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[bcachefs-tools-debian] / 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 "btree_iter.h"
18 #include "btree_update.h"
19 #include "btree_gc.h"
20 #include "buckets.h"
21 #include "buckets_waiting_for_journal.h"
22 #include "clock.h"
23 #include "debug.h"
24 #include "disk_groups.h"
25 #include "ec.h"
26 #include "error.h"
27 #include "io.h"
28 #include "journal.h"
29 #include "movinggc.h"
30
31 #include <linux/math64.h>
32 #include <linux/rculist.h>
33 #include <linux/rcupdate.h>
34 #include <trace/events/bcachefs.h>
35
36 const char * const bch2_alloc_reserves[] = {
37 #define x(t) #t,
38         BCH_ALLOC_RESERVES()
39 #undef x
40         NULL
41 };
42
43 /*
44  * Open buckets represent a bucket that's currently being allocated from.  They
45  * serve two purposes:
46  *
47  *  - They track buckets that have been partially allocated, allowing for
48  *    sub-bucket sized allocations - they're used by the sector allocator below
49  *
50  *  - They provide a reference to the buckets they own that mark and sweep GC
51  *    can find, until the new allocation has a pointer to it inserted into the
52  *    btree
53  *
54  * When allocating some space with the sector allocator, the allocation comes
55  * with a reference to an open bucket - the caller is required to put that
56  * reference _after_ doing the index update that makes its allocation reachable.
57  */
58
59 static void bch2_open_bucket_hash_add(struct bch_fs *c, struct open_bucket *ob)
60 {
61         open_bucket_idx_t idx = ob - c->open_buckets;
62         open_bucket_idx_t *slot = open_bucket_hashslot(c, ob->dev, ob->bucket);
63
64         ob->hash = *slot;
65         *slot = idx;
66 }
67
68 static void bch2_open_bucket_hash_remove(struct bch_fs *c, struct open_bucket *ob)
69 {
70         open_bucket_idx_t idx = ob - c->open_buckets;
71         open_bucket_idx_t *slot = open_bucket_hashslot(c, ob->dev, ob->bucket);
72
73         while (*slot != idx) {
74                 BUG_ON(!*slot);
75                 slot = &c->open_buckets[*slot].hash;
76         }
77
78         *slot = ob->hash;
79         ob->hash = 0;
80 }
81
82 void __bch2_open_bucket_put(struct bch_fs *c, struct open_bucket *ob)
83 {
84         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
85
86         if (ob->ec) {
87                 bch2_ec_bucket_written(c, ob);
88                 return;
89         }
90
91         percpu_down_read(&c->mark_lock);
92         spin_lock(&ob->lock);
93
94         ob->valid = false;
95         ob->data_type = 0;
96
97         spin_unlock(&ob->lock);
98         percpu_up_read(&c->mark_lock);
99
100         spin_lock(&c->freelist_lock);
101         bch2_open_bucket_hash_remove(c, ob);
102
103         ob->freelist = c->open_buckets_freelist;
104         c->open_buckets_freelist = ob - c->open_buckets;
105
106         c->open_buckets_nr_free++;
107         ca->nr_open_buckets--;
108         spin_unlock(&c->freelist_lock);
109
110         closure_wake_up(&c->open_buckets_wait);
111 }
112
113 void bch2_open_bucket_write_error(struct bch_fs *c,
114                                   struct open_buckets *obs,
115                                   unsigned dev)
116 {
117         struct open_bucket *ob;
118         unsigned i;
119
120         open_bucket_for_each(c, obs, ob, i)
121                 if (ob->dev == dev && ob->ec)
122                         bch2_ec_bucket_cancel(c, ob);
123 }
124
125 static struct open_bucket *bch2_open_bucket_alloc(struct bch_fs *c)
126 {
127         struct open_bucket *ob;
128
129         BUG_ON(!c->open_buckets_freelist || !c->open_buckets_nr_free);
130
131         ob = c->open_buckets + c->open_buckets_freelist;
132         c->open_buckets_freelist = ob->freelist;
133         atomic_set(&ob->pin, 1);
134         ob->data_type = 0;
135
136         c->open_buckets_nr_free--;
137         return ob;
138 }
139
140 static void open_bucket_free_unused(struct bch_fs *c,
141                                     struct write_point *wp,
142                                     struct open_bucket *ob)
143 {
144         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
145         bool may_realloc = wp->data_type == BCH_DATA_user;
146
147         BUG_ON(ca->open_buckets_partial_nr >
148                ARRAY_SIZE(ca->open_buckets_partial));
149
150         if (ca->open_buckets_partial_nr <
151             ARRAY_SIZE(ca->open_buckets_partial) &&
152             may_realloc) {
153                 spin_lock(&c->freelist_lock);
154                 ob->on_partial_list = true;
155                 ca->open_buckets_partial[ca->open_buckets_partial_nr++] =
156                         ob - c->open_buckets;
157                 spin_unlock(&c->freelist_lock);
158
159                 closure_wake_up(&c->open_buckets_wait);
160                 closure_wake_up(&c->freelist_wait);
161         } else {
162                 bch2_open_bucket_put(c, ob);
163         }
164 }
165
166 /* _only_ for allocating the journal on a new device: */
167 long bch2_bucket_alloc_new_fs(struct bch_dev *ca)
168 {
169         while (ca->new_fs_bucket_idx < ca->mi.nbuckets) {
170                 u64 b = ca->new_fs_bucket_idx++;
171
172                 if (!is_superblock_bucket(ca, b) &&
173                     (!ca->buckets_nouse || !test_bit(b, ca->buckets_nouse)))
174                         return b;
175         }
176
177         return -1;
178 }
179
180 static inline unsigned open_buckets_reserved(enum alloc_reserve reserve)
181 {
182         switch (reserve) {
183         case RESERVE_btree:
184         case RESERVE_btree_movinggc:
185                 return 0;
186         case RESERVE_movinggc:
187                 return OPEN_BUCKETS_COUNT / 4;
188         default:
189                 return OPEN_BUCKETS_COUNT / 2;
190         }
191 }
192
193 static struct open_bucket *__try_alloc_bucket(struct bch_fs *c, struct bch_dev *ca,
194                                               u64 bucket,
195                                               enum alloc_reserve reserve,
196                                               struct bch_alloc_v4 *a,
197                                               u64 *skipped_open,
198                                               u64 *skipped_need_journal_commit,
199                                               u64 *skipped_nouse,
200                                               struct closure *cl)
201 {
202         struct open_bucket *ob;
203
204         if (unlikely(ca->buckets_nouse && test_bit(bucket, ca->buckets_nouse))) {
205                 (*skipped_nouse)++;
206                 return NULL;
207         }
208
