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 #include "nocow_locking.h"
  32 #include "trace.h"
  33
  34 #include <linux/math64.h>
  35 #include <linux/rculist.h>
  36 #include <linux/rcupdate.h>
  37
  38 static void bch2_trans_mutex_lock_norelock(struct btree_trans *trans,
  39                                            struct mutex *lock)
  40 {
  41         if (!mutex_trylock(lock)) {
  42                 bch2_trans_unlock(trans);
  43                 mutex_lock(lock);
  44         }
  45 }
  46
  47 const char * const bch2_watermarks[] = {
  48 #define x(t) #t,
  49         BCH_WATERMARKS()
  50 #undef x
  51         NULL
  52 };
  53
  54 /*
  55  * Open buckets represent a bucket that's currently being allocated from.  They
  56  * serve two purposes:
  57  *
  58  *  - They track buckets that have been partially allocated, allowing for
  59  *    sub-bucket sized allocations - they're used by the sector allocator below
  60  *
  61  *  - They provide a reference to the buckets they own that mark and sweep GC
  62  *    can find, until the new allocation has a pointer to it inserted into the
  63  *    btree
  64  *
  65  * When allocating some space with the sector allocator, the allocation comes
  66  * with a reference to an open bucket - the caller is required to put that
  67  * reference _after_ doing the index update that makes its allocation reachable.
  68  */
  69
  70 void bch2_reset_alloc_cursors(struct bch_fs *c)
  71 {
  72         struct bch_dev *ca;
  73         unsigned i;
  74
  75         rcu_read_lock();
  76         for_each_member_device_rcu(ca, c, i, NULL)
  77                 ca->alloc_cursor = 0;
  78         rcu_read_unlock();
  79 }
  80
  81 static void bch2_open_bucket_hash_add(struct bch_fs *c, struct open_bucket *ob)
  82 {
  83         open_bucket_idx_t idx = ob - c->open_buckets;
  84         open_bucket_idx_t *slot = open_bucket_hashslot(c, ob->dev, ob->bucket);
  85
  86         ob->hash = *slot;
  87         *slot = idx;
  88 }
  89
  90 static void bch2_open_bucket_hash_remove(struct bch_fs *c, struct open_bucket *ob)
  91 {
  92         open_bucket_idx_t idx = ob - c->open_buckets;
  93         open_bucket_idx_t *slot = open_bucket_hashslot(c, ob->dev, ob->bucket);
  94
  95         while (*slot != idx) {
  96                 BUG_ON(!*slot);
  97                 slot = &c->open_buckets[*slot].hash;
  98         }
  99
 100         *slot = ob->hash;
 101         ob->hash = 0;
 102 }
 103
 104 void __bch2_open_bucket_put(struct bch_fs *c, struct open_bucket *ob)
 105 {
 106         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
 107
 108         if (ob->ec) {
 109                 ec_stripe_new_put(c, ob->ec, STRIPE_REF_io);
 110                 return;
 111         }
 112
 113         percpu_down_read(&c->mark_lock);
 114         spin_lock(&ob->lock);
 115
 116         ob->valid = false;
 117         ob->data_type = 0;
 118
 119         spin_unlock(&ob->lock);
 120         percpu_up_read(&c->mark_lock);
 121
 122         spin_lock(&c->freelist_lock);
 123         bch2_open_bucket_hash_remove(c, ob);
 124
 125         ob->freelist = c->open_buckets_freelist;
 126         c->open_buckets_freelist = ob - c->open_buckets;
 127
 128         c->open_buckets_nr_free++;
 129         ca->nr_open_buckets--;
 130         spin_unlock(&c->freelist_lock);
 131
 132         closure_wake_up(&c->open_buckets_wait);
 133 }
 134
 135 void bch2_open_bucket_write_error(struct bch_fs *c,
 136                                   struct open_buckets *obs,
 137                                   unsigned dev)
 138 {
 139         struct open_bucket *ob;
 140         unsigned i;
 141
 142         open_bucket_for_each(c, obs, ob, i)
 143                 if (ob->dev == dev && ob->ec)
 144                         bch2_ec_bucket_cancel(c, ob);
 145 }
 146
 147 static struct open_bucket *bch2_open_bucket_alloc(struct bch_fs *c)
 148 {
 149         struct open_bucket *ob;
 150
 151         BUG_ON(!c->open_buckets_freelist || !c->open_buckets_nr_free);
 152
 153         ob = c->open_buckets + c->open_buckets_freelist;
 154         c->open_buckets_freelist = ob->freelist;
 155         atomic_set(&ob->pin, 1);
 156         ob->data_type = 0;
 157
 158         c->open_buckets_nr_free--;
 159         return ob;
 160 }
 161
 162 static void open_bucket_free_unused(struct bch_fs *c, struct open_bucket *ob)
 163 {
 164         BUG_ON(c->open_buckets_partial_nr >=
 165                ARRAY_SIZE(c->open_buckets_partial));
 166
 167         spin_lock(&c->freelist_lock);
 168         ob->on_partial_list = true;
 169         c->open_buckets_partial[c->open_buckets_partial_nr++] =
 170                 ob - c->open_buckets;
 171         spin_unlock(&c->freelist_lock);
 172
 173         closure_wake_up(&c->open_buckets_wait);
 174         closure_wake_up(&c->freelist_wait);
 175 }
 176
 177 /* _only_ for allocating the journal on a new device: */
 178 long bch2_bucket_alloc_new_fs(struct bch_dev *ca)
 179 {
 180         while (ca->new_fs_bucket_idx < ca->mi.nbuckets) {
 181                 u64 b = ca->new_fs_bucket_idx++;
 182
 183                 if (!is_superblock_bucket(ca, b) &&
 184                     (!ca->buckets_nouse || !test_bit(b, ca->buckets_nouse)))
 185                         return b;
 186         }
 187
 188         return -1;
 189 }
 190
 191 static inline unsigned open_buckets_reserved(enum bch_watermark watermark)
 192 {
 193         switch (watermark) {
 194         case BCH_WATERMARK_btree:
 195         case BCH_WATERMARK_btree_copygc:
 196                 return 0;
 197         case BCH_WATERMARK_copygc:
 198                 return OPEN_BUCKETS_COUNT / 4;
 199         default:
 200                 return OPEN_BUCKETS_COUNT / 2;
 201         }
 202 }
 203
 204 static struct open_bucket *__try_alloc_bucket(struct bch_fs *c, struct bch_dev *ca,
 205                                               u64 bucket,
 206                                               enum bch_watermark watermark,
 207                                               const struct bch_alloc_v4 *a,
 208                                               struct bucket_alloc_state *s,
 209                                               struct closure *cl)
 210 {
 211         struct open_bucket *ob;
 212
 213         if (unlikely(ca->buckets_nouse && test_bit(bucket, ca->buckets_nouse))) {
 214                 s->skipped_nouse++;
 215                 return NULL;
 216         }
 217
 218         if (bch2_bucket_is_open(c, ca->dev_idx, bucket)) {
 219                 s->skipped_open++;
 220                 return NULL;
 221         }
 222
 223         if (bch2_bucket_needs_journal_commit(&c->buckets_waiting_for_journal,
 224                         c->journal.flushed_seq_ondisk, ca->dev_idx, bucket)) {
 225                 s->skipped_need_journal_commit++;
 226                 return NULL;
 227         }
 228
 229         if (bch2_bucket_nocow_is_locked(&c->nocow_locks, POS(ca->dev_idx, bucket))) {
 230                 s->skipped_nocow++;
 231                 return NULL;
 232         }
 233
 234         spin_lock(&c->freelist_lock);
 235
 236         if (unlikely(c->open_buckets_nr_free <= open_buckets_reserved(watermark))) {
 237                 if (cl)
 238                         closure_wait(&c->open_buckets_wait, cl);
