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Update bcachefs sources to 0939e1c732 fixup! bcachefs: Rework lru btree
[bcachefs-tools-debian] / libbcachefs / alloc_background.c
1 // SPDX-License-Identifier: GPL-2.0
2 #include "bcachefs.h"
3 #include "alloc_background.h"
4 #include "alloc_foreground.h"
5 #include "backpointers.h"
6 #include "btree_cache.h"
7 #include "btree_io.h"
8 #include "btree_key_cache.h"
9 #include "btree_update.h"
10 #include "btree_update_interior.h"
11 #include "btree_gc.h"
12 #include "buckets.h"
13 #include "buckets_waiting_for_journal.h"
14 #include "clock.h"
15 #include "debug.h"
16 #include "ec.h"
17 #include "error.h"
18 #include "lru.h"
19 #include "recovery.h"
20 #include "varint.h"
21
22 #include <linux/kthread.h>
23 #include <linux/math64.h>
24 #include <linux/random.h>
25 #include <linux/rculist.h>
26 #include <linux/rcupdate.h>
27 #include <linux/sched/task.h>
28 #include <linux/sort.h>
29 #include <trace/events/bcachefs.h>
30
31 /* Persistent alloc info: */
32
33 static const unsigned BCH_ALLOC_V1_FIELD_BYTES[] = {
34 #define x(name, bits) [BCH_ALLOC_FIELD_V1_##name] = bits / 8,
35         BCH_ALLOC_FIELDS_V1()
36 #undef x
37 };
38
39 struct bkey_alloc_unpacked {
40         u64             journal_seq;
41         u8              gen;
42         u8              oldest_gen;
43         u8              data_type;
44         bool            need_discard:1;
45         bool            need_inc_gen:1;
46 #define x(_name, _bits) u##_bits _name;
47         BCH_ALLOC_FIELDS_V2()
48 #undef  x
49 };
50
51 static inline u64 alloc_field_v1_get(const struct bch_alloc *a,
52                                      const void **p, unsigned field)
53 {
54         unsigned bytes = BCH_ALLOC_V1_FIELD_BYTES[field];
55         u64 v;
56
57         if (!(a->fields & (1 << field)))
58                 return 0;
59
60         switch (bytes) {
61         case 1:
62                 v = *((const u8 *) *p);
63                 break;
64         case 2:
65                 v = le16_to_cpup(*p);
66                 break;
67         case 4:
68                 v = le32_to_cpup(*p);
69                 break;
70         case 8:
71                 v = le64_to_cpup(*p);
72                 break;
73         default:
74                 BUG();
75         }
76
77         *p += bytes;
78         return v;
79 }
80
81 static inline void alloc_field_v1_put(struct bkey_i_alloc *a, void **p,
82                                       unsigned field, u64 v)
83 {
84         unsigned bytes = BCH_ALLOC_V1_FIELD_BYTES[field];
85
86         if (!v)
87                 return;
88
89         a->v.fields |= 1 << field;
90
91         switch (bytes) {
92         case 1:
93                 *((u8 *) *p) = v;
94                 break;
95         case 2:
96                 *((__le16 *) *p) = cpu_to_le16(v);
97                 break;
98         case 4:
99                 *((__le32 *) *p) = cpu_to_le32(v);
100                 break;
101         case 8:
102                 *((__le64 *) *p) = cpu_to_le64(v);
103                 break;
104         default:
105                 BUG();
106         }
107
108         *p += bytes;
109 }
110
111 static void bch2_alloc_unpack_v1(struct bkey_alloc_unpacked *out,
112                                  struct bkey_s_c k)
113 {
114         const struct bch_alloc *in = bkey_s_c_to_alloc(k).v;
115         const void *d = in->data;
116         unsigned idx = 0;
117
118         out->gen = in->gen;
119
120 #define x(_name, _bits) out->_name = alloc_field_v1_get(in, &d, idx++);
121         BCH_ALLOC_FIELDS_V1()
122 #undef  x
123 }
124
125 static int bch2_alloc_unpack_v2(struct bkey_alloc_unpacked *out,
126                                 struct bkey_s_c k)
127 {
128         struct bkey_s_c_alloc_v2 a = bkey_s_c_to_alloc_v2(k);
129         const u8 *in = a.v->data;
130         const u8 *end = bkey_val_end(a);
131         unsigned fieldnr = 0;
132         int ret;
133         u64 v;
134
135         out->gen        = a.v->gen;
136         out->oldest_gen = a.v->oldest_gen;
137         out->data_type  = a.v->data_type;
138
139 #define x(_name, _bits)                                                 \
140         if (fieldnr < a.v->nr_fields) {                                 \
141                 ret = bch2_varint_decode_fast(in, end, &v);             \
142                 if (ret < 0)                                            \
143                         return ret;                                     \
144                 in += ret;                                              \
145         } else {                                                        \
146                 v = 0;                                                  \
147         }                                                               \
148         out->_name = v;                                                 \
149         if (v != out->_name)                                            \
150                 return -1;                                              \
151         fieldnr++;
152
153         BCH_ALLOC_FIELDS_V2()
154 #undef  x
155         return 0;
156 }
157
158 static int bch2_alloc_unpack_v3(struct bkey_alloc_unpacked *out,
159                                 struct bkey_s_c k)
160 {
161         struct bkey_s_c_alloc_v3 a = bkey_s_c_to_alloc_v3(k);
162         const u8 *in = a.v->data;
163         const u8 *end = bkey_val_end(a);
164         unsigned fieldnr = 0;
165         int ret;
166         u64 v;
167
168         out->gen        = a.v->gen;
169         out->oldest_gen = a.v->oldest_gen;
170         out->data_type  = a.v->data_type;
171         out->need_discard = BCH_ALLOC_V3_NEED_DISCARD(a.v);
172         out->need_inc_gen = BCH_ALLOC_V3_NEED_INC_GEN(a.v);
173         out->journal_seq = le64_to_cpu(a.v->journal_seq);
174
175 #define x(_name, _bits)                                                 \
176         if (fieldnr < a.v->nr_fields) {                                 \
177                 ret = bch2_varint_decode_fast(in, end, &v);             \
178                 if (ret < 0)                                            \
179                         return ret;                                     \
180                 in += ret;                                              \
181         } else {                                                        \
182                 v = 0;                                                  \
183         }                                                               \
184         out->_name = v;                                                 \
185         if (v != out->_name)                                            \
186                 return -1;                                              \
187         fieldnr++;
188
189         BCH_ALLOC_FIELDS_V2()
190 #undef  x
191         return 0;
192 }
193
194 static struct bkey_alloc_unpacked bch2_alloc_unpack(struct bkey_s_c k)
195 {
