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

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright 2012 Google, Inc.
   4  *
   5  * Foreground allocator code: allocate buckets from freelist, and allocate in
   6  * sector granularity from writepoints.
   7  *
   8  * bch2_bucket_alloc() allocates a single bucket from a specific device.
   9  *
  10  * bch2_bucket_alloc_set() allocates one or more buckets from different devices
  11  * in a given filesystem.
  12  */
  13
  14 #include "bcachefs.h"
  15 #include "alloc_background.h"
  16 #include "alloc_foreground.h"
  17 #include "backpointers.h"
  18 #include "btree_iter.h"
  19 #include "btree_update.h"
  20 #include "btree_gc.h"
  21 #include "buckets.h"
  22 #include "buckets_waiting_for_journal.h"
  23 #include "clock.h"
  24 #include "debug.h"
  25 #include "disk_groups.h"
  26 #include "ec.h"
  27 #include "error.h"
  28 #include "io.h"
  29 #include "journal.h"
  30 #include "movinggc.h"
  31
  32 #include <linux/math64.h>
  33 #include <linux/rculist.h>
  34 #include <linux/rcupdate.h>
  35 #include <trace/events/bcachefs.h>
  36
  37 const char * const bch2_alloc_reserves[] = {
  38 #define x(t) #t,
  39         BCH_ALLOC_RESERVES()
  40 #undef x
  41         NULL
  42 };
  43
  44 /*
  45  * Open buckets represent a bucket that's currently being allocated from.  They
  46  * serve two purposes:
  47  *
  48  *  - They track buckets that have been partially allocated, allowing for
  49  *    sub-bucket sized allocations - they're used by the sector allocator below
  50  *
  51  *  - They provide a reference to the buckets they own that mark and sweep GC
  52  *    can find, until the new allocation has a pointer to it inserted into the
  53  *    btree
  54  *
  55  * When allocating some space with the sector allocator, the allocation comes
  56  * with a reference to an open bucket - the caller is required to put that
  57  * reference _after_ doing the index update that makes its allocation reachable.
  58  */
  59
  60 static void bch2_open_bucket_hash_add(struct bch_fs *c, struct open_bucket *ob)
  61 {
  62         open_bucket_idx_t idx = ob - c->open_buckets;
  63         open_bucket_idx_t *slot = open_bucket_hashslot(c, ob->dev, ob->bucket);
  64
  65         ob->hash = *slot;
  66         *slot = idx;
  67 }
  68
  69 static void bch2_open_bucket_hash_remove(struct bch_fs *c, struct open_bucket *ob)
  70 {
  71         open_bucket_idx_t idx = ob - c->open_buckets;
  72         open_bucket_idx_t *slot = open_bucket_hashslot(c, ob->dev, ob->bucket);
  73
  74         while (*slot != idx) {
  75                 BUG_ON(!*slot);
  76                 slot = &c->open_buckets[*slot].hash;
  77         }
  78
  79         *slot = ob->hash;
  80         ob->hash = 0;
  81 }
  82
  83 void __bch2_open_bucket_put(struct bch_fs *c, struct open_bucket *ob)
  84 {
  85         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
  86
  87         if (ob->ec) {
  88                 bch2_ec_bucket_written(c, ob);
  89                 return;
  90         }
  91
  92         percpu_down_read(&c->mark_lock);
  93         spin_lock(&ob->lock);
  94
  95         ob->valid = false;
  96         ob->data_type = 0;
  97
  98         spin_unlock(&ob->lock);
  99         percpu_up_read(&c->mark_lock);
 100
 101         spin_lock(&c->freelist_lock);
 102         bch2_open_bucket_hash_remove(c, ob);
 103
 104         ob->freelist = c->open_buckets_freelist;
 105         c->open_buckets_freelist = ob - c->open_buckets;
 106
 107         c->open_buckets_nr_free++;
 108         ca->nr_open_buckets--;
 109         spin_unlock(&c->freelist_lock);
 110
 111         closure_wake_up(&c->open_buckets_wait);
 112 }
 113
 114 void bch2_open_bucket_write_error(struct bch_fs *c,
 115                                   struct open_buckets *obs,
 116                                   unsigned dev)
 117 {
 118         struct open_bucket *ob;
 119         unsigned i;
 120
 121         open_bucket_for_each(c, obs, ob, i)
 122                 if (ob->dev == dev && ob->ec)
 123                         bch2_ec_bucket_cancel(c, ob);
 124 }
 125
 126 static struct open_bucket *bch2_open_bucket_alloc(struct bch_fs *c)
 127 {
 128         struct open_bucket *ob;
 129
 130         BUG_ON(!c->open_buckets_freelist || !c->open_buckets_nr_free);
 131
 132         ob = c->open_buckets + c->open_buckets_freelist;
 133         c->open_buckets_freelist = ob->freelist;
 134         atomic_set(&ob->pin, 1);
 135         ob->data_type = 0;
 136
 137         c->open_buckets_nr_free--;
 138         return ob;
 139 }
 140
 141 static void open_bucket_free_unused(struct bch_fs *c,
 142                                     struct write_point *wp,
 143                                     struct open_bucket *ob)
 144 {
 145         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
 146         bool may_realloc = wp->data_type == BCH_DATA_user;
 147
 148         BUG_ON(ca->open_buckets_partial_nr >
 149                ARRAY_SIZE(ca->open_buckets_partial));
 150
 151         if (ca->open_buckets_partial_nr <
 152             ARRAY_SIZE(ca->open_buckets_partial) &&
 153             may_realloc) {
 154                 spin_lock(&c->freelist_lock);
 155                 ob->on_partial_list = true;
 156                 ca->open_buckets_partial[ca->open_buckets_partial_nr++] =
 157                         ob - c->open_buckets;
 158                 spin_unlock(&c->freelist_lock);
 159
 160                 closure_wake_up(&c->open_buckets_wait);
 161                 closure_wake_up(&c->freelist_wait);
 162         } else {
 163                 bch2_open_bucket_put(c, ob);
 164         }
 165 }
 166
 167 /* _only_ for allocating the journal on a new device: */
 168 long bch2_bucket_alloc_new_fs(struct bch_dev *ca)
 169 {
 170         while (ca->new_fs_bucket_idx < ca->mi.nbuckets) {
 171                 u64 b = ca->new_fs_bucket_idx++;
 172
 173                 if (!is_superblock_bucket(ca, b) &&
 174                     (!ca->buckets_nouse || !test_bit(b, ca->buckets_nouse)))
 175                         return b;
 176         }
 177
 178         return -1;
 179 }
 180
 181 static inline unsigned open_buckets_reserved(enum alloc_reserve reserve)
 182 {
 183         switch (reserve) {
 184         case RESERVE_btree:
 185         case RESERVE_btree_movinggc:
 186                 return 0;
 187         case RESERVE_movinggc:
 188                 return OPEN_BUCKETS_COUNT / 4;
 189         default:
 190                 return OPEN_BUCKETS_COUNT / 2;
 191         }
 192 }
 193