 239
 240                 if (!c->blocked_allocate_open_bucket)
 241                         c->blocked_allocate_open_bucket = local_clock();
 242
 243                 spin_unlock(&c->freelist_lock);
 244                 return ERR_PTR(-BCH_ERR_open_buckets_empty);
 245         }
 246
 247         /* Recheck under lock: */
 248         if (bch2_bucket_is_open(c, ca->dev_idx, bucket)) {
 249                 spin_unlock(&c->freelist_lock);
 250                 s->skipped_open++;
 251                 return NULL;
 252         }
 253
 254         ob = bch2_open_bucket_alloc(c);
 255
 256         spin_lock(&ob->lock);
 257
 258         ob->valid       = true;
 259         ob->sectors_free = ca->mi.bucket_size;
 260         ob->dev         = ca->dev_idx;
 261         ob->gen         = a->gen;
 262         ob->bucket      = bucket;
 263         spin_unlock(&ob->lock);
 264
 265         ca->nr_open_buckets++;
 266         bch2_open_bucket_hash_add(c, ob);
 267
 268         if (c->blocked_allocate_open_bucket) {
 269                 bch2_time_stats_update(
 270                         &c->times[BCH_TIME_blocked_allocate_open_bucket],
 271                         c->blocked_allocate_open_bucket);
 272                 c->blocked_allocate_open_bucket = 0;
 273         }
 274
 275         if (c->blocked_allocate) {
 276                 bch2_time_stats_update(
 277                         &c->times[BCH_TIME_blocked_allocate],
 278                         c->blocked_allocate);
 279                 c->blocked_allocate = 0;
 280         }
 281
 282         spin_unlock(&c->freelist_lock);
 283         return ob;
 284 }
 285
 286 static struct open_bucket *try_alloc_bucket(struct btree_trans *trans, struct bch_dev *ca,
 287                                             enum bch_watermark watermark, u64 free_entry,
 288                                             struct bucket_alloc_state *s,
 289                                             struct bkey_s_c freespace_k,
 290                                             struct closure *cl)
 291 {
 292         struct bch_fs *c = trans->c;
 293         struct btree_iter iter = { NULL };
 294         struct bkey_s_c k;
 295         struct open_bucket *ob;
 296         struct bch_alloc_v4 a_convert;
 297         const struct bch_alloc_v4 *a;
 298         u64 b = free_entry & ~(~0ULL << 56);
 299         unsigned genbits = free_entry >> 56;
 300         struct printbuf buf = PRINTBUF;
 301         int ret;
 302
 303         if (b < ca->mi.first_bucket || b >= ca->mi.nbuckets) {
 304                 prt_printf(&buf, "freespace btree has bucket outside allowed range %u-%llu\n"
 305                        "  freespace key ",
 306                         ca->mi.first_bucket, ca->mi.nbuckets);
 307                 bch2_bkey_val_to_text(&buf, c, freespace_k);
 308                 bch2_trans_inconsistent(trans, "%s", buf.buf);
 309                 ob = ERR_PTR(-EIO);
 310                 goto err;
 311         }
 312
 313         k = bch2_bkey_get_iter(trans, &iter,
 314                                BTREE_ID_alloc, POS(ca->dev_idx, b),
 315                                BTREE_ITER_CACHED);
 316         ret = bkey_err(k);
 317         if (ret) {
 318                 ob = ERR_PTR(ret);
 319                 goto err;
 320         }
 321
 322         a = bch2_alloc_to_v4(k, &a_convert);
 323
 324         if (a->data_type != BCH_DATA_free) {
 325                 if (!test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
 326                         ob = NULL;
 327                         goto err;
 328                 }
 329
 330                 prt_printf(&buf, "non free bucket in freespace btree\n"
 331                        "  freespace key ");
 332                 bch2_bkey_val_to_text(&buf, c, freespace_k);
 333                 prt_printf(&buf, "\n  ");
 334                 bch2_bkey_val_to_text(&buf, c, k);
 335                 bch2_trans_inconsistent(trans, "%s", buf.buf);
 336                 ob = ERR_PTR(-EIO);
 337                 goto err;
 338         }
 339
 340         if (genbits != (alloc_freespace_genbits(*a) >> 56) &&
 341             test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
 342                 prt_printf(&buf, "bucket in freespace btree with wrong genbits (got %u should be %llu)\n"
 343                        "  freespace key ",
 344                        genbits, alloc_freespace_genbits(*a) >> 56);
 345                 bch2_bkey_val_to_text(&buf, c, freespace_k);
 346                 prt_printf(&buf, "\n  ");
 347                 bch2_bkey_val_to_text(&buf, c, k);
 348                 bch2_trans_inconsistent(trans, "%s", buf.buf);
 349                 ob = ERR_PTR(-EIO);
 350                 goto err;
 351
 352         }
 353
 354         if (!test_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags)) {
 355                 struct bch_backpointer bp;
 356                 struct bpos bp_pos = POS_MIN;
 357
 358                 ret = bch2_get_next_backpointer(trans, POS(ca->dev_idx, b), -1,
 359                                                 &bp_pos, &bp,
 360                                                 BTREE_ITER_NOPRESERVE);
 361                 if (ret) {
 362                         ob = ERR_PTR(ret);
 363                         goto err;
 364                 }
 365
 366                 if (!bkey_eq(bp_pos, POS_MAX)) {
 367                         /*
 368                          * Bucket may have data in it - we don't call
 369                          * bc2h_trans_inconnsistent() because fsck hasn't
 370                          * finished yet
 371                          */
 372                         ob = NULL;
 373                         goto err;
 374                 }
 375         }
 376
 377         ob = __try_alloc_bucket(c, ca, b, watermark, a, s, cl);
 378         if (!ob)
 379                 iter.path->preserve = false;
 380 err:
 381         if (iter.trans && iter.path)
 382                 set_btree_iter_dontneed(&iter);
 383         bch2_trans_iter_exit(trans, &iter);
 384         printbuf_exit(&buf);
 385         return ob;
 386 }
 387
 388 /*
 389  * This path is for before the freespace btree is initialized:
 390  *
 391  * If ca->new_fs_bucket_idx is nonzero, we haven't yet marked superblock &
 392  * journal buckets - journal buckets will be < ca->new_fs_bucket_idx
 393  */
 394 static noinline struct open_bucket *
 395 bch2_bucket_alloc_early(struct btree_trans *trans,
 396                         struct bch_dev *ca,
 397                         enum bch_watermark watermark,
 398                         struct bucket_alloc_state *s,
 399                         struct closure *cl)
 400 {
 401         struct btree_iter iter;
 402         struct bkey_s_c k;
 403         struct open_bucket *ob = NULL;
 404         u64 alloc_start = max_t(u64, ca->mi.first_bucket, ca->new_fs_bucket_idx);
 405         u64 alloc_cursor = max(alloc_start, READ_ONCE(ca->alloc_cursor));
 406         int ret;
 407 again:
 408         for_each_btree_key_norestart(trans, iter, BTREE_ID_alloc, POS(ca->dev_idx, alloc_cursor),
 409                            BTREE_ITER_SLOTS, k, ret) {
 410                 struct bch_alloc_v4 a_convert;
 411                 const struct bch_alloc_v4 *a;
 412
