_exists(c, pick.ptr.dev);
1990
1991         if (flags & BCH_READ_NODECODE) {
1992                 /*
1993                  * can happen if we retry, and the extent we were going to read
1994                  * has been merged in the meantime:
1995                  */
1996                 if (pick.crc.compressed_size > orig->bio.bi_vcnt * PAGE_SECTORS)
1997                         goto hole;
1998
1999                 iter.bi_size    = pick.crc.compressed_size << 9;
2000                 goto get_bio;
2001         }
2002
2003         if (!(flags & BCH_READ_LAST_FRAGMENT) ||
2004             bio_flagged(&orig->bio, BIO_CHAIN))
2005                 flags |= BCH_READ_MUST_CLONE;
2006
2007         narrow_crcs = !(flags & BCH_READ_IN_RETRY) &&
2008                 bch2_can_narrow_extent_crcs(k, pick.crc);
2009
2010         if (narrow_crcs && (flags & BCH_READ_USER_MAPPED))
2011                 flags |= BCH_READ_MUST_BOUNCE;
2012
2013         EBUG_ON(offset_into_extent + bvec_iter_sectors(iter) > k.k->size);
2014
2015         if (crc_is_compressed(pick.crc) ||
2016             (pick.crc.csum_type != BCH_CSUM_NONE &&
2017              (bvec_iter_sectors(iter) != pick.crc.uncompressed_size ||
2018               (bch2_csum_type_is_encryption(pick.crc.csum_type) &&
2019                (flags & BCH_READ_USER_MAPPED)) ||
2020               (flags & BCH_READ_MUST_BOUNCE)))) {
2021                 read_full = true;
2022                 bounce = true;
2023         }
2024
2025         if (orig->opts.promote_target)
2026                 promote = promote_alloc(c, iter, k, &pick, orig->opts, flags,
2027                                         &rbio, &bounce, &read_full);
2028
2029         if (!read_full) {
2030                 EBUG_ON(crc_is_compressed(pick.crc));
2031                 EBUG_ON(pick.crc.csum_type &&
2032                         (bvec_iter_sectors(iter) != pick.crc.uncompressed_size ||
2033                          bvec_iter_sectors(iter) != pick.crc.live_size ||
2034                          pick.crc.offset ||
2035                          offset_into_extent));
2036
2037                 pos.offset += offset_into_extent;
2038                 pick.ptr.offset += pick.crc.offset +
2039                         offset_into_extent;
2040                 offset_into_extent              = 0;
2041                 pick.crc.compressed_size        = bvec_iter_sectors(iter);
2042                 pick.crc.uncompressed_size      = bvec_iter_sectors(iter);
2043                 pick.crc.offset                 = 0;
2044                 pick.crc.live_size              = bvec_iter_sectors(iter);
2045                 offset_into_extent              = 0;
2046         }
2047 get_bio:
2048         if (rbio) {
2049                 /*
2050                  * promote already allocated bounce rbio:
2051                  * promote needs to allocate a bio big enough for uncompressing
2052                  * data in the write path, but we're not going to use it all
2053                  * here:
2054                  */
2055                 EBUG_ON(rbio->bio.bi_iter.bi_size <
2056                        pick.crc.compressed_size << 9);
2057                 rbio->bio.bi_iter.bi_size =
2058                         pick.crc.compressed_size << 9;
2059         } else if (bounce) {
2060                 unsigned sectors = pick.crc.compressed_size;
2061
2062                 rbio = rbio_init(bio_alloc_bioset(GFP_NOIO,
2063                                                   DIV_ROUND_UP(sectors, PAGE_SECTORS),
2064                                                   &c->bio_read_split),
2065                                  orig->opts);
2066
2067                 bch2_bio_alloc_pages_pool(c, &rbio->bio, sectors << 9);
2068                 rbio->bounce    = true;
2069                 rbio->split     = true;
2070         } else if (flags & BCH_READ_MUST_CLONE) {
2071                 /*
2072                  * Have to clone if there were any splits, due to error
2073                  * reporting issues (if a split errored, and retrying didn't
2074                  * work, when it reports the error to its parent (us) we don't
2075                  * know if the error was from our bio, and we should retry, or
2076                  * from the whole bio, in which case we don't want to retry and
2077                  * lose the error)
2078                  */
2079                 rbio = rbio_init(bio_clone_fast(&orig->bio, GFP_NOIO,
2080                                                 &c->bio_read_split),
2081                                  orig->opts);