 194 static struct open_bucket *__try_alloc_bucket(struct bch_fs *c, struct bch_dev *ca,
 195                                               u64 bucket,
 196                                               enum alloc_reserve reserve,
 197                                               const struct bch_alloc_v4 *a,
 198                                               struct bucket_alloc_state *s,
 199                                               struct closure *cl)
 200 {
 201         struct open_bucket *ob;
 202
 203         if (unlikely(ca->buckets_nouse && test_bit(bucket, ca->buckets_nouse))) {
 204                 s->skipped_nouse++;
 205                 return NULL;
 206         }
 207
 208         if (bch2_bucket_is_open(c, ca->dev_idx, bucket)) {
 209                 s->skipped_open++;
 210                 return NULL;
 211         }
 212
 213         if (bch2_bucket_needs_journal_commit(&c->buckets_waiting_for_journal,
 214                         c->journal.flushed_seq_ondisk, ca->dev_idx, bucket)) {
 215                 s->skipped_need_journal_commit++;
 216                 return NULL;
 217         }
 218
 219         if (bch2_bucket_nocow_is_locked(&c->nocow_locks, POS(ca->dev_idx, bucket))) {
 220                 s->skipped_nocow++;
 221                 return NULL;
 222         }
 223
 224         spin_lock(&c->freelist_lock);
 225
 226         if (unlikely(c->open_buckets_nr_free <= open_buckets_reserved(reserve))) {
 227                 if (cl)
 228                         closure_wait(&c->open_buckets_wait, cl);
 229
 230                 if (!c->blocked_allocate_open_bucket)
 231                         c->blocked_allocate_open_bucket = local_clock();
 232
 233                 spin_unlock(&c->freelist_lock);
 234                 return ERR_PTR(-BCH_ERR_open_buckets_empty);
 235         }
 236
 237         /* Recheck under lock: */
 238         if (bch2_bucket_is_open(c, ca->dev_idx, bucket)) {
 239                 spin_unlock(&c->freelist_lock);
 240                 s->skipped_open++;
 241                 return NULL;
 242         }
 243
 244         ob = bch2_open_bucket_alloc(c);
 245
 246         spin_lock(&ob->lock);
 247
 248         ob->valid       = true;
 249         ob->sectors_free = ca->mi.bucket_size;
 250         ob->alloc_reserve = reserve;
 251         ob->dev         = ca->dev_idx;
 252         ob->gen         = a->gen;
 253         ob->bucket      = bucket;
 254         spin_unlock(&ob->lock);
 255
 256         ca->nr_open_buckets++;
 257         bch2_open_bucket_hash_add(c, ob);
 258
 259         if (c->blocked_allocate_open_bucket) {
 260                 bch2_time_stats_update(
 261                         &c->times[BCH_TIME_blocked_allocate_open_bucket],
 262                         c->blocked_allocate_open_bucket);
 263                 c->blocked_allocate_open_bucket = 0;
 264         }
 265
 266         if (c->blocked_allocate) {
 267                 bch2_time_stats_update(
 268                         &c->times[BCH_TIME_blocked_allocate],
 269                         c->blocked_allocate);
 270                 c->blocked_allocate = 0;
 271         }
 272
 273         spin_unlock(&c->freelist_lock);
 274
 275         return ob;
 276 }
 277
 278 static struct open_bucket *try_alloc_bucket(struct btree_trans *trans, struct bch_dev *ca,
 279                                             enum alloc_reserve reserve, u64 free_entry,
 280                                             struct bucket_alloc_state *s,
 281                                             struct bkey_s_c freespace_k,
 282                                             struct closure *cl)
 283 {
 284         struct bch_fs *c = trans->c;
 285         struct btree_iter iter = { NULL };
 286         struct bkey_s_c k;
 287         struct open_bucket *ob;
 288         struct bch_alloc_v4 a_convert;
 289         const struct bch_alloc_v4 *a;
 290         u64 b = free_entry & ~(~0ULL << 56);
 291         unsigned genbits = free_entry >> 56;
 292         struct printbuf buf = PRINTBUF;
 293         int ret;
 294
 295         if (b < ca->mi.first_bucket || b >= ca->mi.nbuckets) {
 296                 prt_printf(&buf, "freespace btree has bucket outside allowed range %u-%llu\n"
 297                        "  freespace key ",
 298                         ca->mi.first_bucket, ca->mi.nbuckets);
 299                 bch2_bkey_val_to_text(&buf, c, freespace_k);
 300                 bch2_trans_inconsistent(trans, "%s", buf.buf);
 301                 ob = ERR_PTR(-EIO);
 302                 goto err;
 303         }
 304
 305         bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc, POS(ca->dev_idx, b), BTREE_ITER_CACHED);
 306         k = bch2_btree_iter_peek_slot(&iter);
 307         ret = bkey_err(k);
 308         if (ret) {
 309                 ob = ERR_PTR(ret);
 310                 goto err;
 311         }
 312
 313         a = bch2_alloc_to_v4(k, &a_convert);
 314
 315         if (a->data_type != BCH_DATA_free) {
 316                 if (!test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
 317                         ob = NULL;
 318                         goto err;
 319                 }
 320
 321                 prt_printf(&buf, "non free bucket in freespace btree\n"
 322                        "  freespace key ");
 323                 bch2_bkey_val_to_text(&buf, c, freespace_k);
 324                 prt_printf(&buf, "\n  ");
 325                 bch2_bkey_val_to_text(&buf, c, k);
 326                 bch2_trans_inconsistent(trans, "%s", buf.buf);
 327                 ob = ERR_PTR(-EIO);
 328                 goto err;
 329         }
 330
 331         if (genbits != (alloc_freespace_genbits(*a) >> 56) &&
 332             test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
 333                 prt_printf(&buf, "bucket in freespace btree with wrong genbits (got %u should be %llu)\n"
 334                        "  freespace key ",
 335                        genbits, alloc_freespace_genbits(*a) >> 56);
 336                 bch2_bkey_val_to_text(&buf, c, freespace_k);
 337                 prt_printf(&buf, "\n  ");
 338                 bch2_bkey_val_to_text(&buf, c, k);
 339                 bch2_trans_inconsistent(trans, "%s", buf.buf);
 340                 ob = ERR_PTR(-EIO);
 341                 goto err;
 342
 343         }
 344
 345         if (!test_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags)) {
 346                 struct bch_backpointer bp;
 347                 u64 bp_offset = 0;
 348
 349                 ret = bch2_get_next_backpointer(trans, POS(ca->dev_idx, b), -1,