 413                 if (bkey_ge(k.k->p, POS(ca->dev_idx, ca->mi.nbuckets)))
 414                         break;
 415
 416                 if (ca->new_fs_bucket_idx &&
 417                     is_superblock_bucket(ca, k.k->p.offset))
 418                         continue;
 419
 420                 a = bch2_alloc_to_v4(k, &a_convert);
 421
 422                 if (a->data_type != BCH_DATA_free)
 423                         continue;
 424
 425                 s->buckets_seen++;
 426
 427                 ob = __try_alloc_bucket(trans->c, ca, k.k->p.offset, watermark, a, s, cl);
 428                 if (ob)
 429                         break;
 430         }
 431         bch2_trans_iter_exit(trans, &iter);
 432
 433         ca->alloc_cursor = alloc_cursor;
 434
 435         if (!ob && ret)
 436                 ob = ERR_PTR(ret);
 437
 438         if (!ob && alloc_cursor > alloc_start) {
 439                 alloc_cursor = alloc_start;
 440                 goto again;
 441         }
 442
 443         return ob;
 444 }
 445
 446 static struct open_bucket *bch2_bucket_alloc_freelist(struct btree_trans *trans,
 447                                                    struct bch_dev *ca,
 448                                                    enum bch_watermark watermark,
 449                                                    struct bucket_alloc_state *s,
 450                                                    struct closure *cl)
 451 {
 452         struct btree_iter iter;
 453         struct bkey_s_c k;
 454         struct open_bucket *ob = NULL;
 455         u64 alloc_start = max_t(u64, ca->mi.first_bucket, READ_ONCE(ca->alloc_cursor));
 456         u64 alloc_cursor = alloc_start;
 457         int ret;
 458
 459         BUG_ON(ca->new_fs_bucket_idx);
 460 again:
 461         for_each_btree_key_norestart(trans, iter, BTREE_ID_freespace,
 462                                      POS(ca->dev_idx, alloc_cursor), 0, k, ret) {
 463                 if (k.k->p.inode != ca->dev_idx)
 464                         break;
 465
 466                 for (alloc_cursor = max(alloc_cursor, bkey_start_offset(k.k));
 467                      alloc_cursor < k.k->p.offset;
 468                      alloc_cursor++) {
 469                         ret = btree_trans_too_many_iters(trans);
 470                         if (ret) {
 471                                 ob = ERR_PTR(ret);
 472                                 break;
 473                         }
 474
 475                         s->buckets_seen++;
 476
 477                         ob = try_alloc_bucket(trans, ca, watermark,
 478                                               alloc_cursor, s, k, cl);
 479                         if (ob) {
 480                                 iter.path->preserve = false;
 481                                 break;
 482                         }
 483                 }
 484
 485                 if (ob || ret)
 486                         break;
 487         }
 488         bch2_trans_iter_exit(trans, &iter);
 489
 490         ca->alloc_cursor = alloc_cursor;
 491
 492         if (!ob && ret)
 493                 ob = ERR_PTR(ret);
 494
 495         if (!ob && alloc_start > ca->mi.first_bucket) {
 496                 alloc_cursor = alloc_start = ca->mi.first_bucket;
 497                 goto again;
 498         }
 499
 500         return ob;
 501 }
 502
 503 /**
 504  * bch_bucket_alloc - allocate a single bucket from a specific device
 505  *
 506  * Returns index of bucket on success, 0 on failure
 507  */
 508 static struct open_bucket *bch2_bucket_alloc_trans(struct btree_trans *trans,
 509                                       struct bch_dev *ca,
 510                                       enum bch_watermark watermark,
 511                                       struct closure *cl,
 512                                       struct bch_dev_usage *usage)
 513 {
 514         struct bch_fs *c = trans->c;
 515         struct open_bucket *ob = NULL;
 516         bool freespace = READ_ONCE(ca->mi.freespace_initialized);
 517         u64 avail;
 518         struct bucket_alloc_state s = { 0 };
 519         bool waiting = false;
 520 again:
 521         bch2_dev_usage_read_fast(ca, usage);
 522         avail = dev_buckets_free(ca, *usage, watermark);
 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 alloc:
 550         ob = likely(freespace)
 551                 ? bch2_bucket_alloc_freelist(trans, ca, watermark, &s, cl)
 552                 : bch2_bucket_alloc_early(trans, ca, watermark, &s, cl);
 553
 554         if (s.skipped_need_journal_commit * 2 > avail)
 555                 bch2_journal_flush_async(&c->journal, NULL);
 556
 557         if (!ob && freespace && !test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
 558                 freespace = false;
 559                 goto alloc;
 560         }
 561 err:
 562         if (!ob)
 563                 ob = ERR_PTR(-BCH_ERR_no_buckets_found);
 564
 565         if (!IS_ERR(ob))
 566                 trace_and_count(c, bucket_alloc, ca,
 567                                 bch2_watermarks[watermark],
 568                                 ob->bucket,
 569                                 usage->d[BCH_DATA_free].buckets,
 570                                 avail,
 571                                 bch2_copygc_wait_amount(c),
 572                                 c->copygc_wait - atomic64_read(&c->io_clock[WRITE].now),
 573                                 &s,
 574                                 cl == NULL,
 575                                 "");
 576         else if (!bch2_err_matches(PTR_ERR(ob), BCH_ERR_transaction_restart))
 577                 trace_and_count(c, bucket_alloc_fail, ca,
 578                                 bch2_watermarks[watermark],
 579                                 0,
 580                                 usage->d[BCH_DATA_free].buckets,
 581                                 avail,
 582                                 bch2_copygc_wait_amount(c),
 583                                 c->copygc_wait - atomic64_read(&c->io_clock[WRITE].now),
 584                                 &s,
 585                                 cl == NULL,
 586                                 bch2_err_str(PTR_ERR(ob)));
 587
 588         return ob;
 589 }
 590
 591 struct open_bucket *bch2_bucket_alloc(struct bch_fs *c, struct bch_dev *ca,
 592                                       enum bch_watermark watermark,
 593                                       struct closure *cl)
 594 {
 595         struct bch_dev_usage usage;
 596         struct open_bucket *ob;
 597
 598         bch2_trans_do(c, NULL, NULL, 0,
 599                       PTR_ERR_OR_ZERO(ob = bch2_bucket_alloc_trans(&trans, ca, watermark,
 600                                                         cl, &usage)));
 601         return ob;
 602 }
 603
 604 static int __dev_stripe_cmp(struct dev_stripe_state *stripe,
 605                             unsigned l, unsigned r)
 606 {
 607         return ((stripe->next_alloc[l] > stripe->next_alloc[r]) -
 608                 (stripe->next_alloc[l] < stripe->next_alloc[r]));
 609 }
 610
 611 #define dev_stripe_cmp(l, r) __dev_stripe_cmp(stripe, l, r)
 612
 613 struct dev_alloc_list bch2_dev_alloc_list(struct bch_fs *c,
 614                                           struct dev_stripe_state *stripe,