196         struct bkey_alloc_unpacked ret = { .gen = 0 };
197
198         switch (k.k->type) {
199         case KEY_TYPE_alloc:
200                 bch2_alloc_unpack_v1(&ret, k);
201                 break;
202         case KEY_TYPE_alloc_v2:
203                 bch2_alloc_unpack_v2(&ret, k);
204                 break;
205         case KEY_TYPE_alloc_v3:
206                 bch2_alloc_unpack_v3(&ret, k);
207                 break;
208         }
209
210         return ret;
211 }
212
213 static unsigned bch_alloc_v1_val_u64s(const struct bch_alloc *a)
214 {
215         unsigned i, bytes = offsetof(struct bch_alloc, data);
216
217         for (i = 0; i < ARRAY_SIZE(BCH_ALLOC_V1_FIELD_BYTES); i++)
218                 if (a->fields & (1 << i))
219                         bytes += BCH_ALLOC_V1_FIELD_BYTES[i];
220
221         return DIV_ROUND_UP(bytes, sizeof(u64));
222 }
223
224 int bch2_alloc_v1_invalid(const struct bch_fs *c, struct bkey_s_c k,
225                           int rw, struct printbuf *err)
226 {
227         struct bkey_s_c_alloc a = bkey_s_c_to_alloc(k);
228
229         /* allow for unknown fields */
230         if (bkey_val_u64s(a.k) < bch_alloc_v1_val_u64s(a.v)) {
231                 prt_printf(err, "incorrect value size (%zu < %u)",
232                        bkey_val_u64s(a.k), bch_alloc_v1_val_u64s(a.v));
233                 return -BCH_ERR_invalid_bkey;
234         }
235
236         return 0;
237 }
238
239 int bch2_alloc_v2_invalid(const struct bch_fs *c, struct bkey_s_c k,
240                           int rw, struct printbuf *err)
241 {
242         struct bkey_alloc_unpacked u;
243
244         if (bch2_alloc_unpack_v2(&u, k)) {
245                 prt_printf(err, "unpack error");
246                 return -BCH_ERR_invalid_bkey;
247         }
248
249         return 0;
250 }
251
252 int bch2_alloc_v3_invalid(const struct bch_fs *c, struct bkey_s_c k,
253                           int rw, struct printbuf *err)
254 {
255         struct bkey_alloc_unpacked u;
256
257         if (bch2_alloc_unpack_v3(&u, k)) {
258                 prt_printf(err, "unpack error");
259                 return -BCH_ERR_invalid_bkey;
260         }
261
262         return 0;
263 }
264
265 int bch2_alloc_v4_invalid(const struct bch_fs *c, struct bkey_s_c k,
266                           int rw, struct printbuf *err)
267 {
268         struct bkey_s_c_alloc_v4 a = bkey_s_c_to_alloc_v4(k);
269
270         if (alloc_v4_u64s(a.v) != bkey_val_u64s(k.k)) {
271                 prt_printf(err, "bad val size (%lu != %u)",
272                        bkey_val_u64s(k.k), alloc_v4_u64s(a.v));
273                 return -BCH_ERR_invalid_bkey;
274         }
275
276         if (!BCH_ALLOC_V4_BACKPOINTERS_START(a.v) &&
277             BCH_ALLOC_V4_NR_BACKPOINTERS(a.v)) {
278                 prt_printf(err, "invalid backpointers_start");
279                 return -BCH_ERR_invalid_bkey;
280         }
281
282         /*
283          * XXX this is wrong, we'll be checking updates that happened from
284          * before BCH_FS_CHECK_BACKPOINTERS_DONE
285          */
286         if (rw == WRITE && test_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags)) {
287                 unsigned i, bp_len = 0;
288
289                 for (i = 0; i < BCH_ALLOC_V4_NR_BACKPOINTERS(a.v); i++)
290                         bp_len += alloc_v4_backpointers_c(a.v)[i].bucket_len;
291
292                 if (bp_len > a.v->dirty_sectors) {
293                         prt_printf(err, "too many backpointers");
294                         return -BCH_ERR_invalid_bkey;
295                 }
296         }
297
298         if (rw == WRITE) {
299                 if (alloc_data_type(*a.v, a.v->data_type) != a.v->data_type) {
300                         prt_printf(err, "invalid data type (got %u should be %u)",
301                                a.v->data_type, alloc_data_type(*a.v, a.v->data_type));
302                         return -BCH_ERR_invalid_bkey;
303                 }
304
305                 switch (a.v->data_type) {
306                 case BCH_DATA_free:
307                 case BCH_DATA_need_gc_gens:
308                 case BCH_DATA_need_discard:
309                         if (a.v->dirty_sectors ||
310                             a.v->cached_sectors ||
311                             a.v->stripe) {
312                                 prt_printf(err, "empty data type free but have data");
313                                 return -BCH_ERR_invalid_bkey;
314                         }
315                         break;
316                 case BCH_DATA_sb:
317                 case BCH_DATA_journal:
318                 case BCH_DATA_btree:
319                 case BCH_DATA_user:
320                 case BCH_DATA_parity:
321                         if (!a.v->dirty_sectors) {
322                                 prt_printf(err, "data_type %s but dirty_sectors==0",
323                                        bch2_data_types[a.v->data_type]);
324                                 return -BCH_ERR_invalid_bkey;
325                         }
326                         break;
327                 case BCH_DATA_cached:
328                         if (!a.v->cached_sectors ||
329                             a.v->dirty_sectors ||
330                             a.v->stripe) {
331                                 prt_printf(err, "data type inconsistency");
332                                 return -BCH_ERR_invalid_bkey;
333                         }
334
335                         if (!a.v->io_time[READ] &&
336                             test_bit(BCH_FS_CHECK_ALLOC_TO_LRU_REFS_DONE, &c->flags)) {
337                                 prt_printf(err, "cached bucket with read_time == 0");
338                                 return -BCH_ERR_invalid_bkey;
339                         }
340                         break;
341                 case BCH_DATA_stripe:
342                         if (!a.v->stripe) {
343                                 prt_printf(err, "data_type %s but stripe==0",
344                                        bch2_data_types[a.v->data_type]);
345                                 return -BCH_ERR_invalid_bkey;
346                         }
347                         break;
348                 }
349         }
350
351         return 0;
352 }
353
354 static inline u64 swab40(u64 x)
355 {
356         return (((x & 0x00000000ffULL) << 32)|
357                 ((x & 0x000000ff00ULL) << 16)|
358                 ((x & 0x0000ff0000ULL) >>  0)|
359                 ((x & 0x00ff000000ULL) >> 16)|
360                 ((x & 0xff00000000ULL) >> 32));
361 }
362
363 void bch2_alloc_v4_swab(struct bkey_s k)
364 {
365         struct bch_alloc_v4 *a = bkey_s_to_alloc_v4(k).v;
366         struct bch_backpointer *bp, *bps;
367
368         a->journal_seq          = swab64(a->journal_seq);
369         a->flags                = swab32(a->flags);
370         a->dirty_sectors        = swab32(a->dirty_sectors);