209         if (bch2_bucket_is_open(c, ca->dev_idx, bucket)) {
210                 (*skipped_open)++;
211                 return NULL;
212         }
213
214         if (bch2_bucket_needs_journal_commit(&c->buckets_waiting_for_journal,
215                         c->journal.flushed_seq_ondisk, ca->dev_idx, bucket)) {
216                 (*skipped_need_journal_commit)++;
217                 return NULL;
218         }
219
220         spin_lock(&c->freelist_lock);
221
222         if (unlikely(c->open_buckets_nr_free <= open_buckets_reserved(reserve))) {
223                 if (cl)
224                         closure_wait(&c->open_buckets_wait, cl);
225
226                 if (!c->blocked_allocate_open_bucket)
227                         c->blocked_allocate_open_bucket = local_clock();
228
229                 spin_unlock(&c->freelist_lock);
230                 return ERR_PTR(-BCH_ERR_open_buckets_empty);
231         }
232
233         /* Recheck under lock: */
234         if (bch2_bucket_is_open(c, ca->dev_idx, bucket)) {
235                 spin_unlock(&c->freelist_lock);
236                 (*skipped_open)++;
237                 return NULL;
238         }
239
240         ob = bch2_open_bucket_alloc(c);
241
242         spin_lock(&ob->lock);
243
244         ob->valid       = true;
245         ob->sectors_free = ca->mi.bucket_size;
246         ob->alloc_reserve = reserve;
247         ob->dev         = ca->dev_idx;
248         ob->gen         = a->gen;
249         ob->bucket      = bucket;
250         spin_unlock(&ob->lock);
251
252         ca->nr_open_buckets++;
253         bch2_open_bucket_hash_add(c, ob);
254
255         if (c->blocked_allocate_open_bucket) {
256                 bch2_time_stats_update(
257                         &c->times[BCH_TIME_blocked_allocate_open_bucket],
258                         c->blocked_allocate_open_bucket);
259                 c->blocked_allocate_open_bucket = 0;
260         }
261
262         if (c->blocked_allocate) {
263                 bch2_time_stats_update(
264                         &c->times[BCH_TIME_blocked_allocate],
265                         c->blocked_allocate);
266                 c->blocked_allocate = 0;
267         }
268
269         spin_unlock(&c->freelist_lock);
270
271         trace_bucket_alloc(ca, bch2_alloc_reserves[reserve]);
272         return ob;
273 }
274
275 static struct open_bucket *try_alloc_bucket(struct btree_trans *trans, struct bch_dev *ca,
276                                             enum alloc_reserve reserve, u64 free_entry,
277                                             u64 *skipped_open,
278                                             u64 *skipped_need_journal_commit,
279                                             u64 *skipped_nouse,
280                                             struct bkey_s_c freespace_k,
281                                             struct closure *cl)
282 {
283         struct bch_fs *c = trans->c;
284         struct btree_iter iter = { NULL };
285         struct bkey_s_c k;
286         struct open_bucket *ob;
287         struct bch_alloc_v4 a;
288         u64 b = free_entry & ~(~0ULL << 56);
289         unsigned genbits = free_entry >> 56;
290         struct printbuf buf = PRINTBUF;
291         int ret;
292
293         if (b < ca->mi.first_bucket || b >= ca->mi.nbuckets) {
294                 prt_printf(&buf, "freespace btree has bucket outside allowed range %u-%llu\n"
295                        "  freespace key ",
296                         ca->mi.first_bucket, ca->mi.nbuckets);
297                 bch2_bkey_val_to_text(&buf, c, freespace_k);
298                 bch2_trans_inconsistent(trans, "%s", buf.buf);
299                 ob = ERR_PTR(-EIO);
300                 goto err;
301         }
302
303         bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc, POS(ca->dev_idx, b), BTREE_ITER_CACHED);
304         k = bch2_btree_iter_peek_slot(&iter);
305         ret = bkey_err(k);
306         if (ret) {
307                 ob = ERR_PTR(ret);
308                 goto err;
309         }
310
311         bch2_alloc_to_v4(k, &a);
312
313         if (genbits != (alloc_freespace_genbits(a) >> 56)) {
314                 prt_printf(&buf, "bucket in freespace btree with wrong genbits (got %u should be %llu)\n"
315                        "  freespace key ",
316                        genbits, alloc_freespace_genbits(a) >> 56);
317                 bch2_bkey_val_to_text(&buf, c, freespace_k);
318                 prt_printf(&buf, "\n  ");
319                 bch2_bkey_val_to_text(&buf, c, k);
320                 bch2_trans_inconsistent(trans, "%s", buf.buf);
321                 ob = ERR_PTR(-EIO);
322                 goto err;
323
324         }
325
326         if (a.data_type != BCH_DATA_free) {
327                 prt_printf(&buf, "non free bucket in freespace btree\n"
328                        "  freespace key ");
329                 bch2_bkey_val_to_text(&buf, c, freespace_k);
330                 prt_printf(&buf, "\n  ");
331                 bch2_bkey_val_to_text(&buf, c, k);
332                 bch2_trans_inconsistent(trans, "%s", buf.buf);
333                 ob = ERR_PTR(-EIO);
334                 goto err;
335         }
336
337         ob = __try_alloc_bucket(c, ca, b, reserve, &a,
338                                 skipped_open,
339                                 skipped_need_journal_commit,
340                                 skipped_nouse,
341                                 cl);
342         if (!ob)
343                 iter.path->preserve = false;
344 err:
345         set_btree_iter_dontneed(&iter);
346         bch2_trans_iter_exit(trans, &iter);
347         printbuf_exit(&buf);
348         return ob;
349 }
350
351 static struct open_bucket *try_alloc_partial_bucket(struct bch_fs *c, struct bch_dev *ca,
352                                                     enum alloc_reserve reserve)
353 {
354         struct open_bucket *ob;
355         int i;
356
357         spin_lock(&c->freelist_lock);
358
359         for (i = ca->open_buckets_partial_nr - 1; i >= 0; --i) {
360                 ob = c->open_buckets + ca->open_buckets_partial[i];
361
362                 if (reserve <= ob->alloc_reserve) {
363                         array_remove_item(ca->open_buckets_partial,
364                                           ca->open_buckets_partial_nr,
365                                           i);
366                         ob->on_partial_list = false;
367                         ob->alloc_reserve = reserve;
368                         spin_unlock(&c->freelist_lock);
369                         return ob;
370                 }
371         }
372