 615                                           struct bch_devs_mask *devs)
 616 {
 617         struct dev_alloc_list ret = { .nr = 0 };
 618         unsigned i;
 619
 620         for_each_set_bit(i, devs->d, BCH_SB_MEMBERS_MAX)
 621                 ret.devs[ret.nr++] = i;
 622
 623         bubble_sort(ret.devs, ret.nr, dev_stripe_cmp);
 624         return ret;
 625 }
 626
 627 static inline void bch2_dev_stripe_increment_inlined(struct bch_dev *ca,
 628                                struct dev_stripe_state *stripe,
 629                                struct bch_dev_usage *usage)
 630 {
 631         u64 *v = stripe->next_alloc + ca->dev_idx;
 632         u64 free_space = dev_buckets_available(ca, BCH_WATERMARK_normal);
 633         u64 free_space_inv = free_space
 634                 ? div64_u64(1ULL << 48, free_space)
 635                 : 1ULL << 48;
 636         u64 scale = *v / 4;
 637
 638         if (*v + free_space_inv >= *v)
 639                 *v += free_space_inv;
 640         else
 641                 *v = U64_MAX;
 642
 643         for (v = stripe->next_alloc;
 644              v < stripe->next_alloc + ARRAY_SIZE(stripe->next_alloc); v++)
 645                 *v = *v < scale ? 0 : *v - scale;
 646 }
 647
 648 void bch2_dev_stripe_increment(struct bch_dev *ca,
 649                                struct dev_stripe_state *stripe)
 650 {
 651         struct bch_dev_usage usage;
 652
 653         bch2_dev_usage_read_fast(ca, &usage);
 654         bch2_dev_stripe_increment_inlined(ca, stripe, &usage);
 655 }
 656
 657 static int add_new_bucket(struct bch_fs *c,
 658                            struct open_buckets *ptrs,
 659                            struct bch_devs_mask *devs_may_alloc,
 660                            unsigned nr_replicas,
 661                            unsigned *nr_effective,
 662                            bool *have_cache,
 663                            unsigned flags,
 664                            struct open_bucket *ob)
 665 {
 666         unsigned durability =
 667                 bch_dev_bkey_exists(c, ob->dev)->mi.durability;
 668
 669         BUG_ON(*nr_effective >= nr_replicas);
 670         BUG_ON(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS);
 671
 672         __clear_bit(ob->dev, devs_may_alloc->d);
 673         *nr_effective   += (flags & BCH_WRITE_ONLY_SPECIFIED_DEVS)
 674                 ? durability : 1;
 675         *have_cache     |= !durability;
 676
 677         ob_push(c, ptrs, ob);
 678
 679         if (*nr_effective >= nr_replicas)
 680                 return 1;
 681         if (ob->ec)
 682                 return 1;
 683         return 0;
 684 }
 685
 686 int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
 687                       struct open_buckets *ptrs,
 688                       struct dev_stripe_state *stripe,
 689                       struct bch_devs_mask *devs_may_alloc,
 690                       unsigned nr_replicas,
 691                       unsigned *nr_effective,
 692                       bool *have_cache,
 693                       unsigned flags,
 694                       enum bch_data_type data_type,
 695                       enum bch_watermark watermark,
 696                       struct closure *cl)
 697 {
 698         struct bch_fs *c = trans->c;
 699         struct dev_alloc_list devs_sorted =
 700                 bch2_dev_alloc_list(c, stripe, devs_may_alloc);
 701         unsigned dev;
 702         struct bch_dev *ca;
 703         int ret = -BCH_ERR_insufficient_devices;
 704         unsigned i;
 705
 706         BUG_ON(*nr_effective >= nr_replicas);
 707
 708         for (i = 0; i < devs_sorted.nr; i++) {
 709                 struct bch_dev_usage usage;
 710                 struct open_bucket *ob;
 711
 712                 dev = devs_sorted.devs[i];
 713
 714                 rcu_read_lock();
 715                 ca = rcu_dereference(c->devs[dev]);
 716                 if (ca)
 717                         percpu_ref_get(&ca->ref);
 718                 rcu_read_unlock();
 719
 720                 if (!ca)
 721                         continue;
 722
 723                 if (!ca->mi.durability && *have_cache) {
 724                         percpu_ref_put(&ca->ref);
 725                         continue;
 726                 }
 727
 728                 ob = bch2_bucket_alloc_trans(trans, ca, watermark, cl, &usage);
 729                 if (!IS_ERR(ob))
 730                         bch2_dev_stripe_increment_inlined(ca, stripe, &usage);
 731                 percpu_ref_put(&ca->ref);
 732
 733                 if (IS_ERR(ob)) {
 734                         ret = PTR_ERR(ob);
 735                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart) || cl)
 736                                 break;
 737                         continue;
 738                 }
 739
 740                 ob->data_type = data_type;
 741
 742                 if (add_new_bucket(c, ptrs, devs_may_alloc,
 743                                    nr_replicas, nr_effective,
 744                                    have_cache, flags, ob)) {
 745                         ret = 0;
 746                         break;
 747                 }
 748         }
 749
 750         return ret;
 751 }
 752
 753 /* Allocate from stripes: */
 754
 755 /*
 756  * if we can't allocate a new stripe because there are already too many
 757  * partially filled stripes, force allocating from an existing stripe even when
 758  * it's to a device we don't want:
 759  */
 760
 761 static int bucket_alloc_from_stripe(struct btree_trans *trans,
 762                          struct open_buckets *ptrs,
 763                          struct write_point *wp,
 764                          struct bch_devs_mask *devs_may_alloc,
 765                          u16 target,
 766                          unsigned nr_replicas,
 767                          unsigned *nr_effective,
 768                          bool *have_cache,
 769                          enum bch_watermark watermark,
 770                          unsigned flags,
 771                          struct closure *cl)
 772 {
 773         struct bch_fs *c = trans->c;
 774         struct dev_alloc_list devs_sorted;
 775         struct ec_stripe_head *h;
 776         struct open_bucket *ob;
 777         struct bch_dev *ca;
 778         unsigned i, ec_idx;
 779         int ret = 0;
 780
 781         if (nr_replicas < 2)
 782                 return 0;
 783
 784         if (ec_open_bucket(c, ptrs))
 785                 return 0;
 786
 787         h = bch2_ec_stripe_head_get(trans, target, 0, nr_replicas - 1, watermark, cl);
 788         if (IS_ERR(h))
 789                 return PTR_ERR(h);
 790         if (!h)
 791                 return 0;
 792
 793         devs_sorted = bch2_dev_alloc_list(c, &wp->stripe, devs_may_alloc);
 794
 795         for (i = 0; i < devs_sorted.nr; i++)
 796                 for (ec_idx = 0; ec_idx < h->s->nr_data; ec_idx++) {
 797                         if (!h->s->blocks[ec_idx])
 798                                 continue;
 799
 800                         ob = c->open_buckets + h->s->blocks[ec_idx];
 801                         if (ob->dev == devs_sorted.devs[i] &&
 802                             !test_and_set_bit(ec_idx, h->s->blocks_allocated))
 803                                 goto got_bucket;
 804                 }