 350                                                 &bp_offset, &bp,
 351                                                 BTREE_ITER_NOPRESERVE);
 352                 if (ret) {
 353                         ob = ERR_PTR(ret);
 354                         goto err;
 355                 }
 356
 357                 if (bp_offset != U64_MAX) {
 358                         /*
 359                          * Bucket may have data in it - we don't call
 360                          * bc2h_trans_inconnsistent() because fsck hasn't
 361                          * finished yet
 362                          */
 363                         ob = NULL;
 364                         goto err;
 365                 }
 366         }
 367
 368         ob = __try_alloc_bucket(c, ca, b, reserve, a, s, cl);
 369         if (!ob)
 370                 iter.path->preserve = false;
 371 err:
 372         set_btree_iter_dontneed(&iter);
 373         bch2_trans_iter_exit(trans, &iter);
 374         printbuf_exit(&buf);
 375         return ob;
 376 }
 377
 378 static struct open_bucket *try_alloc_partial_bucket(struct bch_fs *c, struct bch_dev *ca,
 379                                                     enum alloc_reserve reserve)
 380 {
 381         struct open_bucket *ob;
 382         int i;
 383
 384         spin_lock(&c->freelist_lock);
 385
 386         for (i = ca->open_buckets_partial_nr - 1; i >= 0; --i) {
 387                 ob = c->open_buckets + ca->open_buckets_partial[i];
 388
 389                 if (reserve <= ob->alloc_reserve) {
 390                         array_remove_item(ca->open_buckets_partial,
 391                                           ca->open_buckets_partial_nr,
 392                                           i);
 393                         ob->on_partial_list = false;
 394                         ob->alloc_reserve = reserve;
 395                         spin_unlock(&c->freelist_lock);
 396                         return ob;
 397                 }
 398         }
 399
 400         spin_unlock(&c->freelist_lock);
 401         return NULL;
 402 }
 403
 404 /*
 405  * This path is for before the freespace btree is initialized:
 406  *
 407  * If ca->new_fs_bucket_idx is nonzero, we haven't yet marked superblock &
 408  * journal buckets - journal buckets will be < ca->new_fs_bucket_idx
 409  */
 410 static noinline struct open_bucket *
 411 bch2_bucket_alloc_early(struct btree_trans *trans,
 412                         struct bch_dev *ca,
 413                         enum alloc_reserve reserve,
 414                         struct bucket_alloc_state *s,
 415                         struct closure *cl)
 416 {
 417         struct btree_iter iter;
 418         struct bkey_s_c k;
 419         struct open_bucket *ob = NULL;
 420         int ret;
 421
 422         s->cur_bucket = max_t(u64, s->cur_bucket, ca->mi.first_bucket);
 423         s->cur_bucket = max_t(u64, s->cur_bucket, ca->new_fs_bucket_idx);
 424
 425         for_each_btree_key_norestart(trans, iter, BTREE_ID_alloc, POS(ca->dev_idx, s->cur_bucket),
 426                            BTREE_ITER_SLOTS, k, ret) {
 427                 struct bch_alloc_v4 a_convert;
 428                 const struct bch_alloc_v4 *a;
 429
 430                 if (bkey_ge(k.k->p, POS(ca->dev_idx, ca->mi.nbuckets)))
 431                         break;
 432
 433                 if (ca->new_fs_bucket_idx &&
 434                     is_superblock_bucket(ca, k.k->p.offset))
 435                         continue;
 436
 437                 a = bch2_alloc_to_v4(k, &a_convert);
 438
 439                 if (a->data_type != BCH_DATA_free)
 440                         continue;
 441
 442                 s->buckets_seen++;
 443
 444                 ob = __try_alloc_bucket(trans->c, ca, k.k->p.offset, reserve, a, s, cl);
 445                 if (ob)
 446                         break;
 447         }
 448         bch2_trans_iter_exit(trans, &iter);
 449
 450         s->cur_bucket = iter.pos.offset;
 451
 452         return ob ?: ERR_PTR(ret ?: -BCH_ERR_no_buckets_found);
 453 }
 454
 455 static struct open_bucket *bch2_bucket_alloc_freelist(struct btree_trans *trans,
 456                                                    struct bch_dev *ca,
 457                                                    enum alloc_reserve reserve,
 458                                                    struct bucket_alloc_state *s,
 459                                                    struct closure *cl)
 460 {
 461         struct btree_iter iter;
 462         struct bkey_s_c k;
 463         struct open_bucket *ob = NULL;
 464         int ret;
 465
 466         BUG_ON(ca->new_fs_bucket_idx);
 467
 468         /*
 469          * XXX:
 470          * On transaction restart, we'd like to restart from the bucket we were
 471          * at previously
 472          */
 473         for_each_btree_key_norestart(trans, iter, BTREE_ID_freespace,
 474                                      POS(ca->dev_idx, s->cur_bucket), 0, k, ret) {
 475                 if (k.k->p.inode != ca->dev_idx)
 476                         break;
 477
 478                 for (s->cur_bucket = max(s->cur_bucket, bkey_start_offset(k.k));
 479                      s->cur_bucket < k.k->p.offset;
 480                      s->cur_bucket++) {
 481                         ret = btree_trans_too_many_iters(trans);
 482                         if (ret)
 483                                 break;
 484
 485                         s->buckets_seen++;
 486
 487                         ob = try_alloc_bucket(trans, ca, reserve,
 488                                               s->cur_bucket, s, k, cl);
 489                         if (ob)
 490                                 break;
 491                 }
 492
 493                 if (ob || ret)
 494                         break;
 495         }
 496         bch2_trans_iter_exit(trans, &iter);
 497
 498         return ob ?: ERR_PTR(ret);
 499 }
 500
 501 /**
 502  * bch_bucket_alloc - allocate a single bucket from a specific device
 503  *
 504  * Returns index of bucket on success, 0 on failure
 505  */
 506 static struct open_bucket *bch2_bucket_alloc_trans(struct btree_trans *trans,
 507                                       struct bch_dev *ca,
 508                                       enum alloc_reserve reserve,
 509                                       bool may_alloc_partial,
 510                                       struct closure *cl,
 511                                       struct bch_dev_usage *usage)
 512 {
 513         struct bch_fs *c = trans->c;
 514         struct open_bucket *ob = NULL;