371         a->cached_sectors       = swab32(a->cached_sectors);
372         a->io_time[0]           = swab64(a->io_time[0]);
373         a->io_time[1]           = swab64(a->io_time[1]);
374         a->stripe               = swab32(a->stripe);
375         a->nr_external_backpointers = swab32(a->nr_external_backpointers);
376
377         bps = alloc_v4_backpointers(a);
378         for (bp = bps; bp < bps + BCH_ALLOC_V4_NR_BACKPOINTERS(a); bp++) {
379                 bp->bucket_offset       = swab40(bp->bucket_offset);
380                 bp->bucket_len          = swab32(bp->bucket_len);
381                 bch2_bpos_swab(&bp->pos);
382         }
383 }
384
385 void bch2_alloc_to_text(struct printbuf *out, struct bch_fs *c, struct bkey_s_c k)
386 {
387         struct bch_alloc_v4 _a;
388         const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, &_a);
389         unsigned i;
390
391         prt_newline(out);
392         printbuf_indent_add(out, 2);
393
394         prt_printf(out, "gen %u oldest_gen %u data_type %s",
395                a->gen, a->oldest_gen,
396                a->data_type < BCH_DATA_NR
397                ? bch2_data_types[a->data_type]
398                : "(invalid data type)");
399         prt_newline(out);
400         prt_printf(out, "journal_seq       %llu",       a->journal_seq);
401         prt_newline(out);
402         prt_printf(out, "need_discard      %llu",       BCH_ALLOC_V4_NEED_DISCARD(a));
403         prt_newline(out);
404         prt_printf(out, "need_inc_gen      %llu",       BCH_ALLOC_V4_NEED_INC_GEN(a));
405         prt_newline(out);
406         prt_printf(out, "dirty_sectors     %u", a->dirty_sectors);
407         prt_newline(out);
408         prt_printf(out, "cached_sectors    %u", a->cached_sectors);
409         prt_newline(out);
410         prt_printf(out, "stripe            %u", a->stripe);
411         prt_newline(out);
412         prt_printf(out, "stripe_redundancy %u", a->stripe_redundancy);
413         prt_newline(out);
414         prt_printf(out, "io_time[READ]     %llu",       a->io_time[READ]);
415         prt_newline(out);
416         prt_printf(out, "io_time[WRITE]    %llu",       a->io_time[WRITE]);
417         prt_newline(out);
418
419         if (k.k->type == KEY_TYPE_alloc_v4) {
420                 struct bkey_s_c_alloc_v4 a_raw = bkey_s_c_to_alloc_v4(k);
421                 const struct bch_backpointer *bps = alloc_v4_backpointers_c(a_raw.v);
422
423                 prt_printf(out, "bp_start          %llu", BCH_ALLOC_V4_BACKPOINTERS_START(a_raw.v));
424                 prt_newline(out);
425
426                 prt_printf(out, "backpointers:     %llu", BCH_ALLOC_V4_NR_BACKPOINTERS(a_raw.v));
427                 printbuf_indent_add(out, 2);
428
429                 for (i = 0; i < BCH_ALLOC_V4_NR_BACKPOINTERS(a_raw.v); i++) {
430                         prt_newline(out);
431                         bch2_backpointer_to_text(out, &bps[i]);
432                 }
433
434                 printbuf_indent_sub(out, 2);
435         }
436
437         printbuf_indent_sub(out, 2);
438 }
439
440 void __bch2_alloc_to_v4(struct bkey_s_c k, struct bch_alloc_v4 *out)
441 {
442         if (k.k->type == KEY_TYPE_alloc_v4) {
443                 void *src, *dst;
444
445                 *out = *bkey_s_c_to_alloc_v4(k).v;
446
447                 src = alloc_v4_backpointers(out);
448                 SET_BCH_ALLOC_V4_BACKPOINTERS_START(out, BCH_ALLOC_V4_U64s);
449                 dst = alloc_v4_backpointers(out);
450
451                 if (src < dst)
452                         memset(src, 0, dst - src);
453         } else {
454                 struct bkey_alloc_unpacked u = bch2_alloc_unpack(k);
455
456                 *out = (struct bch_alloc_v4) {
457                         .journal_seq            = u.journal_seq,
458                         .flags                  = u.need_discard,
459                         .gen                    = u.gen,
460                         .oldest_gen             = u.oldest_gen,
461                         .data_type              = u.data_type,
462                         .stripe_redundancy      = u.stripe_redundancy,
463                         .dirty_sectors          = u.dirty_sectors,
464                         .cached_sectors         = u.cached_sectors,
465                         .io_time[READ]          = u.read_time,
466                         .io_time[WRITE]         = u.write_time,
467                         .stripe                 = u.stripe,
468                 };
469
470                 SET_BCH_ALLOC_V4_BACKPOINTERS_START(out, BCH_ALLOC_V4_U64s);
471         }
472 }
473
474 static noinline struct bkey_i_alloc_v4 *
475 __bch2_alloc_to_v4_mut(struct btree_trans *trans, struct bkey_s_c k)
476 {
477         struct bkey_i_alloc_v4 *ret;
478         if (k.k->type == KEY_TYPE_alloc_v4) {
479                 struct bkey_s_c_alloc_v4 a = bkey_s_c_to_alloc_v4(k);
480                 unsigned bytes = sizeof(struct bkey_i_alloc_v4) +
481                         BCH_ALLOC_V4_NR_BACKPOINTERS(a.v) *
482                         sizeof(struct bch_backpointer);
483                 void *src, *dst;
484
485                 /*
486                  * Reserve space for one more backpointer here:
487                  * Not sketchy at doing it this way, nope...
488                  */
489                 ret = bch2_trans_kmalloc(trans, bytes + sizeof(struct bch_backpointer));
490                 if (IS_ERR(ret))
491                         return ret;
492
493                 bkey_reassemble(&ret->k_i, k);
494
495                 src = alloc_v4_backpointers(&ret->v);
496                 SET_BCH_ALLOC_V4_BACKPOINTERS_START(&ret->v, BCH_ALLOC_V4_U64s);
497                 dst = alloc_v4_backpointers(&ret->v);
498
499                 memmove(dst, src, BCH_ALLOC_V4_NR_BACKPOINTERS(&ret->v) *
500                         sizeof(struct bch_backpointer));
501                 if (src < dst)
502                         memset(src, 0, dst - src);
503                 set_alloc_v4_u64s(ret);
504         } else {
505                 ret = bch2_trans_kmalloc(trans, sizeof(struct bkey_i_alloc_v4) +
506                                          sizeof(struct bch_backpointer));
507                 if (IS_ERR(ret))
508                         return ret;
509
510                 bkey_alloc_v4_init(&ret->k_i);
511                 ret->k.p = k.k->p;
512                 bch2_alloc_to_v4(k, &ret->v);
513         }
514         return ret;
515 }
516
517 static inline struct bkey_i_alloc_v4 *bch2_alloc_to_v4_mut_inlined(struct btree_trans *trans, struct bkey_s_c k)
518 {
519         if (likely(k.k->type == KEY_TYPE_alloc_v4) &&
520             BCH_ALLOC_V4_BACKPOINTERS_START(bkey_s_c_to_alloc_v4(k).v) == BCH_ALLOC_V4_U64s) {
521                 /*
522                  * Reserve space for one more backpointer here:
523                  * Not sketchy at doing it this way, nope...