373         spin_unlock(&c->freelist_lock);
374         return NULL;
375 }
376
377 /*
378  * This path is for before the freespace btree is initialized:
379  *
380  * If ca->new_fs_bucket_idx is nonzero, we haven't yet marked superblock &
381  * journal buckets - journal buckets will be < ca->new_fs_bucket_idx
382  */
383 static noinline struct open_bucket *
384 bch2_bucket_alloc_early(struct btree_trans *trans,
385                         struct bch_dev *ca,
386                         enum alloc_reserve reserve,
387                         u64 *cur_bucket,
388                         u64 *buckets_seen,
389                         u64 *skipped_open,
390                         u64 *skipped_need_journal_commit,
391                         u64 *skipped_nouse,
392                         struct closure *cl)
393 {
394         struct btree_iter iter;
395         struct bkey_s_c k;
396         struct open_bucket *ob = NULL;
397         int ret;
398
399         *cur_bucket = max_t(u64, *cur_bucket, ca->mi.first_bucket);
400         *cur_bucket = max_t(u64, *cur_bucket, ca->new_fs_bucket_idx);
401
402         for_each_btree_key_norestart(trans, iter, BTREE_ID_alloc, POS(ca->dev_idx, *cur_bucket),
403                            BTREE_ITER_SLOTS, k, ret) {
404                 struct bch_alloc_v4 a;
405
406                 if (bkey_cmp(k.k->p, POS(ca->dev_idx, ca->mi.nbuckets)) >= 0)
407                         break;
408
409                 if (ca->new_fs_bucket_idx &&
410                     is_superblock_bucket(ca, k.k->p.offset))
411                         continue;
412
413                 bch2_alloc_to_v4(k, &a);
414
415                 if (a.data_type != BCH_DATA_free)
416                         continue;
417
418                 (*buckets_seen)++;
419
420                 ob = __try_alloc_bucket(trans->c, ca, k.k->p.offset, reserve, &a,
421                                         skipped_open,
422                                         skipped_need_journal_commit,
423                                         skipped_nouse,
424                                         cl);
425                 if (ob)
426                         break;
427         }
428         bch2_trans_iter_exit(trans, &iter);
429
430         *cur_bucket = iter.pos.offset;
431
432         return ob ?: ERR_PTR(ret ?: -BCH_ERR_no_buckets_found);
433 }
434
435 static struct open_bucket *bch2_bucket_alloc_freelist(struct btree_trans *trans,
436                                                    struct bch_dev *ca,
437                                                    enum alloc_reserve reserve,
438                                                    u64 *cur_bucket,
439                                                    u64 *buckets_seen,
440                                                    u64 *skipped_open,
441                                                    u64 *skipped_need_journal_commit,
442                                                    u64 *skipped_nouse,
443                                                    struct closure *cl)
444 {
445         struct btree_iter iter;
446         struct bkey_s_c k;
447         struct open_bucket *ob = NULL;
448         int ret;
449
450         BUG_ON(ca->new_fs_bucket_idx);
451
452         /*
453          * XXX:
454          * On transaction restart, we'd like to restart from the bucket we were
455          * at previously
456          */
457         for_each_btree_key_norestart(trans, iter, BTREE_ID_freespace,
458                                      POS(ca->dev_idx, *cur_bucket), 0, k, ret) {
459                 if (k.k->p.inode != ca->dev_idx)
460                         break;
461
462                 for (*cur_bucket = max(*cur_bucket, bkey_start_offset(k.k));
463                      *cur_bucket < k.k->p.offset;
464                      (*cur_bucket)++) {
465                         ret = btree_trans_too_many_iters(trans);
466                         if (ret)
467                                 break;
468
469                         (*buckets_seen)++;
470
471                         ob = try_alloc_bucket(trans, ca, reserve,
472                                               *cur_bucket,
473                                               skipped_open,
474                                               skipped_need_journal_commit,
475                                               skipped_nouse,
476                                               k, cl);
477                         if (ob)
478                                 break;
479                 }
480
481                 if (ob || ret)
482                         break;
483         }
484         bch2_trans_iter_exit(trans, &iter);
485
486         return ob ?: ERR_PTR(ret);
487 }
488
489 /**
490  * bch_bucket_alloc - allocate a single bucket from a specific device
491  *
492  * Returns index of bucket on success, 0 on failure
493  * */
494 static struct open_bucket *bch2_bucket_alloc_trans(struct btree_trans *trans,
495                                       struct bch_dev *ca,
496                                       enum alloc_reserve reserve,
497                                       bool may_alloc_partial,
498                                       struct closure *cl)
499 {
500         struct bch_fs *c = trans->c;
501         struct open_bucket *ob = NULL;
502         struct bch_dev_usage usage;
503         bool freespace_initialized = READ_ONCE(ca->mi.freespace_initialized);
504         u64 start = freespace_initialized ? 0 : ca->bucket_alloc_trans_early_cursor;
505         u64 avail;
506         u64 cur_bucket = start;
507         u64 buckets_seen = 0;
508         u64 skipped_open = 0;
509         u64 skipped_need_journal_commit = 0;
510         u64 skipped_nouse = 0;
511         bool waiting = false;
512 again:
513         usage = bch2_dev_usage_read(ca);
514         avail = dev_buckets_free(ca, usage, reserve);
515
516         if (usage.d[BCH_DATA_need_discard].buckets > avail)
517                 bch2_do_discards(c);
518
519         if (usage.d[BCH_DATA_need_gc_gens].buckets > avail)
520                 bch2_do_gc_gens(c);
521
522         if (should_invalidate_buckets(ca, usage))
523                 bch2_do_invalidates(c);
524
525         if (!avail) {
526                 if (cl && !waiting) {
527                         closure_wait(&c->freelist_wait, cl);
528                         waiting = true;
529                         goto again;
530                 }
531
532                 if (!c->blocked_allocate)
533                         c->blocked_allocate = local_clock();
534
535                 ob = ERR_PTR(-BCH_ERR_freelist_empty);
536                 goto err;
537         }