 515         bool freespace = READ_ONCE(ca->mi.freespace_initialized);
 516         u64 start = freespace ? 0 : ca->bucket_alloc_trans_early_cursor;
 517         u64 avail;
 518         struct bucket_alloc_state s = { .cur_bucket = start };
 519         bool waiting = false;
 520 again:
 521         bch2_dev_usage_read_fast(ca, usage);
 522         avail = dev_buckets_free(ca, *usage, reserve);
 523
 524         if (usage->d[BCH_DATA_need_discard].buckets > avail)
 525                 bch2_do_discards(c);
 526
 527         if (usage->d[BCH_DATA_need_gc_gens].buckets > avail)
 528                 bch2_do_gc_gens(c);
 529
 530         if (should_invalidate_buckets(ca, *usage))
 531                 bch2_do_invalidates(c);
 532
 533         if (!avail) {
 534                 if (cl && !waiting) {
 535                         closure_wait(&c->freelist_wait, cl);
 536                         waiting = true;
 537                         goto again;
 538                 }
 539
 540                 if (!c->blocked_allocate)
 541                         c->blocked_allocate = local_clock();
 542
 543                 ob = ERR_PTR(-BCH_ERR_freelist_empty);
 544                 goto err;
 545         }
 546
 547         if (waiting)
 548                 closure_wake_up(&c->freelist_wait);
 549
 550         if (may_alloc_partial) {
 551                 ob = try_alloc_partial_bucket(c, ca, reserve);
 552                 if (ob)
 553                         return ob;
 554         }
 555 alloc:
 556         ob = likely(freespace)
 557                 ? bch2_bucket_alloc_freelist(trans, ca, reserve, &s, cl)
 558                 : bch2_bucket_alloc_early(trans, ca, reserve, &s, cl);
 559
 560         if (s.skipped_need_journal_commit * 2 > avail)
 561                 bch2_journal_flush_async(&c->journal, NULL);
 562
 563         if (!ob && !freespace && start) {
 564                 start = s.cur_bucket = 0;
 565                 goto alloc;
 566         }
 567
 568         if (!ob && freespace && !test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
 569                 freespace = false;
 570                 goto alloc;
 571         }
 572
 573         if (!freespace)
 574                 ca->bucket_alloc_trans_early_cursor = s.cur_bucket;
 575 err:
 576         if (!ob)
 577                 ob = ERR_PTR(-BCH_ERR_no_buckets_found);
 578
 579         if (!IS_ERR(ob))
 580                 trace_and_count(c, bucket_alloc, ca, bch2_alloc_reserves[reserve],
 581                                 may_alloc_partial, ob->bucket);
 582         else if (!bch2_err_matches(PTR_ERR(ob), BCH_ERR_transaction_restart))
 583                 trace_and_count(c, bucket_alloc_fail,
 584                                 ca, bch2_alloc_reserves[reserve],
 585                                 usage->d[BCH_DATA_free].buckets,
 586                                 avail,
 587                                 bch2_copygc_wait_amount(c),
 588                                 c->copygc_wait - atomic64_read(&c->io_clock[WRITE].now),
 589                                 &s,
 590                                 cl == NULL,
 591                                 bch2_err_str(PTR_ERR(ob)));
 592
 593         return ob;
 594 }
 595
 596 struct open_bucket *bch2_bucket_alloc(struct bch_fs *c, struct bch_dev *ca,
 597                                       enum alloc_reserve reserve,
 598                                       bool may_alloc_partial,
 599                                       struct closure *cl)
 600 {
 601         struct bch_dev_usage usage;
 602         struct open_bucket *ob;
 603
 604         bch2_trans_do(c, NULL, NULL, 0,
 605                       PTR_ERR_OR_ZERO(ob = bch2_bucket_alloc_trans(&trans, ca, reserve,
 606                                                         may_alloc_partial, cl, &usage)));
 607         return ob;
 608 }
 609
 610 static int __dev_stripe_cmp(struct dev_stripe_state *stripe,
 611                             unsigned l, unsigned r)
 612 {
 613         return ((stripe->next_alloc[l] > stripe->next_alloc[r]) -
 614                 (stripe->next_alloc[l] < stripe->next_alloc[r]));
 615 }
 616
 617 #define dev_stripe_cmp(l, r) __dev_stripe_cmp(stripe, l, r)
 618
 619 struct dev_alloc_list bch2_dev_alloc_list(struct bch_fs *c,
 620                                           struct dev_stripe_state *stripe,
 621                                           struct bch_devs_mask *devs)
 622 {
 623         struct dev_alloc_list ret = { .nr = 0 };
 624         unsigned i;
 625
 626         for_each_set_bit(i, devs->d, BCH_SB_MEMBERS_MAX)
 627                 ret.devs[ret.nr++] = i;
 628
 629         bubble_sort(ret.devs, ret.nr, dev_stripe_cmp);
 630         return ret;
 631 }
 632
 633 static inline void bch2_dev_stripe_increment_inlined(struct bch_dev *ca,
 634                                struct dev_stripe_state *stripe,
 635                                struct bch_dev_usage *usage)
 636 {
 637         u64 *v = stripe->next_alloc + ca->dev_idx;
 638         u64 free_space = dev_buckets_available(ca, RESERVE_none);
 639         u64 free_space_inv = free_space
 640                 ? div64_u64(1ULL << 48, free_space)
 641                 : 1ULL << 48;
 642         u64 scale = *v / 4;
 643
 644         if (*v + free_space_inv >= *v)
 645                 *v += free_space_inv;
 646         else
 647                 *v = U64_MAX;
 648
 649         for (v = stripe->next_alloc;
 650              v < stripe->next_alloc + ARRAY_SIZE(stripe->next_alloc); v++)
 651                 *v = *v < scale ? 0 : *v - scale;
 652 }
 653
 654 void bch2_dev_stripe_increment(struct bch_dev *ca,
 655                                struct dev_stripe_state *stripe)
 656 {
 657         struct bch_dev_usage usage;
 658
 659         bch2_dev_usage_read_fast(ca, &usage);
 660         bch2_dev_stripe_increment_inlined(ca, stripe, &usage);
 661 }
 662
 663 #define BUCKET_MAY_ALLOC_PARTIAL        (1 << 0)
 664 #define BUCKET_ALLOC_USE_DURABILITY     (1 << 1)
 665
 666 static void add_new_bucket(struct bch_fs *c,
 667                            struct open_buckets *ptrs,
 668                            struct bch_devs_mask *devs_may_alloc,
 669                            unsigned *nr_effective,
 670                            bool *have_cache,
 671                            unsigned flags,
 672                            struct open_bucket *ob)
 673 {
 674         unsigned durability =
 675                 bch_dev_bkey_exists(c, ob->dev)->mi.durability;
 676
 677         __clear_bit(ob->dev, devs_may_alloc->d);
 678         *nr_effective   += (flags & BUCKET_ALLOC_USE_DURABILITY)