524                  */
525                 struct bkey_i_alloc_v4 *ret =
526                         bch2_trans_kmalloc_nomemzero(trans, bkey_bytes(k.k) + sizeof(struct bch_backpointer));
527                 if (!IS_ERR(ret))
528                         bkey_reassemble(&ret->k_i, k);
529                 return ret;
530         }
531
532         return __bch2_alloc_to_v4_mut(trans, k);
533 }
534
535 struct bkey_i_alloc_v4 *bch2_alloc_to_v4_mut(struct btree_trans *trans, struct bkey_s_c k)
536 {
537         return bch2_alloc_to_v4_mut_inlined(trans, k);
538 }
539
540 struct bkey_i_alloc_v4 *
541 bch2_trans_start_alloc_update(struct btree_trans *trans, struct btree_iter *iter,
542                               struct bpos pos)
543 {
544         struct bkey_s_c k;
545         struct bkey_i_alloc_v4 *a;
546         int ret;
547
548         bch2_trans_iter_init(trans, iter, BTREE_ID_alloc, pos,
549                              BTREE_ITER_WITH_UPDATES|
550                              BTREE_ITER_CACHED|
551                              BTREE_ITER_INTENT);
552         k = bch2_btree_iter_peek_slot(iter);
553         ret = bkey_err(k);
554         if (unlikely(ret))
555                 goto err;
556
557         a = bch2_alloc_to_v4_mut_inlined(trans, k);
558         ret = PTR_ERR_OR_ZERO(a);
559         if (unlikely(ret))
560                 goto err;
561         return a;
562 err:
563         bch2_trans_iter_exit(trans, iter);
564         return ERR_PTR(ret);
565 }
566
567 int bch2_alloc_read(struct bch_fs *c)
568 {
569         struct btree_trans trans;
570         struct btree_iter iter;
571         struct bkey_s_c k;
572         struct bch_alloc_v4 a;
573         struct bch_dev *ca;
574         int ret;
575
576         bch2_trans_init(&trans, c, 0, 0);
577
578         for_each_btree_key(&trans, iter, BTREE_ID_alloc, POS_MIN,
579                            BTREE_ITER_PREFETCH, k, ret) {
580                 /*
581                  * Not a fsck error because this is checked/repaired by
582                  * bch2_check_alloc_key() which runs later:
583                  */
584                 if (!bch2_dev_bucket_exists(c, k.k->p))
585                         continue;
586
587                 ca = bch_dev_bkey_exists(c, k.k->p.inode);
588
589                 *bucket_gen(ca, k.k->p.offset) = bch2_alloc_to_v4(k, &a)->gen;
590         }
591         bch2_trans_iter_exit(&trans, &iter);
592
593         bch2_trans_exit(&trans);
594
595         if (ret)
596                 bch_err(c, "error reading alloc info: %s", bch2_err_str(ret));
597
598         return ret;
599 }
600
601 static struct bpos alloc_gens_pos(struct bpos pos, unsigned *offset)
602 {
603         *offset = pos.offset & KEY_TYPE_BUCKET_GENS_MASK;
604
605         pos.offset >>= KEY_TYPE_BUCKET_GENS_BITS;
606         return pos;
607 }
608
609 static struct bpos bucket_gens_pos_to_alloc(struct bpos pos, unsigned offset)
610 {
611         pos.offset <<= KEY_TYPE_BUCKET_GENS_BITS;
612         pos.offset += offset;
613         return pos;
614 }
615
616 static unsigned alloc_gen(struct bkey_s_c k, unsigned offset)
617 {
618         return k.k->type == KEY_TYPE_bucket_gens
619                 ? bkey_s_c_to_bucket_gens(k).v->gens[offset]
620                 : 0;
621 }
622
623 int bch2_bucket_gens_invalid(const struct bch_fs *c, struct bkey_s_c k,
624                              int rw, struct printbuf *err)
625 {
626         if (bkey_val_bytes(k.k) != sizeof(struct bch_bucket_gens)) {
627                 prt_printf(err, "bad val size (%lu != %zu)",
628                        bkey_val_bytes(k.k), sizeof(struct bch_bucket_gens));
629                 return -BCH_ERR_invalid_bkey;
630         }
631
632         return 0;
633 }
634
635 void bch2_bucket_gens_to_text(struct printbuf *out, struct bch_fs *c, struct bkey_s_c k)
636 {
637         struct bkey_s_c_bucket_gens g = bkey_s_c_to_bucket_gens(k);
638         unsigned i;
639
640         for (i = 0; i < ARRAY_SIZE(g.v->gens); i++) {
641                 if (i)
642                         prt_char(out, ' ');
643                 prt_printf(out, "%u", g.v->gens[i]);
644         }
645 }
646
647 int bch2_bucket_gens_init(struct bch_fs *c)
648 {
649         struct btree_trans trans;
650         struct btree_iter iter;
651         struct bkey_s_c k;
652         struct bch_alloc_v4 a;
653         struct bkey_i_bucket_gens g;
654         bool have_bucket_gens_key = false;
655         unsigned offset;
656         struct bpos pos;
657         u8 gen;
658         int ret;
659
660         bch2_trans_init(&trans, c, 0, 0);
661
662         for_each_btree_key(&trans, iter, BTREE_ID_alloc, POS_MIN,
663                            BTREE_ITER_PREFETCH, k, ret) {
664                 /*
665                  * Not a fsck error because this is checked/repaired by
666                  * bch2_check_alloc_key() which runs later:
667                  */
668                 if (!bch2_dev_bucket_exists(c, k.k->p))
669                         continue;
670
671                 gen = bch2_alloc_to_v4(k, &a)->gen;
672                 pos = alloc_gens_pos(iter.pos, &offset);
673
674                 if (have_bucket_gens_key && bkey_cmp(iter.pos, pos)) {
675                         ret = commit_do(&trans, NULL, NULL,
676                                         BTREE_INSERT_NOFAIL|
677                                         BTREE_INSERT_LAZY_RW,
678                                 __bch2_btree_insert(&trans, BTREE_ID_bucket_gens, &g.k_i));
679                         if (ret)
680                                 break;
681                         have_bucket_gens_key = false;
682                 }
683
684                 if (!have_bucket_gens_key) {
685                         bkey_bucket_gens_init(&g.k_i);
686                         g.k.p = pos;
687                         have_bucket_gens_key = true;
688                 }
689
690                 g.v.gens[offset] = gen;
691         }
692         bch2_trans_iter_exit(&trans, &iter);
693
694         if (have_bucket_gens_key && !ret)
695                 ret = commit_do(&trans, NULL, NULL,
696                                 BTREE_INSERT_NOFAIL|
697                                 BTREE_INSERT_LAZY_RW,
698                         __bch2_btree_insert(&trans, BTREE_ID_bucket_gens, &g.k_i));
699
700         bch2_trans_exit(&trans);
701
702         if (ret)
703                 bch_err(c, "%s: error %s", __func__, bch2_err_str(ret));