538
539         if (waiting)
540                 closure_wake_up(&c->freelist_wait);
541
542         if (may_alloc_partial) {
543                 ob = try_alloc_partial_bucket(c, ca, reserve);
544                 if (ob)
545                         return ob;
546         }
547
548         ob = likely(ca->mi.freespace_initialized)
549                 ? bch2_bucket_alloc_freelist(trans, ca, reserve,
550                                         &cur_bucket,
551                                         &buckets_seen,
552                                         &skipped_open,
553                                         &skipped_need_journal_commit,
554                                         &skipped_nouse,
555                                         cl)
556                 : bch2_bucket_alloc_early(trans, ca, reserve,
557                                         &cur_bucket,
558                                         &buckets_seen,
559                                         &skipped_open,
560                                         &skipped_need_journal_commit,
561                                         &skipped_nouse,
562                                         cl);
563
564         if (skipped_need_journal_commit * 2 > avail)
565                 bch2_journal_flush_async(&c->journal, NULL);
566
567         if (!ob && !freespace_initialized && start) {
568                 start = cur_bucket = 0;
569                 goto again;
570         }
571
572         if (!freespace_initialized)
573                 ca->bucket_alloc_trans_early_cursor = cur_bucket;
574 err:
575         if (!ob)
576                 ob = ERR_PTR(-BCH_ERR_no_buckets_found);
577
578         if (IS_ERR(ob)) {
579                 trace_bucket_alloc_fail(ca, bch2_alloc_reserves[reserve],
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                                         buckets_seen,
585                                         skipped_open,
586                                         skipped_need_journal_commit,
587                                         skipped_nouse,
588                                         cl == NULL,
589                                         bch2_err_str(PTR_ERR(ob)));
590                 atomic_long_inc(&c->bucket_alloc_fail);
591         }
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 open_bucket *ob;
602
603         bch2_trans_do(c, NULL, NULL, 0,
604                       PTR_ERR_OR_ZERO(ob = bch2_bucket_alloc_trans(&trans, ca, reserve,
605                                                                    may_alloc_partial, cl)));
606         return ob;
607 }
608
609 static int __dev_stripe_cmp(struct dev_stripe_state *stripe,
610                             unsigned l, unsigned r)
611 {
612         return ((stripe->next_alloc[l] > stripe->next_alloc[r]) -
613                 (stripe->next_alloc[l] < stripe->next_alloc[r]));
614 }
615
616 #define dev_stripe_cmp(l, r) __dev_stripe_cmp(stripe, l, r)
617
618 struct dev_alloc_list bch2_dev_alloc_list(struct bch_fs *c,
619                                           struct dev_stripe_state *stripe,
620                                           struct bch_devs_mask *devs)
621 {
622         struct dev_alloc_list ret = { .nr = 0 };
623         unsigned i;
624
625         for_each_set_bit(i, devs->d, BCH_SB_MEMBERS_MAX)
626                 ret.devs[ret.nr++] = i;
627
628         bubble_sort(ret.devs, ret.nr, dev_stripe_cmp);
629         return ret;
630 }
631
632 void bch2_dev_stripe_increment(struct bch_dev *ca,
633                                struct dev_stripe_state *stripe)
634 {
635         u64 *v = stripe->next_alloc + ca->dev_idx;
636         u64 free_space = dev_buckets_available(ca, RESERVE_none);
637         u64 free_space_inv = free_space
638                 ? div64_u64(1ULL << 48, free_space)
639                 : 1ULL << 48;
640         u64 scale = *v / 4;
641
642         if (*v + free_space_inv >= *v)
643                 *v += free_space_inv;
644         else
645                 *v = U64_MAX;
646
647         for (v = stripe->next_alloc;
648              v < stripe->next_alloc + ARRAY_SIZE(stripe->next_alloc); v++)
649                 *v = *v < scale ? 0 : *v - scale;
650 }
651
652 #define BUCKET_MAY_ALLOC_PARTIAL        (1 << 0)
653 #define BUCKET_ALLOC_USE_DURABILITY     (1 << 1)
654
655 static void add_new_bucket(struct bch_fs *c,
656                            struct open_buckets *ptrs,
657                            struct bch_devs_mask *devs_may_alloc,
658                            unsigned *nr_effective,
659                            bool *have_cache,
660                            unsigned flags,
661                            struct open_bucket *ob)
662 {
663         unsigned durability =
664                 bch_dev_bkey_exists(c, ob->dev)->mi.durability;
665
666         __clear_bit(ob->dev, devs_may_alloc->d);
667         *nr_effective   += (flags & BUCKET_ALLOC_USE_DURABILITY)
668                 ? durability : 1;
669         *have_cache     |= !durability;
670
671         ob_push(c, ptrs, ob);
672 }
673
674 static int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
675                       struct open_buckets *ptrs,
676                       struct dev_stripe_state *stripe,
677                       struct bch_devs_mask *devs_may_alloc,
678                       unsigned nr_replicas,
679                       unsigned *nr_effective,
680                       bool *have_cache,
681                       enum alloc_reserve reserve,
682                       unsigned flags,
683                       struct closure *cl)
684 {
685         struct bch_fs *c = trans->c;
686         struct dev_alloc_list devs_sorted =
687                 bch2_dev_alloc_list(c, stripe, devs_may_alloc);
688         unsigned dev;
689         struct bch_dev *ca;
690         int ret = 0;
691         unsigned i;
692
693         BUG_ON(*nr_effective >= nr_replicas);
694
695         for (i = 0; i < devs_sorted.nr; i++) {
696                 struct open_bucket *ob;
697
698                 dev = devs_sorted.devs[i];
699
700                 rcu_read_lock();
701                 ca = rcu_dereference(c->devs[dev]);
702                 if (ca)
703                         percpu_ref_get(&ca->ref);
704                 rcu_read_unlock();
705
706                 if (!ca)
707                         continue;
708
709                 if (!ca->mi.durability && *have_cache) {
710                         percpu_ref_put(&ca->ref);
711                         continue;
712                 }
713
714                 ob = bch2_bucket_alloc_trans(trans, ca, reserve,
715                                 flags & BUCKET_MAY_ALLOC_PARTIAL, cl);