 679                 ? durability : 1;
 680         *have_cache     |= !durability;
 681
 682         ob_push(c, ptrs, ob);
 683 }
 684
 685 static int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
 686                       struct open_buckets *ptrs,
 687                       struct dev_stripe_state *stripe,
 688                       struct bch_devs_mask *devs_may_alloc,
 689                       unsigned nr_replicas,
 690                       unsigned *nr_effective,
 691                       bool *have_cache,
 692                       enum alloc_reserve reserve,
 693                       unsigned flags,
 694                       struct closure *cl)
 695 {
 696         struct bch_fs *c = trans->c;
 697         struct dev_alloc_list devs_sorted =
 698                 bch2_dev_alloc_list(c, stripe, devs_may_alloc);
 699         unsigned dev;
 700         struct bch_dev *ca;
 701         int ret = -BCH_ERR_insufficient_devices;
 702         unsigned i;
 703
 704         BUG_ON(*nr_effective >= nr_replicas);
 705
 706         for (i = 0; i < devs_sorted.nr; i++) {
 707                 struct bch_dev_usage usage;
 708                 struct open_bucket *ob;
 709
 710                 dev = devs_sorted.devs[i];
 711
 712                 rcu_read_lock();
 713                 ca = rcu_dereference(c->devs[dev]);
 714                 if (ca)
 715                         percpu_ref_get(&ca->ref);
 716                 rcu_read_unlock();
 717
 718                 if (!ca)
 719                         continue;
 720
 721                 if (!ca->mi.durability && *have_cache) {
 722                         percpu_ref_put(&ca->ref);
 723                         continue;
 724                 }
 725
 726                 ob = bch2_bucket_alloc_trans(trans, ca, reserve,
 727                                 flags & BUCKET_MAY_ALLOC_PARTIAL, cl, &usage);
 728                 if (!IS_ERR(ob))
 729                         bch2_dev_stripe_increment_inlined(ca, stripe, &usage);
 730                 percpu_ref_put(&ca->ref);
 731
 732                 if (IS_ERR(ob)) {
 733                         ret = PTR_ERR(ob);
 734                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart) || cl)
 735                                 break;
 736                         continue;
 737                 }
 738
 739                 add_new_bucket(c, ptrs, devs_may_alloc,
 740                                nr_effective, have_cache, flags, ob);
 741
 742                 if (*nr_effective >= nr_replicas) {
 743                         ret = 0;
 744                         break;
 745                 }
 746         }
 747
 748         return ret;
 749 }
 750
 751 int bch2_bucket_alloc_set(struct bch_fs *c,
 752                       struct open_buckets *ptrs,
 753                       struct dev_stripe_state *stripe,
 754                       struct bch_devs_mask *devs_may_alloc,
 755                       unsigned nr_replicas,
 756                       unsigned *nr_effective,
 757                       bool *have_cache,
 758                       enum alloc_reserve reserve,
 759                       unsigned flags,
 760                       struct closure *cl)
 761 {
 762         return bch2_trans_do(c, NULL, NULL, 0,
 763                       bch2_bucket_alloc_set_trans(&trans, ptrs, stripe,
 764                                               devs_may_alloc, nr_replicas,
 765                                               nr_effective, have_cache, reserve,
 766                                               flags, cl));
 767 }
 768
 769 /* Allocate from stripes: */
 770
 771 /*
 772  * if we can't allocate a new stripe because there are already too many
 773  * partially filled stripes, force allocating from an existing stripe even when
 774  * it's to a device we don't want:
 775  */
 776
 777 static int bucket_alloc_from_stripe(struct bch_fs *c,
 778                          struct open_buckets *ptrs,
 779                          struct write_point *wp,
 780                          struct bch_devs_mask *devs_may_alloc,
 781                          u16 target,
 782                          unsigned erasure_code,
 783                          unsigned nr_replicas,
 784                          unsigned *nr_effective,
 785                          bool *have_cache,
 786                          unsigned flags,
 787                          struct closure *cl)
 788 {
 789         struct dev_alloc_list devs_sorted;
 790         struct ec_stripe_head *h;
 791         struct open_bucket *ob;
 792         struct bch_dev *ca;
 793         unsigned i, ec_idx;
 794
 795         if (!erasure_code)
 796                 return 0;
 797
 798         if (nr_replicas < 2)
 799                 return 0;
 800
 801         if (ec_open_bucket(c, ptrs))
 802                 return 0;
 803
 804         h = bch2_ec_stripe_head_get(c, target, 0, nr_replicas - 1,
 805                                     wp == &c->copygc_write_point,
 806                                     cl);
 807         if (IS_ERR(h))
 808                 return -PTR_ERR(h);
 809         if (!h)
 810                 return 0;
 811
 812         devs_sorted = bch2_dev_alloc_list(c, &wp->stripe, devs_may_alloc);
 813
 814         for (i = 0; i < devs_sorted.nr; i++)
 815                 for (ec_idx = 0; ec_idx < h->s->nr_data; ec_idx++) {
 816                         if (!h->s->blocks[ec_idx])
 817                                 continue;
 818
 819                         ob = c->open_buckets + h->s->blocks[ec_idx];
 820                         if (ob->dev == devs_sorted.devs[i] &&
 821                             !test_and_set_bit(ec_idx, h->s->blocks_allocated))
 822                                 goto got_bucket;
 823                 }
 824         goto out_put_head;
 825 got_bucket:
 826         ca = bch_dev_bkey_exists(c, ob->dev);
 827
 828         ob->ec_idx      = ec_idx;
 829         ob->ec          = h->s;
 830
 831         add_new_bucket(c, ptrs, devs_may_alloc,
 832                        nr_effective, have_cache, flags, ob);
 833         atomic_inc(&h->s->pin);
 834 out_put_head:
 835         bch2_ec_stripe_head_put(c, h);
 836         return 0;
 837 }
 838
 839 /* Sector allocator */
 840
 841 static void get_buckets_from_writepoint(struct bch_fs *c,
 842                                         struct open_buckets *ptrs,
 843                                         struct write_point *wp,
 844                                         struct bch_devs_mask *devs_may_alloc,
 845                                         unsigned nr_replicas,