 805         goto out_put_head;
 806 got_bucket:
 807         ca = bch_dev_bkey_exists(c, ob->dev);
 808
 809         ob->ec_idx      = ec_idx;
 810         ob->ec          = h->s;
 811         ec_stripe_new_get(h->s, STRIPE_REF_io);
 812
 813         ret = add_new_bucket(c, ptrs, devs_may_alloc,
 814                              nr_replicas, nr_effective,
 815                              have_cache, flags, ob);
 816 out_put_head:
 817         bch2_ec_stripe_head_put(c, h);
 818         return ret;
 819 }
 820
 821 /* Sector allocator */
 822
 823 static bool want_bucket(struct bch_fs *c,
 824                         struct write_point *wp,
 825                         struct bch_devs_mask *devs_may_alloc,
 826                         bool *have_cache, bool ec,
 827                         struct open_bucket *ob)
 828 {
 829         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
 830
 831         if (!test_bit(ob->dev, devs_may_alloc->d))
 832                 return false;
 833
 834         if (ob->data_type != wp->data_type)
 835                 return false;
 836
 837         if (!ca->mi.durability &&
 838             (wp->data_type == BCH_DATA_btree || ec || *have_cache))
 839                 return false;
 840
 841         if (ec != (ob->ec != NULL))
 842                 return false;
 843
 844         return true;
 845 }
 846
 847 static int bucket_alloc_set_writepoint(struct bch_fs *c,
 848                                        struct open_buckets *ptrs,
 849                                        struct write_point *wp,
 850                                        struct bch_devs_mask *devs_may_alloc,
 851                                        unsigned nr_replicas,
 852                                        unsigned *nr_effective,
 853                                        bool *have_cache,
 854                                        bool ec, unsigned flags)
 855 {
 856         struct open_buckets ptrs_skip = { .nr = 0 };
 857         struct open_bucket *ob;
 858         unsigned i;
 859         int ret = 0;
 860
 861         open_bucket_for_each(c, &wp->ptrs, ob, i) {
 862                 if (!ret && want_bucket(c, wp, devs_may_alloc,
 863                                         have_cache, ec, ob))
 864                         ret = add_new_bucket(c, ptrs, devs_may_alloc,
 865                                        nr_replicas, nr_effective,
 866                                        have_cache, flags, ob);
 867                 else
 868                         ob_push(c, &ptrs_skip, ob);
 869         }
 870         wp->ptrs = ptrs_skip;
 871
 872         return ret;
 873 }
 874
 875 static int bucket_alloc_set_partial(struct bch_fs *c,
 876                                     struct open_buckets *ptrs,
 877                                     struct write_point *wp,
 878                                     struct bch_devs_mask *devs_may_alloc,
 879                                     unsigned nr_replicas,
 880                                     unsigned *nr_effective,
 881                                     bool *have_cache, bool ec,
 882                                     enum bch_watermark watermark,
 883                                     unsigned flags)
 884 {
 885         int i, ret = 0;
 886
 887         if (!c->open_buckets_partial_nr)
 888                 return 0;
 889
 890         spin_lock(&c->freelist_lock);
 891
 892         if (!c->open_buckets_partial_nr)
 893                 goto unlock;
 894
 895         for (i = c->open_buckets_partial_nr - 1; i >= 0; --i) {
 896                 struct open_bucket *ob = c->open_buckets + c->open_buckets_partial[i];
 897
 898                 if (want_bucket(c, wp, devs_may_alloc, have_cache, ec, ob)) {
 899                         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
 900                         struct bch_dev_usage usage;
 901                         u64 avail;
 902
 903                         bch2_dev_usage_read_fast(ca, &usage);
 904                         avail = dev_buckets_free(ca, usage, watermark);
 905                         if (!avail)
 906                                 continue;
 907
 908                         array_remove_item(c->open_buckets_partial,
 909                                           c->open_buckets_partial_nr,
 910                                           i);
 911                         ob->on_partial_list = false;
 912
 913                         ret = add_new_bucket(c, ptrs, devs_may_alloc,
 914                                              nr_replicas, nr_effective,
 915                                              have_cache, flags, ob);
 916                         if (ret)
 917                                 break;
 918                 }
 919         }
 920 unlock:
 921         spin_unlock(&c->freelist_lock);
 922         return ret;
 923 }
 924
 925 static int __open_bucket_add_buckets(struct btree_trans *trans,
 926                         struct open_buckets *ptrs,
 927                         struct write_point *wp,
 928                         struct bch_devs_list *devs_have,
 929                         u16 target,
 930                         bool erasure_code,
 931                         unsigned nr_replicas,
 932                         unsigned *nr_effective,
 933                         bool *have_cache,
 934                         enum bch_watermark watermark,
 935                         unsigned flags,
 936                         struct closure *_cl)
 937 {
 938         struct bch_fs *c = trans->c;
 939         struct bch_devs_mask devs;
 940         struct open_bucket *ob;
 941         struct closure *cl = NULL;
 942         unsigned i;
 943         int ret;
 944
 945         devs = target_rw_devs(c, wp->data_type, target);
 946
 947         /* Don't allocate from devices we already have pointers to: */
 948         for (i = 0; i < devs_have->nr; i++)
 949                 __clear_bit(devs_have->devs[i], devs.d);
 950
 951         open_bucket_for_each(c, ptrs, ob, i)
 952                 __clear_bit(ob->dev, devs.d);
 953
 954         if (erasure_code && ec_open_bucket(c, ptrs))
 955                 return 0;
 956
 957         ret = bucket_alloc_set_writepoint(c, ptrs, wp, &devs,
 958                                  nr_replicas, nr_effective,
 959                                  have_cache, erasure_code, flags);
 960         if (ret)
 961                 return ret;
 962
 963         ret = bucket_alloc_set_partial(c, ptrs, wp, &devs,
 964                                  nr_replicas, nr_effective,
 965                                  have_cache, erasure_code, watermark, flags);
 966         if (ret)
 967                 return ret;
 968
 969         if (erasure_code) {
 970                 ret = bucket_alloc_from_stripe(trans, ptrs, wp, &devs,
 971                                          target,
 972                                          nr_replicas, nr_effective,
 973                                          have_cache,
 974                                          watermark, flags, _cl);
 975         } else {
 976 retry_blocking:
 977                 /*
 978                  * Try nonblocking first, so that if one device is full we'll try from
 979                  * other devices:
 980                  */