704
705         return ret;
706 }
707
708 int bch2_bucket_gens_read(struct bch_fs *c)
709 {
710         struct btree_trans trans;
711         struct btree_iter iter;
712         struct bkey_s_c k;
713         const struct bch_bucket_gens *g;
714         struct bch_dev *ca;
715         u64 b;
716         int ret;
717
718         bch2_trans_init(&trans, c, 0, 0);
719
720         for_each_btree_key(&trans, iter, BTREE_ID_bucket_gens, POS_MIN,
721                            BTREE_ITER_PREFETCH, k, ret) {
722                 u64 start = bucket_gens_pos_to_alloc(k.k->p, 0).offset;
723                 u64 end = bucket_gens_pos_to_alloc(bpos_nosnap_successor(k.k->p), 0).offset;
724
725                 if (k.k->type != KEY_TYPE_bucket_gens)
726                         continue;
727
728                 g = bkey_s_c_to_bucket_gens(k).v;
729
730                 /*
731                  * Not a fsck error because this is checked/repaired by
732                  * bch2_check_alloc_key() which runs later:
733                  */
734                 if (!bch2_dev_exists2(c, k.k->p.inode))
735                         continue;
736
737                 ca = bch_dev_bkey_exists(c, k.k->p.inode);
738
739                 for (b = max_t(u64, ca->mi.first_bucket, start);
740                      b < min_t(u64, ca->mi.nbuckets, end);
741                      b++)
742                         *bucket_gen(ca, b) = g->gens[b & KEY_TYPE_BUCKET_GENS_MASK];
743         }
744         bch2_trans_iter_exit(&trans, &iter);
745
746         bch2_trans_exit(&trans);
747
748         if (ret)
749                 bch_err(c, "error reading alloc info: %s", bch2_err_str(ret));
750
751         return ret;
752 }
753
754 /* Free space/discard btree: */
755
756 static int bch2_bucket_do_index(struct btree_trans *trans,
757                                 struct bkey_s_c alloc_k,
758                                 const struct bch_alloc_v4 *a,
759                                 bool set)
760 {
761         struct bch_fs *c = trans->c;
762         struct bch_dev *ca = bch_dev_bkey_exists(c, alloc_k.k->p.inode);
763         struct btree_iter iter;
764         struct bkey_s_c old;
765         struct bkey_i *k;
766         enum btree_id btree;
767         enum bch_bkey_type old_type = !set ? KEY_TYPE_set : KEY_TYPE_deleted;
768         enum bch_bkey_type new_type =  set ? KEY_TYPE_set : KEY_TYPE_deleted;
769         struct printbuf buf = PRINTBUF;
770         int ret;
771
772         if (a->data_type != BCH_DATA_free &&
773             a->data_type != BCH_DATA_need_discard)
774                 return 0;
775
776         k = bch2_trans_kmalloc_nomemzero(trans, sizeof(*k));
777         if (IS_ERR(k))
778                 return PTR_ERR(k);
779
780         bkey_init(&k->k);
781         k->k.type = new_type;
782
783         switch (a->data_type) {
784         case BCH_DATA_free:
785                 btree = BTREE_ID_freespace;
786                 k->k.p = alloc_freespace_pos(alloc_k.k->p, *a);
787                 bch2_key_resize(&k->k, 1);
788                 break;
789         case BCH_DATA_need_discard:
790                 btree = BTREE_ID_need_discard;
791                 k->k.p = alloc_k.k->p;
792                 break;
793         default:
794                 return 0;
795         }
796
797         bch2_trans_iter_init(trans, &iter, btree,
798                              bkey_start_pos(&k->k),
799                              BTREE_ITER_INTENT);
800         old = bch2_btree_iter_peek_slot(&iter);
801         ret = bkey_err(old);
802         if (ret)
803                 goto err;
804
805         if (ca->mi.freespace_initialized &&
806             test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags) &&
807             bch2_trans_inconsistent_on(old.k->type != old_type, trans,
808                         "incorrect key when %s %s btree (got %s should be %s)\n"
809                         "  for %s",
810                         set ? "setting" : "clearing",
811                         bch2_btree_ids[btree],
812                         bch2_bkey_types[old.k->type],
813                         bch2_bkey_types[old_type],
814                         (bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
815                 ret = -EIO;
816                 goto err;
817         }
818
819         ret = bch2_trans_update(trans, &iter, k, 0);
820 err:
821         bch2_trans_iter_exit(trans, &iter);
822         printbuf_exit(&buf);
823         return ret;
824 }
825
826 static noinline int bch2_bucket_gen_update(struct btree_trans *trans,
827                                            struct bpos bucket, u8 gen)
828 {
829         struct btree_iter iter;
830         unsigned offset;
831         struct bpos pos = alloc_gens_pos(bucket, &offset);
832         struct bkey_i_bucket_gens *g;
833         struct bkey_s_c k;
834         int ret;
835
836         g = bch2_trans_kmalloc(trans, sizeof(*g));
837         ret = PTR_ERR_OR_ZERO(g);
838         if (ret)
839                 return ret;
840
841         bch2_trans_iter_init(trans, &iter, BTREE_ID_bucket_gens, pos,
842                              BTREE_ITER_INTENT|
843                              BTREE_ITER_WITH_UPDATES);
844         k = bch2_btree_iter_peek_slot(&iter);
845         ret = bkey_err(k);
846         if (ret)
847                 goto err;
848
849         if (k.k->type != KEY_TYPE_bucket_gens) {
850                 bkey_bucket_gens_init(&g->k_i);
851                 g->k.p = iter.pos;
852         } else {
853                 bkey_reassemble(&g->k_i, k);
854         }
855
856         g->v.gens[offset] = gen;
857
858         ret = bch2_trans_update(trans, &iter, &g->k_i, 0);
859 err:
860         bch2_trans_iter_exit(trans, &iter);
861         return ret;
862 }
863
864 int bch2_trans_mark_alloc(struct btree_trans *trans,
865                           enum btree_id btree_id, unsigned level,
866                           struct bkey_s_c old, struct bkey_i *new,
867                           unsigned flags)
868 {
869         struct bch_fs *c = trans->c;
870         struct bch_alloc_v4 old_a_convert, *new_a;
871         const struct bch_alloc_v4 *old_a;
872         u64 old_lru, new_lru;
873         int ret = 0;
874
875         /*
876          * Deletion only happens in the device removal path, with
877          * BTREE_TRIGGER_NORUN:
878          */