 846                                         unsigned *nr_effective,
 847                                         bool *have_cache,
 848                                         unsigned flags,
 849                                         bool need_ec)
 850 {
 851         struct open_buckets ptrs_skip = { .nr = 0 };
 852         struct open_bucket *ob;
 853         unsigned i;
 854
 855         open_bucket_for_each(c, &wp->ptrs, ob, i) {
 856                 struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
 857
 858                 if (*nr_effective < nr_replicas &&
 859                     test_bit(ob->dev, devs_may_alloc->d) &&
 860                     (ca->mi.durability ||
 861                      (wp->data_type == BCH_DATA_user && !*have_cache)) &&
 862                     (ob->ec || !need_ec)) {
 863                         add_new_bucket(c, ptrs, devs_may_alloc,
 864                                        nr_effective, have_cache,
 865                                        flags, ob);
 866                 } else {
 867                         ob_push(c, &ptrs_skip, ob);
 868                 }
 869         }
 870         wp->ptrs = ptrs_skip;
 871 }
 872
 873 static int open_bucket_add_buckets(struct btree_trans *trans,
 874                         struct open_buckets *ptrs,
 875                         struct write_point *wp,
 876                         struct bch_devs_list *devs_have,
 877                         u16 target,
 878                         unsigned erasure_code,
 879                         unsigned nr_replicas,
 880                         unsigned *nr_effective,
 881                         bool *have_cache,
 882                         enum alloc_reserve reserve,
 883                         unsigned flags,
 884                         struct closure *_cl)
 885 {
 886         struct bch_fs *c = trans->c;
 887         struct bch_devs_mask devs;
 888         struct open_bucket *ob;
 889         struct closure *cl = NULL;
 890         int ret;
 891         unsigned i;
 892
 893         rcu_read_lock();
 894         devs = target_rw_devs(c, wp->data_type, target);
 895         rcu_read_unlock();
 896
 897         /* Don't allocate from devices we already have pointers to: */
 898         for (i = 0; i < devs_have->nr; i++)
 899                 __clear_bit(devs_have->devs[i], devs.d);
 900
 901         open_bucket_for_each(c, ptrs, ob, i)
 902                 __clear_bit(ob->dev, devs.d);
 903
 904         if (erasure_code) {
 905                 if (!ec_open_bucket(c, ptrs)) {
 906                         get_buckets_from_writepoint(c, ptrs, wp, &devs,
 907                                                     nr_replicas, nr_effective,
 908                                                     have_cache, flags, true);
 909                         if (*nr_effective >= nr_replicas)
 910                                 return 0;
 911                 }
 912
 913                 if (!ec_open_bucket(c, ptrs)) {
 914                         ret = bucket_alloc_from_stripe(c, ptrs, wp, &devs,
 915                                                  target, erasure_code,
 916                                                  nr_replicas, nr_effective,
 917                                                  have_cache, flags, _cl);
 918                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||
 919                             bch2_err_matches(ret, BCH_ERR_freelist_empty) ||
 920                             bch2_err_matches(ret, BCH_ERR_open_buckets_empty))
 921                                 return ret;
 922                         if (*nr_effective >= nr_replicas)
 923                                 return 0;
 924                 }
 925         }
 926
 927         get_buckets_from_writepoint(c, ptrs, wp, &devs,
 928                                     nr_replicas, nr_effective,
 929                                     have_cache, flags, false);
 930         if (*nr_effective >= nr_replicas)
 931                 return 0;
 932
 933 retry_blocking:
 934         /*
 935          * Try nonblocking first, so that if one device is full we'll try from
 936          * other devices:
 937          */
 938         ret = bch2_bucket_alloc_set_trans(trans, ptrs, &wp->stripe, &devs,
 939                                 nr_replicas, nr_effective, have_cache,
 940                                 reserve, flags, cl);
 941         if (ret &&
 942             !bch2_err_matches(ret, BCH_ERR_transaction_restart) &&
 943             !bch2_err_matches(ret, BCH_ERR_insufficient_devices) &&
 944             !cl && _cl) {
 945                 cl = _cl;
 946                 goto retry_blocking;
 947         }
 948
 949         return ret;
 950 }
 951
 952 void bch2_open_buckets_stop_dev(struct bch_fs *c, struct bch_dev *ca,
 953                                 struct open_buckets *obs)
 954 {
 955         struct open_buckets ptrs = { .nr = 0 };
 956         struct open_bucket *ob, *ob2;
 957         unsigned i, j;
 958
 959         open_bucket_for_each(c, obs, ob, i) {
 960                 bool drop = !ca || ob->dev == ca->dev_idx;
 961
 962                 if (!drop && ob->ec) {
 963                         mutex_lock(&ob->ec->lock);
 964                         for (j = 0; j < ob->ec->new_stripe.key.v.nr_blocks; j++) {
 965                                 if (!ob->ec->blocks[j])
 966                                         continue;
 967
 968                                 ob2 = c->open_buckets + ob->ec->blocks[j];
 969                                 drop |= ob2->dev == ca->dev_idx;
 970                         }
 971                         mutex_unlock(&ob->ec->lock);
 972                 }
 973
 974                 if (drop)
 975                         bch2_open_bucket_put(c, ob);
 976                 else
 977                         ob_push(c, &ptrs, ob);
 978         }
 979
 980         *obs = ptrs;
 981 }
 982
 983 void bch2_writepoint_stop(struct bch_fs *c, struct bch_dev *ca,
 984                           struct write_point *wp)
 985 {
 986         mutex_lock(&wp->lock);
 987         bch2_open_buckets_stop_dev(c, ca, &wp->ptrs);
 988         mutex_unlock(&wp->lock);
 989 }
 990
 991 static inline struct hlist_head *writepoint_hash(struct bch_fs *c,
 992                                                  unsigned long write_point)
 993 {
 994         unsigned hash =
 995                 hash_long(write_point, ilog2(ARRAY_SIZE(c->write_points_hash)));
 996
 997         return &c->write_points_hash[hash];
 998 }
 999
1000 static struct write_point *__writepoint_find(struct hlist_head *head,