 981                 ret = bch2_bucket_alloc_set_trans(trans, ptrs, &wp->stripe, &devs,
 982                                         nr_replicas, nr_effective, have_cache,
 983                                         flags, wp->data_type, watermark, cl);
 984                 if (ret &&
 985                     !bch2_err_matches(ret, BCH_ERR_transaction_restart) &&
 986                     !bch2_err_matches(ret, BCH_ERR_insufficient_devices) &&
 987                     !cl && _cl) {
 988                         cl = _cl;
 989                         goto retry_blocking;
 990                 }
 991
 992         }
 993
 994         return ret;
 995 }
 996
 997 static int open_bucket_add_buckets(struct btree_trans *trans,
 998                         struct open_buckets *ptrs,
 999                         struct write_point *wp,
1000                         struct bch_devs_list *devs_have,
1001                         u16 target,
1002                         unsigned erasure_code,
1003                         unsigned nr_replicas,
1004                         unsigned *nr_effective,
1005                         bool *have_cache,
1006                         enum bch_watermark watermark,
1007                         unsigned flags,
1008                         struct closure *cl)
1009 {
1010         int ret;
1011
1012         if (erasure_code) {
1013                 ret = __open_bucket_add_buckets(trans, ptrs, wp,
1014                                 devs_have, target, erasure_code,
1015                                 nr_replicas, nr_effective, have_cache,
1016                                 watermark, flags, cl);
1017                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||
1018                     bch2_err_matches(ret, BCH_ERR_operation_blocked) ||
1019                     bch2_err_matches(ret, BCH_ERR_freelist_empty) ||
1020                     bch2_err_matches(ret, BCH_ERR_open_buckets_empty))
1021                         return ret;
1022                 if (*nr_effective >= nr_replicas)
1023                         return 0;
1024         }
1025
1026         ret = __open_bucket_add_buckets(trans, ptrs, wp,
1027                         devs_have, target, false,
1028                         nr_replicas, nr_effective, have_cache,
1029                         watermark, flags, cl);
1030         return ret < 0 ? ret : 0;
1031 }
1032
1033 static bool should_drop_bucket(struct open_bucket *ob, struct bch_fs *c,
1034                                struct bch_dev *ca, bool ec)
1035 {
1036         if (ec) {
1037                 return ob->ec != NULL;
1038         } else if (ca) {
1039                 bool drop = ob->dev == ca->dev_idx;
1040                 struct open_bucket *ob2;
1041                 unsigned i;
1042
1043                 if (!drop && ob->ec) {
1044                         mutex_lock(&ob->ec->lock);
1045                         for (i = 0; i < ob->ec->new_stripe.key.v.nr_blocks; i++) {
1046                                 if (!ob->ec->blocks[i])
1047                                         continue;
1048
1049                                 ob2 = c->open_buckets + ob->ec->blocks[i];
1050                                 drop |= ob2->dev == ca->dev_idx;
1051                         }
1052                         mutex_unlock(&ob->ec->lock);
1053                 }
1054
1055                 return drop;
1056         } else {
1057                 return true;
1058         }
1059 }
1060
1061 static void bch2_writepoint_stop(struct bch_fs *c, struct bch_dev *ca,
1062                                  bool ec, struct write_point *wp)
1063 {
1064         struct open_buckets ptrs = { .nr = 0 };
1065         struct open_bucket *ob;
1066         unsigned i;
1067
1068         mutex_lock(&wp->lock);
1069         open_bucket_for_each(c, &wp->ptrs, ob, i)
1070                 if (should_drop_bucket(ob, c, ca, ec))
1071                         bch2_open_bucket_put(c, ob);
1072                 else
1073                         ob_push(c, &ptrs, ob);
1074         wp->ptrs = ptrs;
1075         mutex_unlock(&wp->lock);
1076 }
1077
1078 void bch2_open_buckets_stop(struct bch_fs *c, struct bch_dev *ca,
1079                             bool ec)
1080 {
1081         unsigned i;
1082
1083         /* Next, close write points that point to this device... */
1084         for (i = 0; i < ARRAY_SIZE(c->write_points); i++)
1085                 bch2_writepoint_stop(c, ca, ec, &c->write_points[i]);
1086
1087         bch2_writepoint_stop(c, ca, ec, &c->copygc_write_point);
1088         bch2_writepoint_stop(c, ca, ec, &c->rebalance_write_point);
1089         bch2_writepoint_stop(c, ca, ec, &c->btree_write_point);
1090
1091         mutex_lock(&c->btree_reserve_cache_lock);
1092         while (c->btree_reserve_cache_nr) {
1093                 struct btree_alloc *a =
1094                         &c->btree_reserve_cache[--c->btree_reserve_cache_nr];
1095
1096                 bch2_open_buckets_put(c, &a->ob);
1097         }
1098         mutex_unlock(&c->btree_reserve_cache_lock);
1099
1100         spin_lock(&c->freelist_lock);
1101         i = 0;
1102         while (i < c->open_buckets_partial_nr) {
1103                 struct open_bucket *ob =
1104                         c->open_buckets + c->open_buckets_partial[i];
1105
1106                 if (should_drop_bucket(ob, c, ca, ec)) {
1107                         --c->open_buckets_partial_nr;
1108                         swap(c->open_buckets_partial[i],
1109                              c->open_buckets_partial[c->open_buckets_partial_nr]);
1110                         ob->on_partial_list = false;
1111                         spin_unlock(&c->freelist_lock);
1112                         bch2_open_bucket_put(c, ob);
1113                         spin_lock(&c->freelist_lock);
1114                 } else {
1115                         i++;
1116                 }
1117         }
1118         spin_unlock(&c->freelist_lock);
1119
1120         bch2_ec_stop_dev(c, ca);
1121 }
1122
1123 static inline struct hlist_head *writepoint_hash(struct bch_fs *c,
1124                                                  unsigned long write_point)
1125 {
1126         unsigned hash =
1127                 hash_long(write_point, ilog2(ARRAY_SIZE(c->write_points_hash)));
1128
1129         return &c->write_points_hash[hash];
1130 }
1131
1132 static struct write_point *__writepoint_find(struct hlist_head *head,
1133                                              unsigned long write_point)
1134 {
1135         struct write_point *wp;
1136
1137         rcu_read_lock();
1138         hlist_for_each_entry_rcu(wp, head, node)
1139                 if (wp->write_point == write_point)
1140                         goto out;
1141         wp = NULL;
1142 out:
1143         rcu_read_unlock();
1144         return wp;
1145 }
1146
1147 static inline bool too_many_writepoints(struct bch_fs *c, unsigned factor)
1148 {
1149         u64 stranded    = c->write_points_nr * c->bucket_size_max;
1150         u64 free        = bch2_fs_usage_read_short(c).free;
1151
1152         return stranded * factor > free;
1153 }
1154
1155 static bool try_increase_writepoints(struct bch_fs *c)
1156 {
1157         struct write_point *wp;
1158
1159         if (c->write_points_nr == ARRAY_SIZE(c->write_points) ||
1160             too_many_writepoints(c, 32))
1161                 return false;