2082                 rbio->bio.bi_iter = iter;
2083                 rbio->split     = true;
2084         } else {
2085                 rbio = orig;
2086                 rbio->bio.bi_iter = iter;
2087                 EBUG_ON(bio_flagged(&rbio->bio, BIO_CHAIN));
2088         }
2089
2090         EBUG_ON(bio_sectors(&rbio->bio) != pick.crc.compressed_size);
2091
2092         rbio->c                 = c;
2093         rbio->submit_time       = local_clock();
2094         if (rbio->split)
2095                 rbio->parent    = orig;
2096         else
2097                 rbio->end_io    = orig->bio.bi_end_io;
2098         rbio->bvec_iter         = iter;
2099         rbio->offset_into_extent= offset_into_extent;
2100         rbio->flags             = flags;
2101         rbio->have_ioref        = pick_ret > 0 && bch2_dev_get_ioref(ca, READ);
2102         rbio->narrow_crcs       = narrow_crcs;
2103         rbio->hole              = 0;
2104         rbio->retry             = 0;
2105         rbio->context           = 0;
2106         /* XXX: only initialize this if needed */
2107         rbio->devs_have         = bch2_bkey_devs(k);
2108         rbio->pick              = pick;
2109         rbio->pos               = pos;
2110         rbio->version           = k.k->version;
2111         rbio->promote           = promote;
2112         INIT_WORK(&rbio->work, NULL);
2113
2114         rbio->bio.bi_opf        = orig->bio.bi_opf;
2115         rbio->bio.bi_iter.bi_sector = pick.ptr.offset;
2116         rbio->bio.bi_end_io     = bch2_read_endio;
2117
2118         if (rbio->bounce)
2119                 trace_read_bounce(&rbio->bio);
2120
2121         bch2_increment_clock(c, bio_sectors(&rbio->bio), READ);
2122
2123         rcu_read_lock();
2124         bucket_io_clock_reset(c, ca, PTR_BUCKET_NR(ca, &pick.ptr), READ);
2125         rcu_read_unlock();
2126
2127         if (!(flags & (BCH_READ_IN_RETRY|BCH_READ_LAST_FRAGMENT))) {
2128                 bio_inc_remaining(&orig->bio);
2129                 trace_read_split(&orig->bio);
2130         }
2131
2132         if (!rbio->pick.idx) {
2133                 if (!rbio->have_ioref) {
2134                         __bcache_io_error(c, "no device to read from");
2135                         bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR);
2136                         goto out;
2137                 }
2138
2139                 this_cpu_add(ca->io_done->sectors[READ][BCH_DATA_USER],
2140                              bio_sectors(&rbio->bio));
2141                 bio_set_dev(&rbio->bio, ca->disk_sb.bdev);
2142
2143                 if (likely(!(flags & BCH_READ_IN_RETRY)))
2144                         submit_bio(&rbio->bio);
2145                 else
2146                         submit_bio_wait(&rbio->bio);
2147         } else {
2148                 /* Attempting reconstruct read: */
2149                 if (bch2_ec_read_extent(c, rbio)) {
2150                         bch2_rbio_error(rbio, READ_RETRY_AVOID, BLK_STS_IOERR);
2151                         goto out;
2152                 }
2153
2154                 if (likely(!(flags & BCH_READ_IN_RETRY)))
2155                         bio_endio(&rbio->bio);
2156         }
2157 out:
2158         if (likely(!(flags & BCH_READ_IN_RETRY))) {
2159                 return 0;
2160         } else {
2161                 int ret;
2162
2163                 rbio->context = RBIO_CONTEXT_UNBOUND;
2164                 bch2_read_endio(&rbio->bio);
2165
2166                 ret = rbio->retry;
2167                 rbio = bch2_rbio_free(rbio);
2168
2169                 if (ret == READ_RETRY_AVOID) {
2170                         bch2_mark_io_failure(failed, &pick);
2171                         ret = READ_RETRY;
2172                 }
2173
2174                 return ret;
2175         }
2176
2177 err:
2178         if (flags & BCH_READ_IN_RETRY)
2179                 return READ_ERR;
2180
2181         orig->bio.bi_status = BLK_STS_IOERR;
2182         goto out_read_done;
2183
2184 hole:
2185         /*
2186          * won't normally happen in the BCH_READ_NODECODE
2187          * (bch2_move_extent()) path, but if we retry and the extent we wanted
2188          * to read no longer exists we have to signal that:
2189          */
2190         if (flags & BCH_READ_NODECODE)
2191                 orig->hole = true;
2192
2193         zero_fill_bio_iter(&orig->bio, iter);
2194 out_read_done:
2195         if (flags & BCH_READ_LAST_FRAGMENT)
2196                 bch2_rbio_done(orig);
2197         return 0;
2198 }
2199