716                 if (!IS_ERR(ob))
717                         bch2_dev_stripe_increment(ca, stripe);
718                 percpu_ref_put(&ca->ref);
719
720                 ret = PTR_ERR_OR_ZERO(ob);
721                 if (ret) {
722                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart) || cl)
723                                 break;
724                         continue;
725                 }
726
727                 add_new_bucket(c, ptrs, devs_may_alloc,
728                                nr_effective, have_cache, flags, ob);
729
730                 if (*nr_effective >= nr_replicas)
731                         break;
732         }
733
734         if (*nr_effective >= nr_replicas)
735                 ret = 0;
736         else if (!ret)
737                 ret = -BCH_ERR_insufficient_devices;
738
739         return ret;
740 }
741
742 int bch2_bucket_alloc_set(struct bch_fs *c,
743                       struct open_buckets *ptrs,
744                       struct dev_stripe_state *stripe,
745                       struct bch_devs_mask *devs_may_alloc,
746                       unsigned nr_replicas,
747                       unsigned *nr_effective,
748                       bool *have_cache,
749                       enum alloc_reserve reserve,
750                       unsigned flags,
751                       struct closure *cl)
752 {
753         return bch2_trans_do(c, NULL, NULL, 0,
754                       bch2_bucket_alloc_set_trans(&trans, ptrs, stripe,
755                                               devs_may_alloc, nr_replicas,
756                                               nr_effective, have_cache, reserve,
757                                               flags, cl));
758 }
759
760 /* Allocate from stripes: */
761
762 /*
763  * if we can't allocate a new stripe because there are already too many
764  * partially filled stripes, force allocating from an existing stripe even when
765  * it's to a device we don't want:
766  */
767
768 static int bucket_alloc_from_stripe(struct bch_fs *c,
769                          struct open_buckets *ptrs,
770                          struct write_point *wp,
771                          struct bch_devs_mask *devs_may_alloc,
772                          u16 target,
773                          unsigned erasure_code,
774                          unsigned nr_replicas,
775                          unsigned *nr_effective,
776                          bool *have_cache,
777                          unsigned flags,
778                          struct closure *cl)
779 {
780         struct dev_alloc_list devs_sorted;
781         struct ec_stripe_head *h;
782         struct open_bucket *ob;
783         struct bch_dev *ca;
784         unsigned i, ec_idx;
785
786         if (!erasure_code)
787                 return 0;
788
789         if (nr_replicas < 2)
790                 return 0;
791
792         if (ec_open_bucket(c, ptrs))
793                 return 0;
794
795         h = bch2_ec_stripe_head_get(c, target, 0, nr_replicas - 1,
796                                     wp == &c->copygc_write_point,
797                                     cl);
798         if (IS_ERR(h))
799                 return -PTR_ERR(h);
800         if (!h)
801                 return 0;
802
803         devs_sorted = bch2_dev_alloc_list(c, &wp->stripe, devs_may_alloc);
804
805         for (i = 0; i < devs_sorted.nr; i++)
806                 for (ec_idx = 0; ec_idx < h->s->nr_data; ec_idx++) {
807                         if (!h->s->blocks[ec_idx])
808                                 continue;
809
810                         ob = c->open_buckets + h->s->blocks[ec_idx];
811                         if (ob->dev == devs_sorted.devs[i] &&
812                             !test_and_set_bit(ec_idx, h->s->blocks_allocated))
813                                 goto got_bucket;
814                 }
815         goto out_put_head;
816 got_bucket:
817         ca = bch_dev_bkey_exists(c, ob->dev);
818
819         ob->ec_idx      = ec_idx;
820         ob->ec          = h->s;
821
822         add_new_bucket(c, ptrs, devs_may_alloc,
823                        nr_effective, have_cache, flags, ob);
824         atomic_inc(&h->s->pin);
825 out_put_head:
826         bch2_ec_stripe_head_put(c, h);
827         return 0;
828 }
829
830 /* Sector allocator */
831
832 static void get_buckets_from_writepoint(struct bch_fs *c,
833                                         struct open_buckets *ptrs,
834                                         struct write_point *wp,
835                                         struct bch_devs_mask *devs_may_alloc,
836                                         unsigned nr_replicas,
837                                         unsigned *nr_effective,
838                                         bool *have_cache,
839                                         unsigned flags,
840                                         bool need_ec)
841 {
842         struct open_buckets ptrs_skip = { .nr = 0 };
843         struct open_bucket *ob;
844         unsigned i;
845
846         open_bucket_for_each(c, &wp->ptrs, ob, i) {
847                 struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
848
849                 if (*nr_effective < nr_replicas &&
850                     test_bit(ob->dev, devs_may_alloc->d) &&
851                     (ca->mi.durability ||
852                      (wp->data_type == BCH_DATA_user && !*have_cache)) &&
853                     (ob->ec || !need_ec)) {
854                         add_new_bucket(c, ptrs, devs_may_alloc,
855                                        nr_effective, have_cache,
856                                        flags, ob);
857                 } else {
858                         ob_push(c, &ptrs_skip, ob);
859                 }
860         }
861         wp->ptrs = ptrs_skip;
862 }
863
864 static int open_bucket_add_buckets(struct btree_trans *trans,
865                         struct open_buckets *ptrs,
866                         struct write_point *wp,
867                         struct bch_devs_list *devs_have,
868                         u16 target,
869                         unsigned erasure_code,
870                         unsigned nr_replicas,
871                         unsigned *nr_effective,
872                         bool *have_cache,
873                         enum alloc_reserve reserve,
874                         unsigned flags,
875                         struct closure *_cl)
876 {
877         struct bch_fs *c = trans->c;
878         struct bch_devs_mask devs;
879         struct open_bucket *ob;
880         struct closure *cl = NULL;