1162
1163         wp = c->write_points + c->write_points_nr++;
1164         hlist_add_head_rcu(&wp->node, writepoint_hash(c, wp->write_point));
1165         return true;
1166 }
1167
1168 static bool try_decrease_writepoints(struct btree_trans *trans, unsigned old_nr)
1169 {
1170         struct bch_fs *c = trans->c;
1171         struct write_point *wp;
1172         struct open_bucket *ob;
1173         unsigned i;
1174
1175         mutex_lock(&c->write_points_hash_lock);
1176         if (c->write_points_nr < old_nr) {
1177                 mutex_unlock(&c->write_points_hash_lock);
1178                 return true;
1179         }
1180
1181         if (c->write_points_nr == 1 ||
1182             !too_many_writepoints(c, 8)) {
1183                 mutex_unlock(&c->write_points_hash_lock);
1184                 return false;
1185         }
1186
1187         wp = c->write_points + --c->write_points_nr;
1188
1189         hlist_del_rcu(&wp->node);
1190         mutex_unlock(&c->write_points_hash_lock);
1191
1192         bch2_trans_mutex_lock_norelock(trans, &wp->lock);
1193         open_bucket_for_each(c, &wp->ptrs, ob, i)
1194                 open_bucket_free_unused(c, ob);
1195         mutex_unlock(&wp->lock);
1196         return true;
1197 }
1198
1199 static struct write_point *writepoint_find(struct btree_trans *trans,
1200                                            unsigned long write_point)
1201 {
1202         struct bch_fs *c = trans->c;
1203         struct write_point *wp, *oldest;
1204         struct hlist_head *head;
1205
1206         if (!(write_point & 1UL)) {
1207                 wp = (struct write_point *) write_point;
1208                 bch2_trans_mutex_lock_norelock(trans, &wp->lock);
1209                 return wp;
1210         }
1211
1212         head = writepoint_hash(c, write_point);
1213 restart_find:
1214         wp = __writepoint_find(head, write_point);
1215         if (wp) {
1216 lock_wp:
1217                 bch2_trans_mutex_lock_norelock(trans, &wp->lock);
1218                 if (wp->write_point == write_point)
1219                         goto out;
1220                 mutex_unlock(&wp->lock);
1221                 goto restart_find;
1222         }
1223 restart_find_oldest:
1224         oldest = NULL;
1225         for (wp = c->write_points;
1226              wp < c->write_points + c->write_points_nr; wp++)
1227                 if (!oldest || time_before64(wp->last_used, oldest->last_used))
1228                         oldest = wp;
1229
1230         bch2_trans_mutex_lock_norelock(trans, &oldest->lock);
1231         bch2_trans_mutex_lock_norelock(trans, &c->write_points_hash_lock);
1232         if (oldest >= c->write_points + c->write_points_nr ||
1233             try_increase_writepoints(c)) {
1234                 mutex_unlock(&c->write_points_hash_lock);
1235                 mutex_unlock(&oldest->lock);
1236                 goto restart_find_oldest;
1237         }
1238
1239         wp = __writepoint_find(head, write_point);
1240         if (wp && wp != oldest) {
1241                 mutex_unlock(&c->write_points_hash_lock);
1242                 mutex_unlock(&oldest->lock);
1243                 goto lock_wp;
1244         }
1245
1246         wp = oldest;
1247         hlist_del_rcu(&wp->node);
1248         wp->write_point = write_point;
1249         hlist_add_head_rcu(&wp->node, head);
1250         mutex_unlock(&c->write_points_hash_lock);
1251 out:
1252         wp->last_used = local_clock();
1253         return wp;
1254 }
1255
1256 /*
1257  * Get us an open_bucket we can allocate from, return with it locked:
1258  */
1259 int bch2_alloc_sectors_start_trans(struct btree_trans *trans,
1260                              unsigned target,
1261                              unsigned erasure_code,
1262                              struct write_point_specifier write_point,
1263                              struct bch_devs_list *devs_have,
1264                              unsigned nr_replicas,
1265                              unsigned nr_replicas_required,
1266                              enum bch_watermark watermark,
1267                              unsigned flags,
1268                              struct closure *cl,
1269                              struct write_point **wp_ret)
1270 {
1271         struct bch_fs *c = trans->c;
1272         struct write_point *wp;
1273         struct open_bucket *ob;
1274         struct open_buckets ptrs;
1275         unsigned nr_effective, write_points_nr;
1276         bool have_cache;
1277         int ret;
1278         int i;
1279
1280         BUG_ON(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS);
1281
1282         BUG_ON(!nr_replicas || !nr_replicas_required);
1283 retry:
1284         ptrs.nr         = 0;
1285         nr_effective    = 0;
1286         write_points_nr = c->write_points_nr;
1287         have_cache      = false;
1288
1289         *wp_ret = wp = writepoint_find(trans, write_point.v);
1290
1291         /* metadata may not allocate on cache devices: */
1292         if (wp->data_type != BCH_DATA_user)
1293                 have_cache = true;
1294
1295         if (target && !(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS)) {
1296                 ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
1297                                               target, erasure_code,
1298                                               nr_replicas, &nr_effective,
1299                                               &have_cache, watermark,
1300                                               flags, NULL);
1301                 if (!ret ||
1302                     bch2_err_matches(ret, BCH_ERR_transaction_restart))
1303                         goto alloc_done;
1304
1305                 /* Don't retry from all devices if we're out of open buckets: */
1306                 if (bch2_err_matches(ret, BCH_ERR_open_buckets_empty))
1307                         goto allocate_blocking;
1308
1309                 /*
1310                  * Only try to allocate cache (durability = 0 devices) from the
1311                  * specified target:
1312                  */
1313                 have_cache = true;
1314
1315                 ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
1316                                               0, erasure_code,
1317                                               nr_replicas, &nr_effective,
1318                                               &have_cache, watermark,
1319                                               flags, cl);
1320         } else {
1321 allocate_blocking:
1322                 ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
1323                                               target, erasure_code,
1324                                               nr_replicas, &nr_effective,
1325                                               &have_cache, watermark,
1326                                               flags, cl);
1327         }
1328 alloc_done:
1329         BUG_ON(!ret && nr_effective < nr_replicas);
1330
1331         if (erasure_code && !ec_open_bucket(c, &ptrs))
1332                 pr_debug("failed to get ec bucket: ret %u", ret);
1333
1334         if (ret == -BCH_ERR_insufficient_devices &&
1335             nr_effective >= nr_replicas_required)
1336                 ret = 0;
1337
1338         if (ret)