879         BUG_ON(new->k.type != KEY_TYPE_alloc_v4);
880
881         old_a = bch2_alloc_to_v4(old, &old_a_convert);
882         new_a = &bkey_i_to_alloc_v4(new)->v;
883
884         new_a->data_type = alloc_data_type(*new_a, new_a->data_type);
885
886         if (new_a->dirty_sectors > old_a->dirty_sectors ||
887             new_a->cached_sectors > old_a->cached_sectors) {
888                 new_a->io_time[READ] = max_t(u64, 1, atomic64_read(&c->io_clock[READ].now));
889                 new_a->io_time[WRITE]= max_t(u64, 1, atomic64_read(&c->io_clock[WRITE].now));
890                 SET_BCH_ALLOC_V4_NEED_INC_GEN(new_a, true);
891                 SET_BCH_ALLOC_V4_NEED_DISCARD(new_a, true);
892         }
893
894         if (data_type_is_empty(new_a->data_type) &&
895             BCH_ALLOC_V4_NEED_INC_GEN(new_a) &&
896             !bch2_bucket_is_open_safe(c, new->k.p.inode, new->k.p.offset)) {
897                 new_a->gen++;
898                 SET_BCH_ALLOC_V4_NEED_INC_GEN(new_a, false);
899         }
900
901         if (old_a->data_type != new_a->data_type ||
902             (new_a->data_type == BCH_DATA_free &&
903              alloc_freespace_genbits(*old_a) != alloc_freespace_genbits(*new_a))) {
904                 ret =   bch2_bucket_do_index(trans, old, old_a, false) ?:
905                         bch2_bucket_do_index(trans, bkey_i_to_s_c(new), new_a, true);
906                 if (ret)
907                         return ret;
908         }
909
910         if (new_a->data_type == BCH_DATA_cached &&
911             !new_a->io_time[READ])
912                 new_a->io_time[READ] = max_t(u64, 1, atomic64_read(&c->io_clock[READ].now));
913
914         old_lru = alloc_lru_idx(*old_a);
915         new_lru = alloc_lru_idx(*new_a);
916
917         if (old_lru != new_lru) {
918                 ret = bch2_lru_change(trans, new->k.p.inode,
919                                       bucket_to_u64(new->k.p),
920                                       old_lru, new_lru);
921                 if (ret)
922                         return ret;
923         }
924
925         if (old_a->gen != new_a->gen) {
926                 ret = bch2_bucket_gen_update(trans, new->k.p, new_a->gen);
927                 if (ret)
928                         return ret;
929         }
930
931         return 0;
932 }
933
934 /*
935  * This synthesizes deleted extents for holes, similar to BTREE_ITER_SLOTS for
936  * extents style btrees, but works on non-extents btrees:
937  */
938 struct bkey_s_c bch2_get_key_or_hole(struct btree_iter *iter, struct bpos end, struct bkey *hole)
939 {
940         struct bkey_s_c k = bch2_btree_iter_peek_slot(iter);
941
942         if (bkey_err(k))
943                 return k;
944
945         if (k.k->type) {
946                 return k;
947         } else {
948                 struct btree_iter iter2;
949                 struct bpos next;
950
951                 bch2_trans_copy_iter(&iter2, iter);
952                 k = bch2_btree_iter_peek_upto(&iter2,
953                                 bkey_min(bkey_min(end,
954                                                   iter->path->l[0].b->key.k.p),
955                                                   POS(iter->pos.inode, iter->pos.offset + U32_MAX - 1)));
956                 next = iter2.pos;
957                 bch2_trans_iter_exit(iter->trans, &iter2);
958
959                 BUG_ON(next.offset >= iter->pos.offset + U32_MAX);
960
961                 if (bkey_err(k))
962                         return k;
963
964                 bkey_init(hole);
965                 hole->p = iter->pos;
966
967                 bch2_key_resize(hole, next.offset - iter->pos.offset);
968                 return (struct bkey_s_c) { hole, NULL };
969         }
970 }
971
972 static bool next_bucket(struct bch_fs *c, struct bpos *bucket)
973 {
974         struct bch_dev *ca;
975         unsigned iter;
976
977         if (bch2_dev_bucket_exists(c, *bucket))
978                 return true;
979
980         if (bch2_dev_exists2(c, bucket->inode)) {
981                 ca = bch_dev_bkey_exists(c, bucket->inode);
982
983                 if (bucket->offset < ca->mi.first_bucket) {
984                         bucket->offset = ca->mi.first_bucket;
985                         return true;
986                 }
987
988                 bucket->inode++;
989                 bucket->offset = 0;
990         }
991
992         rcu_read_lock();
993         iter = bucket->inode;
994         ca = __bch2_next_dev(c, &iter, NULL);
995         if (ca)
996                 bucket->offset = ca->mi.first_bucket;
997         rcu_read_unlock();
998
999         return ca != NULL;
1000 }
1001
1002 struct bkey_s_c bch2_get_key_or_real_bucket_hole(struct btree_iter *iter, struct bkey *hole)
1003 {
1004         struct bch_fs *c = iter->trans->c;
1005         struct bkey_s_c k;
1006 again:
1007         k = bch2_get_key_or_hole(iter, POS_MAX, hole);
1008         if (bkey_err(k))
1009                 return k;
1010
1011         if (!k.k->type) {
1012                 struct bpos bucket = bkey_start_pos(k.k);
1013
1014                 if (!bch2_dev_bucket_exists(c, bucket)) {
1015                         if (!next_bucket(c, &bucket))
1016                                 return bkey_s_c_null;
1017
1018                         bch2_btree_iter_set_pos(iter, bucket);
1019                         goto again;
1020                 }
1021
1022                 if (!bch2_dev_bucket_exists(c, k.k->p)) {
1023                         struct bch_dev *ca = bch_dev_bkey_exists(c, bucket.inode);
1024
1025                         bch2_key_resize(hole, ca->mi.nbuckets - bucket.offset);
1026                 }
1027         }
1028
1029         return k;
1030 }
1031
1032 static int bch2_check_alloc_key(struct btree_trans *trans,
1033                                 struct bkey_s_c alloc_k,
1034                                 struct btree_iter *alloc_iter,
1035                                 struct btree_iter *discard_iter,
1036                                 struct btree_iter *freespace_iter,
1037                                 struct btree_iter *bucket_gens_iter)
1038 {
1039         struct bch_fs *c = trans->c;
1040         struct bch_dev *ca;
1041         struct bch_alloc_v4 a_convert;
1042         const struct bch_alloc_v4 *a;
1043         unsigned discard_key_type, freespace_key_type;
1044         unsigned gens_offset;