881         int ret;
882         unsigned i;
883
884         rcu_read_lock();
885         devs = target_rw_devs(c, wp->data_type, target);
886         rcu_read_unlock();
887
888         /* Don't allocate from devices we already have pointers to: */
889         for (i = 0; i < devs_have->nr; i++)
890                 __clear_bit(devs_have->devs[i], devs.d);
891
892         open_bucket_for_each(c, ptrs, ob, i)
893                 __clear_bit(ob->dev, devs.d);
894
895         if (erasure_code) {
896                 if (!ec_open_bucket(c, ptrs)) {
897                         get_buckets_from_writepoint(c, ptrs, wp, &devs,
898                                                     nr_replicas, nr_effective,
899                                                     have_cache, flags, true);
900                         if (*nr_effective >= nr_replicas)
901                                 return 0;
902                 }
903
904                 if (!ec_open_bucket(c, ptrs)) {
905                         ret = bucket_alloc_from_stripe(c, ptrs, wp, &devs,
906                                                  target, erasure_code,
907                                                  nr_replicas, nr_effective,
908                                                  have_cache, flags, _cl);
909                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||
910                             bch2_err_matches(ret, BCH_ERR_freelist_empty) ||
911                             bch2_err_matches(ret, BCH_ERR_open_buckets_empty))
912                                 return ret;
913                         if (*nr_effective >= nr_replicas)
914                                 return 0;
915                 }
916         }
917
918         get_buckets_from_writepoint(c, ptrs, wp, &devs,
919                                     nr_replicas, nr_effective,
920                                     have_cache, flags, false);
921         if (*nr_effective >= nr_replicas)
922                 return 0;
923
924 retry_blocking:
925         /*
926          * Try nonblocking first, so that if one device is full we'll try from
927          * other devices:
928          */
929         ret = bch2_bucket_alloc_set_trans(trans, ptrs, &wp->stripe, &devs,
930                                 nr_replicas, nr_effective, have_cache,
931                                 reserve, flags, cl);
932         if (ret &&
933             !bch2_err_matches(ret, BCH_ERR_transaction_restart) &&
934             !bch2_err_matches(ret, BCH_ERR_insufficient_devices) &&
935             !cl && _cl) {
936                 cl = _cl;
937                 goto retry_blocking;
938         }
939
940         return ret;
941 }
942
943 void bch2_open_buckets_stop_dev(struct bch_fs *c, struct bch_dev *ca,
944                                 struct open_buckets *obs)
945 {
946         struct open_buckets ptrs = { .nr = 0 };
947         struct open_bucket *ob, *ob2;
948         unsigned i, j;
949
950         open_bucket_for_each(c, obs, ob, i) {
951                 bool drop = !ca || ob->dev == ca->dev_idx;
952
953                 if (!drop && ob->ec) {
954                         mutex_lock(&ob->ec->lock);
955                         for (j = 0; j < ob->ec->new_stripe.key.v.nr_blocks; j++) {
956                                 if (!ob->ec->blocks[j])
957                                         continue;
958
959                                 ob2 = c->open_buckets + ob->ec->blocks[j];
960                                 drop |= ob2->dev == ca->dev_idx;
961                         }
962                         mutex_unlock(&ob->ec->lock);
963                 }
964
965                 if (drop)
966                         bch2_open_bucket_put(c, ob);
967                 else
968                         ob_push(c, &ptrs, ob);
969         }
970
971         *obs = ptrs;
972 }
973
974 void bch2_writepoint_stop(struct bch_fs *c, struct bch_dev *ca,
975                           struct write_point *wp)
976 {
977         mutex_lock(&wp->lock);
978         bch2_open_buckets_stop_dev(c, ca, &wp->ptrs);
979         mutex_unlock(&wp->lock);
980 }
981
982 static inline struct hlist_head *writepoint_hash(struct bch_fs *c,
983                                                  unsigned long write_point)
984 {
985         unsigned hash =
986                 hash_long(write_point, ilog2(ARRAY_SIZE(c->write_points_hash)));
987
988         return &c->write_points_hash[hash];
989 }
990
991 static struct write_point *__writepoint_find(struct hlist_head *head,
992                                              unsigned long write_point)
993 {
994         struct write_point *wp;
995
996         rcu_read_lock();
997         hlist_for_each_entry_rcu(wp, head, node)
998                 if (wp->write_point == write_point)
999                         goto out;
1000         wp = NULL;
1001 out:
1002         rcu_read_unlock();
1003         return wp;
1004 }
1005
1006 static inline bool too_many_writepoints(struct bch_fs *c, unsigned factor)
1007 {
1008         u64 stranded    = c->write_points_nr * c->bucket_size_max;
1009         u64 free        = bch2_fs_usage_read_short(c).free;
1010
1011         return stranded * factor > free;
1012 }
1013
1014 static bool try_increase_writepoints(struct bch_fs *c)
1015 {
1016         struct write_point *wp;
1017
1018         if (c->write_points_nr == ARRAY_SIZE(c->write_points) ||
1019             too_many_writepoints(c, 32))
1020                 return false;
1021
1022         wp = c->write_points + c->write_points_nr++;
1023         hlist_add_head_rcu(&wp->node, writepoint_hash(c, wp->write_point));
1024         return true;
1025 }
1026
1027 static bool try_decrease_writepoints(struct bch_fs *c,
1028                                      unsigned old_nr)
1029 {
1030         struct write_point *wp;
1031
1032         mutex_lock(&c->write_points_hash_lock);
1033         if (c->write_points_nr < old_nr) {
1034                 mutex_unlock(&c->write_points_hash_lock);
1035                 return true;
1036         }
1037
1038         if (c->write_points_nr == 1 ||
1039             !too_many_writepoints(c, 8)) {
1040                 mutex_unlock(&c->write_points_hash_lock);
1041                 return false;
1042         }
1043
1044         wp = c->write_points + --c->write_points_nr;
1045
1046         hlist_del_rcu(&wp->node);
1047         mutex_unlock(&c->write_points_hash_lock);
1048
1049         bch2_writepoint_stop(c, NULL, wp);
1050         return true;
1051 }
1052
1053 static void bch2_trans_mutex_lock(struct btree_trans *trans,
1054                                   struct mutex *lock)
1055 {
1056         if (!mutex_trylock(lock)) {