2200 void bch2_read(struct bch_fs *c, struct bch_read_bio *rbio, u64 inode)
2201 {
2202         struct btree_trans trans;
2203         struct btree_iter *iter;
2204         struct bkey_on_stack sk;
2205         struct bkey_s_c k;
2206         unsigned flags = BCH_READ_RETRY_IF_STALE|
2207                 BCH_READ_MAY_PROMOTE|
2208                 BCH_READ_USER_MAPPED;
2209         int ret;
2210
2211         BUG_ON(rbio->_state);
2212         BUG_ON(flags & BCH_READ_NODECODE);
2213         BUG_ON(flags & BCH_READ_IN_RETRY);
2214
2215         rbio->c = c;
2216         rbio->start_time = local_clock();
2217
2218         bkey_on_stack_init(&sk);
2219         bch2_trans_init(&trans, c, 0, 0);
2220 retry:
2221         bch2_trans_begin(&trans);
2222
2223         iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS,
2224                                    POS(inode, rbio->bio.bi_iter.bi_sector),
2225                                    BTREE_ITER_SLOTS);
2226         while (1) {
2227                 unsigned bytes, sectors, offset_into_extent;
2228
2229                 bch2_btree_iter_set_pos(iter,
2230                                 POS(inode, rbio->bio.bi_iter.bi_sector));
2231
2232                 k = bch2_btree_iter_peek_slot(iter);
2233                 ret = bkey_err(k);
2234                 if (ret)
2235                         goto err;
2236
2237                 offset_into_extent = iter->pos.offset -
2238                         bkey_start_offset(k.k);
2239                 sectors = k.k->size - offset_into_extent;
2240
2241                 bkey_on_stack_reassemble(&sk, c, k);
2242                 k = bkey_i_to_s_c(sk.k);
2243
2244                 ret = bch2_read_indirect_extent(&trans,
2245                                         &offset_into_extent, sk.k);
2246                 if (ret)
2247                         goto err;
2248
2249                 /*
2250                  * With indirect extents, the amount of data to read is the min
2251                  * of the original extent and the indirect extent:
2252                  */
2253                 sectors = min(sectors, k.k->size - offset_into_extent);
2254
2255                 /*
2256                  * Unlock the iterator while the btree node's lock is still in
2257                  * cache, before doing the IO:
2258                  */
2259                 bch2_trans_unlock(&trans);
2260
2261                 bytes = min(sectors, bio_sectors(&rbio->bio)) << 9;
2262                 swap(rbio->bio.bi_iter.bi_size, bytes);
2263
2264                 if (rbio->bio.bi_iter.bi_size == bytes)
2265                         flags |= BCH_READ_LAST_FRAGMENT;
2266
2267                 bch2_read_extent(c, rbio, k, offset_into_extent, flags);
2268
2269                 if (flags & BCH_READ_LAST_FRAGMENT)
2270                         break;
2271
2272                 swap(rbio->bio.bi_iter.bi_size, bytes);
2273                 bio_advance(&rbio->bio, bytes);
2274         }
2275 out:
2276         bch2_trans_exit(&trans);
2277         bkey_on_stack_exit(&sk, c);
2278         return;
2279 err:
2280         if (ret == -EINTR)
2281                 goto retry;
2282
2283         bcache_io_error(c, &rbio->bio, "btree IO error: %i", ret);
2284         bch2_rbio_done(rbio);
2285         goto out;
2286 }
2287
2288 void bch2_fs_io_exit(struct bch_fs *c)
2289 {
2290         if (c->promote_table.tbl)
2291                 rhashtable_destroy(&c->promote_table);
2292         mempool_exit(&c->bio_bounce_pages);
2293         bioset_exit(&c->bio_write);
2294         bioset_exit(&c->bio_read_split);
2295         bioset_exit(&c->bio_read);
2296 }
2297
2298 int bch2_fs_io_init(struct bch_fs *c)
2299 {
2300         if (bioset_init(&c->bio_read, 1, offsetof(struct bch_read_bio, bio),
2301                         BIOSET_NEED_BVECS) ||
2302             bioset_init(&c->bio_read_split, 1, offsetof(struct bch_read_bio, bio),
2303                         BIOSET_NEED_BVECS) ||
2304             bioset_init(&c->bio_write, 1, offsetof(struct bch_write_bio, bio),
2305                         BIOSET_NEED_BVECS) ||
2306             mempool_init_page_pool(&c->bio_bounce_pages,
2307                                    max_t(unsigned,
2308                                          c->opts.btree_node_size,
2309                                          c->sb.encoded_extent_max) /
2310                                    PAGE_SECTORS, 0) ||
2311             rhashtable_init(&c->promote_table, &bch_promote_params))
2312                 return -ENOMEM;
2313
2314         return 0;
2315 }