1045         struct bkey_s_c k;
1046         struct printbuf buf = PRINTBUF;
1047         int ret;
1048
1049         if (fsck_err_on(!bch2_dev_bucket_exists(c, alloc_k.k->p), c,
1050                         "alloc key for invalid device:bucket %llu:%llu",
1051                         alloc_k.k->p.inode, alloc_k.k->p.offset))
1052                 return bch2_btree_delete_at(trans, alloc_iter, 0);
1053
1054         ca = bch_dev_bkey_exists(c, alloc_k.k->p.inode);
1055         if (!ca->mi.freespace_initialized)
1056                 return 0;
1057
1058         a = bch2_alloc_to_v4(alloc_k, &a_convert);
1059
1060         discard_key_type = a->data_type == BCH_DATA_need_discard ? KEY_TYPE_set : 0;
1061         bch2_btree_iter_set_pos(discard_iter, alloc_k.k->p);
1062         k = bch2_btree_iter_peek_slot(discard_iter);
1063         ret = bkey_err(k);
1064         if (ret)
1065                 goto err;
1066
1067         if (k.k->type != discard_key_type &&
1068             (c->opts.reconstruct_alloc ||
1069              fsck_err(c, "incorrect key in need_discard btree (got %s should be %s)\n"
1070                       "  %s",
1071                       bch2_bkey_types[k.k->type],
1072                       bch2_bkey_types[discard_key_type],
1073                       (bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf)))) {
1074                 struct bkey_i *update =
1075                         bch2_trans_kmalloc(trans, sizeof(*update));
1076
1077                 ret = PTR_ERR_OR_ZERO(update);
1078                 if (ret)
1079                         goto err;
1080
1081                 bkey_init(&update->k);
1082                 update->k.type  = discard_key_type;
1083                 update->k.p     = discard_iter->pos;
1084
1085                 ret = bch2_trans_update(trans, discard_iter, update, 0);
1086                 if (ret)
1087                         goto err;
1088         }
1089
1090         freespace_key_type = a->data_type == BCH_DATA_free ? KEY_TYPE_set : 0;
1091         bch2_btree_iter_set_pos(freespace_iter, alloc_freespace_pos(alloc_k.k->p, *a));
1092         k = bch2_btree_iter_peek_slot(freespace_iter);
1093         ret = bkey_err(k);
1094         if (ret)
1095                 goto err;
1096
1097         if (k.k->type != freespace_key_type &&
1098             (c->opts.reconstruct_alloc ||
1099              fsck_err(c, "incorrect key in freespace btree (got %s should be %s)\n"
1100                       "  %s",
1101                       bch2_bkey_types[k.k->type],
1102                       bch2_bkey_types[freespace_key_type],
1103                       (printbuf_reset(&buf),
1104                        bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf)))) {
1105                 struct bkey_i *update =
1106                         bch2_trans_kmalloc(trans, sizeof(*update));
1107
1108                 ret = PTR_ERR_OR_ZERO(update);
1109                 if (ret)
1110                         goto err;
1111
1112                 bkey_init(&update->k);
1113                 update->k.type  = freespace_key_type;
1114                 update->k.p     = freespace_iter->pos;
1115                 bch2_key_resize(&update->k, 1);
1116
1117                 ret = bch2_trans_update(trans, freespace_iter, update, 0);
1118                 if (ret)
1119                         goto err;
1120         }
1121
1122         bch2_btree_iter_set_pos(bucket_gens_iter, alloc_gens_pos(alloc_k.k->p, &gens_offset));
1123         k = bch2_btree_iter_peek_slot(bucket_gens_iter);
1124         ret = bkey_err(k);
1125         if (ret)
1126                 goto err;
1127
1128         if (a->gen != alloc_gen(k, gens_offset) &&
1129             (c->opts.reconstruct_alloc ||
1130              fsck_err(c, "incorrect gen in bucket_gens btree (got %u should be %u)\n"
1131                       "  %s",
1132                       alloc_gen(k, gens_offset), a->gen,
1133                       (printbuf_reset(&buf),
1134                        bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf)))) {
1135                 struct bkey_i_bucket_gens *g =
1136                         bch2_trans_kmalloc(trans, sizeof(*g));
1137
1138                 ret = PTR_ERR_OR_ZERO(g);
1139                 if (ret)
1140                         goto err;
1141
1142                 if (k.k->type == KEY_TYPE_bucket_gens) {
1143                         bkey_reassemble(&g->k_i, k);
1144                 } else {
1145                         bkey_bucket_gens_init(&g->k_i);
1146                         g->k.p = alloc_gens_pos(alloc_k.k->p, &gens_offset);
1147                 }
1148
1149                 g->v.gens[gens_offset] = a->gen;
1150
1151                 ret = bch2_trans_update(trans, bucket_gens_iter, &g->k_i, 0);
1152                 if (ret)
1153                         goto err;
1154         }
1155 err:
1156 fsck_err:
1157         printbuf_exit(&buf);
1158         return ret;
1159 }
1160
1161 static int bch2_check_alloc_hole_freespace(struct btree_trans *trans,
1162                                  struct bpos start,
1163                                  struct bpos *end,
1164                                  struct btree_iter *freespace_iter)
1165 {
1166         struct bch_fs *c = trans->c;
1167         struct bch_dev *ca;
1168         struct bkey_s_c k;
1169         struct printbuf buf = PRINTBUF;
1170         int ret;
1171
1172         ca = bch_dev_bkey_exists(c, start.inode);
1173         if (!ca->mi.freespace_initialized)
1174                 return 0;
1175
1176         bch2_btree_iter_set_pos(freespace_iter, start);
1177
1178         k = bch2_btree_iter_peek_slot(freespace_iter);
1179         ret = bkey_err(k);
1180         if (ret)
1181                 goto err;
1182
1183         *end = bkey_min(k.k->p, *end);
1184
1185         if (k.k->type != KEY_TYPE_set &&
1186             (c->opts.reconstruct_alloc ||
1187              fsck_err(c, "hole in alloc btree missing in freespace btree\n"
1188                       "  device %llu buckets %llu-%llu",
1189                       freespace_iter->pos.inode,
1190                       freespace_iter->pos.offset,
1191                       end->offset))) {
1192                 struct bkey_i *update =
1193                         bch2_trans_kmalloc(trans, sizeof(*update));
1194
1195                 ret = PTR_ERR_OR_ZERO(update);
1196                 if (ret)
1197                         goto err;