1339                 goto err;
1340
1341         /* Free buckets we didn't use: */
1342         open_bucket_for_each(c, &wp->ptrs, ob, i)
1343                 open_bucket_free_unused(c, ob);
1344
1345         wp->ptrs = ptrs;
1346
1347         wp->sectors_free = UINT_MAX;
1348
1349         open_bucket_for_each(c, &wp->ptrs, ob, i)
1350                 wp->sectors_free = min(wp->sectors_free, ob->sectors_free);
1351
1352         BUG_ON(!wp->sectors_free || wp->sectors_free == UINT_MAX);
1353
1354         return 0;
1355 err:
1356         open_bucket_for_each(c, &wp->ptrs, ob, i)
1357                 if (ptrs.nr < ARRAY_SIZE(ptrs.v))
1358                         ob_push(c, &ptrs, ob);
1359                 else
1360                         open_bucket_free_unused(c, ob);
1361         wp->ptrs = ptrs;
1362
1363         mutex_unlock(&wp->lock);
1364
1365         if (bch2_err_matches(ret, BCH_ERR_freelist_empty) &&
1366             try_decrease_writepoints(trans, write_points_nr))
1367                 goto retry;
1368
1369         if (bch2_err_matches(ret, BCH_ERR_open_buckets_empty) ||
1370             bch2_err_matches(ret, BCH_ERR_freelist_empty))
1371                 return cl
1372                         ? -BCH_ERR_bucket_alloc_blocked
1373                         : -BCH_ERR_ENOSPC_bucket_alloc;
1374
1375         return ret;
1376 }
1377
1378 struct bch_extent_ptr bch2_ob_ptr(struct bch_fs *c, struct open_bucket *ob)
1379 {
1380         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
1381
1382         return (struct bch_extent_ptr) {
1383                 .type   = 1 << BCH_EXTENT_ENTRY_ptr,
1384                 .gen    = ob->gen,
1385                 .dev    = ob->dev,
1386                 .offset = bucket_to_sector(ca, ob->bucket) +
1387                         ca->mi.bucket_size -
1388                         ob->sectors_free,
1389         };
1390 }
1391
1392 void bch2_alloc_sectors_append_ptrs(struct bch_fs *c, struct write_point *wp,
1393                                     struct bkey_i *k, unsigned sectors,
1394                                     bool cached)
1395 {
1396         bch2_alloc_sectors_append_ptrs_inlined(c, wp, k, sectors, cached);
1397 }
1398
1399 /*
1400  * Append pointers to the space we just allocated to @k, and mark @sectors space
1401  * as allocated out of @ob
1402  */
1403 void bch2_alloc_sectors_done(struct bch_fs *c, struct write_point *wp)
1404 {
1405         bch2_alloc_sectors_done_inlined(c, wp);
1406 }
1407
1408 static inline void writepoint_init(struct write_point *wp,
1409                                    enum bch_data_type type)
1410 {
1411         mutex_init(&wp->lock);
1412         wp->data_type = type;
1413
1414         INIT_WORK(&wp->index_update_work, bch2_write_point_do_index_updates);
1415         INIT_LIST_HEAD(&wp->writes);
1416         spin_lock_init(&wp->writes_lock);
1417 }
1418
1419 void bch2_fs_allocator_foreground_init(struct bch_fs *c)
1420 {
1421         struct open_bucket *ob;
1422         struct write_point *wp;
1423
1424         mutex_init(&c->write_points_hash_lock);
1425         c->write_points_nr = ARRAY_SIZE(c->write_points);
1426
1427         /* open bucket 0 is a sentinal NULL: */
1428         spin_lock_init(&c->open_buckets[0].lock);
1429
1430         for (ob = c->open_buckets + 1;
1431              ob < c->open_buckets + ARRAY_SIZE(c->open_buckets); ob++) {
1432                 spin_lock_init(&ob->lock);
1433                 c->open_buckets_nr_free++;
1434
1435                 ob->freelist = c->open_buckets_freelist;
1436                 c->open_buckets_freelist = ob - c->open_buckets;
1437         }
1438
1439         writepoint_init(&c->btree_write_point,          BCH_DATA_btree);
1440         writepoint_init(&c->rebalance_write_point,      BCH_DATA_user);
1441         writepoint_init(&c->copygc_write_point,         BCH_DATA_user);
1442
1443         for (wp = c->write_points;
1444              wp < c->write_points + c->write_points_nr; wp++) {
1445                 writepoint_init(wp, BCH_DATA_user);
1446
1447                 wp->last_used   = local_clock();
1448                 wp->write_point = (unsigned long) wp;
1449                 hlist_add_head_rcu(&wp->node,
1450                                    writepoint_hash(c, wp->write_point));
1451         }
1452 }
1453
1454 static void bch2_open_bucket_to_text(struct printbuf *out, struct bch_fs *c, struct open_bucket *ob)
1455 {
1456         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
1457         unsigned data_type = ob->data_type;
1458         barrier(); /* READ_ONCE() doesn't work on bitfields */
1459
1460         prt_printf(out, "%zu ref %u %s %u:%llu gen %u allocated %u/%u",
1461                    ob - c->open_buckets,
1462                    atomic_read(&ob->pin),
1463                    data_type < BCH_DATA_NR ? bch2_data_types[data_type] : "invalid data type",
1464                    ob->dev, ob->bucket, ob->gen,
1465                    ca->mi.bucket_size - ob->sectors_free, ca->mi.bucket_size);
1466         if (ob->ec)
1467                 prt_printf(out, " ec idx %llu", ob->ec->idx);
1468         if (ob->on_partial_list)
1469                 prt_str(out, " partial");
1470         prt_newline(out);
1471 }
1472
1473 void bch2_open_buckets_to_text(struct printbuf *out, struct bch_fs *c)
1474 {
1475         struct open_bucket *ob;
1476
1477         out->atomic++;
1478
1479         for (ob = c->open_buckets;
1480              ob < c->open_buckets + ARRAY_SIZE(c->open_buckets);
1481              ob++) {
1482                 spin_lock(&ob->lock);
1483                 if (ob->valid && !ob->on_partial_list)
1484                         bch2_open_bucket_to_text(out, c, ob);
1485                 spin_unlock(&ob->lock);
1486         }
1487
1488         --out->atomic;
1489 }
1490
1491 void bch2_open_buckets_partial_to_text(struct printbuf *out, struct bch_fs *c)
1492 {
1493         unsigned i;
1494
1495         out->atomic++;
1496         spin_lock(&c->freelist_lock);
1497
1498         for (i = 0; i < c->open_buckets_partial_nr; i++)
1499                 bch2_open_bucket_to_text(out, c,
1500                                 c->open_buckets + c->open_buckets_partial[i]);
1501
1502         spin_unlock(&c->freelist_lock);
1503         --out->atomic;
1504 }
1505
1506 static const char * const bch2_write_point_states[] = {
1507 #define x(n)    #n,
1508         WRITE_POINT_STATES()
1509 #undef x
1510         NULL
1511 };
1512
1513 void bch2_write_points_to_text(struct printbuf *out, struct bch_fs *c)
1514 {
1515         struct write_point *wp;
1516         unsigned i;
1517
1518         for (wp = c->write_points;
1519              wp < c->write_points + ARRAY_SIZE(c->write_points);
1520              wp++) {
1521                 prt_printf(out, "%lu: ", wp->write_point);
1522                 prt_human_readable_u64(out, wp->sectors_allocated);
1523
1524                 prt_printf(out, " last wrote: ");
1525                 bch2_pr_time_units(out, sched_clock() - wp->last_used);
1526
1527                 for (i = 0; i < WRITE_POINT_STATE_NR; i++) {
1528                         prt_printf(out, " %s: ", bch2_write_point_states[i]);
1529                         bch2_pr_time_units(out, wp->time[i]);
1530                 }
1531
1532                 prt_newline(out);
1533         }
1534 }