1057                 bch2_trans_unlock(trans);
1058                 mutex_lock(lock);
1059         }
1060 }
1061
1062 static struct write_point *writepoint_find(struct btree_trans *trans,
1063                                            unsigned long write_point)
1064 {
1065         struct bch_fs *c = trans->c;
1066         struct write_point *wp, *oldest;
1067         struct hlist_head *head;
1068
1069         if (!(write_point & 1UL)) {
1070                 wp = (struct write_point *) write_point;
1071                 bch2_trans_mutex_lock(trans, &wp->lock);
1072                 return wp;
1073         }
1074
1075         head = writepoint_hash(c, write_point);
1076 restart_find:
1077         wp = __writepoint_find(head, write_point);
1078         if (wp) {
1079 lock_wp:
1080                 bch2_trans_mutex_lock(trans, &wp->lock);
1081                 if (wp->write_point == write_point)
1082                         goto out;
1083                 mutex_unlock(&wp->lock);
1084                 goto restart_find;
1085         }
1086 restart_find_oldest:
1087         oldest = NULL;
1088         for (wp = c->write_points;
1089              wp < c->write_points + c->write_points_nr; wp++)
1090                 if (!oldest || time_before64(wp->last_used, oldest->last_used))
1091                         oldest = wp;
1092
1093         bch2_trans_mutex_lock(trans, &oldest->lock);
1094         bch2_trans_mutex_lock(trans, &c->write_points_hash_lock);
1095         if (oldest >= c->write_points + c->write_points_nr ||
1096             try_increase_writepoints(c)) {
1097                 mutex_unlock(&c->write_points_hash_lock);
1098                 mutex_unlock(&oldest->lock);
1099                 goto restart_find_oldest;
1100         }
1101
1102         wp = __writepoint_find(head, write_point);
1103         if (wp && wp != oldest) {
1104                 mutex_unlock(&c->write_points_hash_lock);
1105                 mutex_unlock(&oldest->lock);
1106                 goto lock_wp;
1107         }
1108
1109         wp = oldest;
1110         hlist_del_rcu(&wp->node);
1111         wp->write_point = write_point;
1112         hlist_add_head_rcu(&wp->node, head);
1113         mutex_unlock(&c->write_points_hash_lock);
1114 out:
1115         wp->last_used = sched_clock();
1116         return wp;
1117 }
1118
1119 /*
1120  * Get us an open_bucket we can allocate from, return with it locked:
1121  */
1122 struct write_point *bch2_alloc_sectors_start_trans(struct btree_trans *trans,
1123                                 unsigned target,
1124                                 unsigned erasure_code,
1125                                 struct write_point_specifier write_point,
1126                                 struct bch_devs_list *devs_have,
1127                                 unsigned nr_replicas,
1128                                 unsigned nr_replicas_required,
1129                                 enum alloc_reserve reserve,
1130                                 unsigned flags,
1131                                 struct closure *cl)
1132 {
1133         struct bch_fs *c = trans->c;
1134         struct write_point *wp;
1135         struct open_bucket *ob;
1136         struct open_buckets ptrs;
1137         unsigned nr_effective, write_points_nr;
1138         unsigned ob_flags = 0;
1139         bool have_cache;
1140         int ret;
1141         int i;
1142
1143         if (!(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS))
1144                 ob_flags |= BUCKET_ALLOC_USE_DURABILITY;
1145
1146         BUG_ON(!nr_replicas || !nr_replicas_required);
1147 retry:
1148         ptrs.nr         = 0;
1149         nr_effective    = 0;
1150         write_points_nr = c->write_points_nr;
1151         have_cache      = false;
1152
1153         wp = writepoint_find(trans, write_point.v);
1154
1155         if (wp->data_type == BCH_DATA_user)
1156                 ob_flags |= BUCKET_MAY_ALLOC_PARTIAL;
1157
1158         /* metadata may not allocate on cache devices: */
1159         if (wp->data_type != BCH_DATA_user)
1160                 have_cache = true;
1161
1162         if (!target || (flags & BCH_WRITE_ONLY_SPECIFIED_DEVS)) {
1163                 ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
1164                                               target, erasure_code,
1165                                               nr_replicas, &nr_effective,
1166                                               &have_cache, reserve,
1167                                               ob_flags, cl);
1168         } else {
1169                 ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
1170                                               target, erasure_code,
1171                                               nr_replicas, &nr_effective,
1172                                               &have_cache, reserve,
1173                                               ob_flags, NULL);
1174                 if (!ret ||
1175                     bch2_err_matches(ret, BCH_ERR_transaction_restart))
1176                         goto alloc_done;
1177
1178                 ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
1179                                               0, erasure_code,
1180                                               nr_replicas, &nr_effective,
1181                                               &have_cache, reserve,
1182                                               ob_flags, cl);
1183         }
1184 alloc_done:
1185         BUG_ON(!ret && nr_effective < nr_replicas);
1186
1187         if (erasure_code && !ec_open_bucket(c, &ptrs))
1188                 pr_debug("failed to get ec bucket: ret %u", ret);
1189
1190         if (ret == -BCH_ERR_insufficient_devices &&
1191             nr_effective >= nr_replicas_required)
1192                 ret = 0;
1193
1194         if (ret)
1195                 goto err;
1196
1197         /* Free buckets we didn't use: */
1198         open_bucket_for_each(c, &wp->ptrs, ob, i)
1199                 open_bucket_free_unused(c, wp, ob);
1200
1201         wp->ptrs = ptrs;
1202
1203         wp->sectors_free = UINT_MAX;
1204
1205         open_bucket_for_each(c, &wp->ptrs, ob, i)
1206                 wp->sectors_free = min(wp->sectors_free, ob->sectors_free);
1207
1208         BUG_ON(!wp->sectors_free || wp->sectors_free == UINT_MAX);
1209
1210         return wp;
1211 err:
1212         open_bucket_for_each(c, &wp->ptrs, ob, i)
1213                 if (ptrs.nr < ARRAY_SIZE(ptrs.v))
1214                         ob_push(c, &ptrs, ob);
1215                 else
1216                         open_bucket_free_unused(c, wp, ob);
1217         wp->ptrs = ptrs;