1001                                              unsigned long write_point)
1002 {
1003         struct write_point *wp;
1004
1005         rcu_read_lock();
1006         hlist_for_each_entry_rcu(wp, head, node)
1007                 if (wp->write_point == write_point)
1008                         goto out;
1009         wp = NULL;
1010 out:
1011         rcu_read_unlock();
1012         return wp;
1013 }
1014
1015 static inline bool too_many_writepoints(struct bch_fs *c, unsigned factor)
1016 {
1017         u64 stranded    = c->write_points_nr * c->bucket_size_max;
1018         u64 free        = bch2_fs_usage_read_short(c).free;
1019
1020         return stranded * factor > free;
1021 }
1022
1023 static bool try_increase_writepoints(struct bch_fs *c)
1024 {
1025         struct write_point *wp;
1026
1027         if (c->write_points_nr == ARRAY_SIZE(c->write_points) ||
1028             too_many_writepoints(c, 32))
1029                 return false;
1030
1031         wp = c->write_points + c->write_points_nr++;
1032         hlist_add_head_rcu(&wp->node, writepoint_hash(c, wp->write_point));
1033         return true;
1034 }
1035
1036 static bool try_decrease_writepoints(struct bch_fs *c,
1037                                      unsigned old_nr)
1038 {
1039         struct write_point *wp;
1040
1041         mutex_lock(&c->write_points_hash_lock);
1042         if (c->write_points_nr < old_nr) {
1043                 mutex_unlock(&c->write_points_hash_lock);
1044                 return true;
1045         }
1046
1047         if (c->write_points_nr == 1 ||
1048             !too_many_writepoints(c, 8)) {
1049                 mutex_unlock(&c->write_points_hash_lock);
1050                 return false;
1051         }
1052
1053         wp = c->write_points + --c->write_points_nr;
1054
1055         hlist_del_rcu(&wp->node);
1056         mutex_unlock(&c->write_points_hash_lock);
1057
1058         bch2_writepoint_stop(c, NULL, wp);
1059         return true;
1060 }
1061
1062 static void bch2_trans_mutex_lock(struct btree_trans *trans,
1063                                   struct mutex *lock)
1064 {
1065         if (!mutex_trylock(lock)) {
1066                 bch2_trans_unlock(trans);
1067                 mutex_lock(lock);
1068         }
1069 }
1070
1071 static struct write_point *writepoint_find(struct btree_trans *trans,
1072                                            unsigned long write_point)
1073 {
1074         struct bch_fs *c = trans->c;
1075         struct write_point *wp, *oldest;
1076         struct hlist_head *head;
1077
1078         if (!(write_point & 1UL)) {
1079                 wp = (struct write_point *) write_point;
1080                 bch2_trans_mutex_lock(trans, &wp->lock);
1081                 return wp;
1082         }
1083
1084         head = writepoint_hash(c, write_point);
1085 restart_find:
1086         wp = __writepoint_find(head, write_point);
1087         if (wp) {
1088 lock_wp:
1089                 bch2_trans_mutex_lock(trans, &wp->lock);
1090                 if (wp->write_point == write_point)
1091                         goto out;
1092                 mutex_unlock(&wp->lock);
1093                 goto restart_find;
1094         }
1095 restart_find_oldest:
1096         oldest = NULL;
1097         for (wp = c->write_points;
1098              wp < c->write_points + c->write_points_nr; wp++)
1099                 if (!oldest || time_before64(wp->last_used, oldest->last_used))
1100                         oldest = wp;
1101
1102         bch2_trans_mutex_lock(trans, &oldest->lock);
1103         bch2_trans_mutex_lock(trans, &c->write_points_hash_lock);
1104         if (oldest >= c->write_points + c->write_points_nr ||
1105             try_increase_writepoints(c)) {
1106                 mutex_unlock(&c->write_points_hash_lock);
1107                 mutex_unlock(&oldest->lock);
1108                 goto restart_find_oldest;
1109         }
1110
1111         wp = __writepoint_find(head, write_point);
1112         if (wp && wp != oldest) {
1113                 mutex_unlock(&c->write_points_hash_lock);
1114                 mutex_unlock(&oldest->lock);
1115                 goto lock_wp;
1116         }
1117
1118         wp = oldest;
1119         hlist_del_rcu(&wp->node);
1120         wp->write_point = write_point;
1121         hlist_add_head_rcu(&wp->node, head);
1122         mutex_unlock(&c->write_points_hash_lock);
1123 out:
1124         wp->last_used = local_clock();
1125         return wp;
1126 }
1127
1128 /*
1129  * Get us an open_bucket we can allocate from, return with it locked:
1130  */
1131 int bch2_alloc_sectors_start_trans(struct btree_trans *trans,
1132                                    unsigned target,
1133                                    unsigned erasure_code,
1134                                    struct write_point_specifier write_point,
1135                                    struct bch_devs_list *devs_have,
1136                                    unsigned nr_replicas,
1137                                    unsigned nr_replicas_required,
1138                                    enum alloc_reserve reserve,
1139                                    unsigned flags,
1140                                    struct closure *cl,
1141                                    struct write_point **wp_ret)
1142 {
1143         struct bch_fs *c = trans->c;
1144         struct write_point *wp;
1145         struct open_bucket *ob;
1146         struct open_buckets ptrs;
1147         unsigned nr_effective, write_points_nr;
1148         unsigned ob_flags = 0;
1149         bool have_cache;
1150         int ret;
1151         int i;
1152
1153         if (!(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS))
1154                 ob_flags |= BUCKET_ALLOC_USE_DURABILITY;
1155
1156         BUG_ON(!nr_replicas || !nr_replicas_required);
1157 retry:
1158         ptrs.nr         = 0;
1159         nr_effective    = 0;
1160         write_points_nr = c->write_points_nr;
1161         have_cache      = false;
1162
1163         *wp_ret = wp = writepoint_find(trans, write_point.v);
1164
1165         if (wp->data_type == BCH_DATA_user)
1166                 ob_flags |= BUCKET_MAY_ALLOC_PARTIAL;
1167
1168         /* metadata may not allocate on cache devices: */
1169         if (wp->data_type != BCH_DATA_user)
1170                 have_cache = true;
1171
1172         if (!target || (flags & BCH_WRITE_ONLY_SPECIFIED_DEVS)) {
1173                 ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
1174                                               target, erasure_code,
1175                                               nr_replicas, &nr_effective,
1176                                               &have_cache, reserve,
1177                                               ob_flags, cl);
1178         } else {
1179                 ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
1180                                               target, erasure_code,
1181                                               nr_replicas, &nr_effective,
1182                                               &have_cache, reserve,
1183                                               ob_flags, NULL);
1184                 if (!ret ||
1185                     bch2_err_matches(ret, BCH_ERR_transaction_restart))
1186                         goto alloc_done;
1187
1188                 ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
1189                                               0, erasure_code,
1190                                               nr_replicas, &nr_effective,
1191                                               &have_cache, reserve,
1192                                               ob_flags, cl);
1193         }
1194 alloc_done:
1195         BUG_ON(!ret && nr_effective < nr_replicas);
1196
1197         if (erasure_code && !ec_open_bucket(c, &ptrs))
1198                 pr_debug("failed to get ec bucket: ret %u", ret);
1199
1200         if (ret == -BCH_ERR_insufficient_devices &&
1201             nr_effective >= nr_replicas_required)
1202                 ret = 0;
1203
1204         if (ret)
1205                 goto err;
1206
1207         /* Free buckets we didn't use: */
1208         open_bucket_for_each(c, &wp->ptrs, ob, i)
1209                 open_bucket_free_unused(c, wp, ob);
1210
1211         wp->ptrs = ptrs;
1212
1213         wp->sectors_free = UINT_MAX;
1214
1215         open_bucket_for_each(c, &wp->ptrs, ob, i)
1216                 wp->sectors_free = min(wp->sectors_free, ob->sectors_free);
1217
1218         BUG_ON(!wp->sectors_free || wp->sectors_free == UINT_MAX);
1219
1220         return 0;
1221 err:
1222         open_bucket_for_each(c, &wp->ptrs, ob, i)
1223                 if (ptrs.nr < ARRAY_SIZE(ptrs.v))
1224                         ob_push(c, &ptrs, ob);
1225                 else
1226                         open_bucket_free_unused(c, wp, ob);
1227         wp->ptrs = ptrs;
1228
1229         mutex_unlock(&wp->lock);
1230
1231         if (bch2_err_matches(ret, BCH_ERR_freelist_empty) &&
1232             try_decrease_writepoints(c, write_points_nr))
1233                 goto retry;
1234
1235         if (bch2_err_matches(ret, BCH_ERR_open_buckets_empty) ||
1236             bch2_err_matches(ret, BCH_ERR_freelist_empty))
1237                 return cl
1238                         ? -BCH_ERR_bucket_alloc_blocked
1239                         : -BCH_ERR_ENOSPC_bucket_alloc;
1240
1241         return ret;
1242 }
1243
1244 struct bch_extent_ptr bch2_ob_ptr(struct bch_fs *c, struct open_bucket *ob)
1245 {
1246         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
1247
1248         return (struct bch_extent_ptr) {
1249                 .type   = 1 << BCH_EXTENT_ENTRY_ptr,
1250                 .gen    = ob->gen,
1251                 .dev    = ob->dev,
1252                 .offset = bucket_to_sector(ca, ob->bucket) +
1253                         ca->mi.bucket_size -
1254                         ob->sectors_free,
1255         };
1256 }
1257
1258 void bch2_alloc_sectors_append_ptrs(struct bch_fs *c, struct write_point *wp,
1259                                     struct bkey_i *k, unsigned sectors,
1260                                     bool cached)
1261 {
1262         bch2_alloc_sectors_append_ptrs_inlined(c, wp, k, sectors, cached);
1263 }
1264
1265 /*
1266  * Append pointers to the space we just allocated to @k, and mark @sectors space
1267  * as allocated out of @ob
1268  */
1269 void bch2_alloc_sectors_done(struct bch_fs *c, struct write_point *wp)
1270 {
1271         bch2_alloc_sectors_done_inlined(c, wp);
1272 }
1273
1274 static inline void writepoint_init(struct write_point *wp,
1275                                    enum bch_data_type type)
1276 {
1277         mutex_init(&wp->lock);
1278         wp->data_type = type;
1279
1280         INIT_WORK(&wp->index_update_work, bch2_write_point_do_index_updates);
1281         INIT_LIST_HEAD(&wp->writes);
1282         spin_lock_init(&wp->writes_lock);
1283 }
1284
1285 void bch2_fs_allocator_foreground_init(struct bch_fs *c)
1286 {
1287         struct open_bucket *ob;
1288         struct write_point *wp;
1289
1290         mutex_init(&c->write_points_hash_lock);
1291         c->write_points_nr = ARRAY_SIZE(c->write_points);
1292
1293         /* open bucket 0 is a sentinal NULL: */
1294         spin_lock_init(&c->open_buckets[0].lock);
1295
1296         for (ob = c->open_buckets + 1;
1297              ob < c->open_buckets + ARRAY_SIZE(c->open_buckets); ob++) {
1298                 spin_lock_init(&ob->lock);
1299                 c->open_buckets_nr_free++;
1300
1301                 ob->freelist = c->open_buckets_freelist;
1302                 c->open_buckets_freelist = ob - c->open_buckets;
1303         }
1304
1305         writepoint_init(&c->btree_write_point,          BCH_DATA_btree);
1306         writepoint_init(&c->rebalance_write_point,      BCH_DATA_user);
1307         writepoint_init(&c->copygc_write_point,         BCH_DATA_user);
1308
1309         for (wp = c->write_points;
1310              wp < c->write_points + c->write_points_nr; wp++) {
1311                 writepoint_init(wp, BCH_DATA_user);
1312
1313                 wp->last_used   = local_clock();
1314                 wp->write_point = (unsigned long) wp;
1315                 hlist_add_head_rcu(&wp->node,
1316                                    writepoint_hash(c, wp->write_point));
1317         }
1318 }
1319
1320 void bch2_open_buckets_to_text(struct printbuf *out, struct bch_fs *c)
1321 {
1322         struct open_bucket *ob;
1323
1324         for (ob = c->open_buckets;
1325              ob < c->open_buckets + ARRAY_SIZE(c->open_buckets);
1326              ob++) {
1327                 spin_lock(&ob->lock);
1328                 if (ob->valid && !ob->on_partial_list) {
1329                         prt_printf(out, "%zu ref %u type %s %u:%llu:%u\n",
1330                                ob - c->open_buckets,
1331                                atomic_read(&ob->pin),
1332                                bch2_data_types[ob->data_type],
1333                                ob->dev, ob->bucket, ob->gen);
1334                 }
1335                 spin_unlock(&ob->lock);
1336         }
1337 }