1218
1219         mutex_unlock(&wp->lock);
1220
1221         if (bch2_err_matches(ret, BCH_ERR_freelist_empty) &&
1222             try_decrease_writepoints(c, write_points_nr))
1223                 goto retry;
1224
1225         if (bch2_err_matches(ret, BCH_ERR_open_buckets_empty) ||
1226             bch2_err_matches(ret, BCH_ERR_freelist_empty))
1227                 return cl ? ERR_PTR(-EAGAIN) : ERR_PTR(-ENOSPC);
1228
1229         if (bch2_err_matches(ret, BCH_ERR_insufficient_devices))
1230                 return ERR_PTR(-EROFS);
1231
1232         return ERR_PTR(ret);
1233 }
1234
1235 struct write_point *bch2_alloc_sectors_start(struct bch_fs *c,
1236                                 unsigned target,
1237                                 unsigned erasure_code,
1238                                 struct write_point_specifier write_point,
1239                                 struct bch_devs_list *devs_have,
1240                                 unsigned nr_replicas,
1241                                 unsigned nr_replicas_required,
1242                                 enum alloc_reserve reserve,
1243                                 unsigned flags,
1244                                 struct closure *cl)
1245 {
1246         struct write_point *wp;
1247
1248         bch2_trans_do(c, NULL, NULL, 0,
1249                       PTR_ERR_OR_ZERO(wp = bch2_alloc_sectors_start_trans(&trans, target,
1250                                                         erasure_code,
1251                                                         write_point,
1252                                                         devs_have,
1253                                                         nr_replicas,
1254                                                         nr_replicas_required,
1255                                                         reserve,
1256                                                         flags, cl)));
1257         return wp;
1258
1259 }
1260
1261 struct bch_extent_ptr bch2_ob_ptr(struct bch_fs *c, struct open_bucket *ob)
1262 {
1263         struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
1264
1265         return (struct bch_extent_ptr) {
1266                 .type   = 1 << BCH_EXTENT_ENTRY_ptr,
1267                 .gen    = ob->gen,
1268                 .dev    = ob->dev,
1269                 .offset = bucket_to_sector(ca, ob->bucket) +
1270                         ca->mi.bucket_size -
1271                         ob->sectors_free,
1272         };
1273 }
1274
1275 /*
1276  * Append pointers to the space we just allocated to @k, and mark @sectors space
1277  * as allocated out of @ob
1278  */
1279 void bch2_alloc_sectors_append_ptrs(struct bch_fs *c, struct write_point *wp,
1280                                     struct bkey_i *k, unsigned sectors,
1281                                     bool cached)
1282
1283 {
1284         struct open_bucket *ob;
1285         unsigned i;
1286
1287         BUG_ON(sectors > wp->sectors_free);
1288         wp->sectors_free -= sectors;
1289
1290         open_bucket_for_each(c, &wp->ptrs, ob, i) {
1291                 struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
1292                 struct bch_extent_ptr ptr = bch2_ob_ptr(c, ob);
1293
1294                 ptr.cached = cached ||
1295                         (!ca->mi.durability &&
1296                          wp->data_type == BCH_DATA_user);
1297
1298                 bch2_bkey_append_ptr(k, ptr);
1299
1300                 BUG_ON(sectors > ob->sectors_free);
1301                 ob->sectors_free -= sectors;
1302         }
1303 }
1304
1305 /*
1306  * Append pointers to the space we just allocated to @k, and mark @sectors space
1307  * as allocated out of @ob
1308  */
1309 void bch2_alloc_sectors_done(struct bch_fs *c, struct write_point *wp)
1310 {
1311         struct open_buckets ptrs = { .nr = 0 }, keep = { .nr = 0 };
1312         struct open_bucket *ob;
1313         unsigned i;
1314
1315         open_bucket_for_each(c, &wp->ptrs, ob, i)
1316                 ob_push(c, !ob->sectors_free ? &ptrs : &keep, ob);
1317         wp->ptrs = keep;
1318
1319         mutex_unlock(&wp->lock);
1320
1321         bch2_open_buckets_put(c, &ptrs);
1322 }
1323
1324 static inline void writepoint_init(struct write_point *wp,
1325                                    enum bch_data_type type)
1326 {
1327         mutex_init(&wp->lock);
1328         wp->data_type = type;
1329 }
1330
1331 void bch2_fs_allocator_foreground_init(struct bch_fs *c)
1332 {
1333         struct open_bucket *ob;
1334         struct write_point *wp;
1335
1336         mutex_init(&c->write_points_hash_lock);
1337         c->write_points_nr = ARRAY_SIZE(c->write_points);
1338
1339         /* open bucket 0 is a sentinal NULL: */
1340         spin_lock_init(&c->open_buckets[0].lock);
1341
1342         for (ob = c->open_buckets + 1;
1343              ob < c->open_buckets + ARRAY_SIZE(c->open_buckets); ob++) {
1344                 spin_lock_init(&ob->lock);
1345                 c->open_buckets_nr_free++;
1346
1347                 ob->freelist = c->open_buckets_freelist;
1348                 c->open_buckets_freelist = ob - c->open_buckets;
1349         }
1350
1351         writepoint_init(&c->btree_write_point,          BCH_DATA_btree);
1352         writepoint_init(&c->rebalance_write_point,      BCH_DATA_user);
1353         writepoint_init(&c->copygc_write_point,         BCH_DATA_user);
1354
1355         for (wp = c->write_points;
1356              wp < c->write_points + c->write_points_nr; wp++) {
1357                 writepoint_init(wp, BCH_DATA_user);
1358
1359                 wp->last_used   = sched_clock();
1360                 wp->write_point = (unsigned long) wp;
1361                 hlist_add_head_rcu(&wp->node,
1362                                    writepoint_hash(c, wp->write_point));
1363         }
1364 }
1365
1366 void bch2_open_buckets_to_text(struct printbuf *out, struct bch_fs *c)
1367 {
1368         struct open_bucket *ob;
1369
1370         for (ob = c->open_buckets;
1371              ob < c->open_buckets + ARRAY_SIZE(c->open_buckets);
1372              ob++) {
1373                 spin_lock(&ob->lock);
1374                 if (ob->valid && !ob->on_partial_list) {
1375                         prt_printf(out, "%zu ref %u type %s %u:%llu:%u\n",
1376                                ob - c->open_buckets,
1377                                atomic_read(&ob->pin),
1378                                bch2_data_types[ob->data_type],
1379                                ob->dev, ob->bucket, ob->gen);
1380                 }
1381                 spin_unlock(&ob->lock);
1382         }
1383 }