1198
1199                 bkey_init(&update->k);
1200                 update->k.type  = KEY_TYPE_set;
1201                 update->k.p     = freespace_iter->pos;
1202                 bch2_key_resize(&update->k,
1203                                 min_t(u64, U32_MAX, end->offset -
1204                                       freespace_iter->pos.offset));
1205
1206                 ret = bch2_trans_update(trans, freespace_iter, update, 0);
1207                 if (ret)
1208                         goto err;
1209         }
1210 err:
1211 fsck_err:
1212         printbuf_exit(&buf);
1213         return ret;
1214 }
1215
1216 static int bch2_check_alloc_hole_bucket_gens(struct btree_trans *trans,
1217                                  struct bpos start,
1218                                  struct bpos *end,
1219                                  struct btree_iter *bucket_gens_iter)
1220 {
1221         struct bch_fs *c = trans->c;
1222         struct bkey_s_c k;
1223         struct printbuf buf = PRINTBUF;
1224         unsigned i, gens_offset, gens_end_offset;
1225         int ret;
1226
1227         if (c->sb.version < bcachefs_metadata_version_bucket_gens &&
1228             !c->opts.version_upgrade)
1229                 return 0;
1230
1231         bch2_btree_iter_set_pos(bucket_gens_iter, alloc_gens_pos(start, &gens_offset));
1232
1233         k = bch2_btree_iter_peek_slot(bucket_gens_iter);
1234         ret = bkey_err(k);
1235         if (ret)
1236                 goto err;
1237
1238         if (bkey_cmp(alloc_gens_pos(start, &gens_offset),
1239                      alloc_gens_pos(*end,  &gens_end_offset)))
1240                 gens_end_offset = KEY_TYPE_BUCKET_GENS_NR;
1241
1242         if (k.k->type == KEY_TYPE_bucket_gens) {
1243                 struct bkey_i_bucket_gens g;
1244                 bool need_update = false;
1245
1246                 bkey_reassemble(&g.k_i, k);
1247
1248                 for (i = gens_offset; i < gens_end_offset; i++) {
1249                         if (fsck_err_on(g.v.gens[i], c,
1250                                         "hole in alloc btree at %llu:%llu with nonzero gen in bucket_gens btree (%u)",
1251                                         bucket_gens_pos_to_alloc(k.k->p, i).inode,
1252                                         bucket_gens_pos_to_alloc(k.k->p, i).offset,
1253                                         g.v.gens[i])) {
1254                                 g.v.gens[i] = 0;
1255                                 need_update = true;
1256                         }
1257                 }
1258
1259                 if (need_update) {
1260                         struct bkey_i *k = bch2_trans_kmalloc(trans, sizeof(g));
1261
1262                         ret = PTR_ERR_OR_ZERO(k);
1263                         if (ret)
1264                                 goto err;
1265
1266                         memcpy(k, &g, sizeof(g));
1267
1268                         ret = bch2_trans_update(trans, bucket_gens_iter, k, 0);
1269                         if (ret)
1270                                 goto err;
1271                 }
1272         }
1273
1274         *end = bkey_min(*end, bucket_gens_pos_to_alloc(bpos_nosnap_successor(k.k->p), 0));
1275 err:
1276 fsck_err:
1277         printbuf_exit(&buf);
1278         return ret;
1279 }
1280
1281 static int bch2_check_discard_freespace_key(struct btree_trans *trans,
1282                                             struct btree_iter *iter)
1283 {
1284         struct bch_fs *c = trans->c;
1285         struct btree_iter alloc_iter;
1286         struct bkey_s_c alloc_k;
1287         struct bch_alloc_v4 a_convert;
1288         const struct bch_alloc_v4 *a;
1289         u64 genbits;
1290         struct bpos pos;
1291         enum bch_data_type state = iter->btree_id == BTREE_ID_need_discard
1292                 ? BCH_DATA_need_discard
1293                 : BCH_DATA_free;
1294         struct printbuf buf = PRINTBUF;
1295         int ret;
1296
1297         pos = iter->pos;
1298         pos.offset &= ~(~0ULL << 56);
1299         genbits = iter->pos.offset & (~0ULL << 56);
1300
1301         bch2_trans_iter_init(trans, &alloc_iter, BTREE_ID_alloc, pos, 0);
1302
1303         if (fsck_err_on(!bch2_dev_bucket_exists(c, pos), c,
1304                         "entry in %s btree for nonexistant dev:bucket %llu:%llu",
1305                         bch2_btree_ids[iter->btree_id], pos.inode, pos.offset))
1306                 goto delete;
1307
1308         alloc_k = bch2_btree_iter_peek_slot(&alloc_iter);
1309         ret = bkey_err(alloc_k);
1310         if (ret)
1311                 goto err;
1312
1313         a = bch2_alloc_to_v4(alloc_k, &a_convert);
1314
1315         if (fsck_err_on(a->data_type != state ||
1316                         (state == BCH_DATA_free &&
1317                          genbits != alloc_freespace_genbits(*a)), c,
1318                         "%s\n  incorrectly set in %s index (free %u, genbits %llu should be %llu)",
1319                         (bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf),
1320                         bch2_btree_ids[iter->btree_id],
1321                         a->data_type == state,
1322                         genbits >> 56, alloc_freespace_genbits(*a) >> 56))
1323                 goto delete;
1324 out:
1325 err:
1326 fsck_err:
1327         bch2_trans_iter_exit(trans, &alloc_iter);
1328         printbuf_exit(&buf);
1329         return ret;
1330 delete:
1331         ret = bch2_btree_delete_extent_at(trans, iter,
1332                         iter->btree_id == BTREE_ID_freespace ? 1 : 0, 0);
1333         goto out;
1334 }
1335
1336 /*
1337  * We've already checked that generation numbers in the bucket_gens btree are
1338  * valid for buckets that exist; this just checks for keys for nonexistent
1339  * buckets.
1340  */
1341 static int bch2_check_bucket_gens_key(struct btree_trans *trans,
1342                                       struct btree_iter *iter,
1343                                       struct bkey_s_c k)
1344 {
1345         struct bch_fs *c = trans->c;
1346         struct bkey_i_bucket_gens g;
1347         struct bch_dev *ca;
1348         u64 start = bucket_gens_pos_to_alloc(k.k->p, 0).offset;
1349         u64 end = bucket_gens_pos_to_alloc(bpos_nosnap_successor(k.k->p), 0).offset;
1350         u64 b;
1351         bool need_update = false;
1352         struct printbuf buf = PRINTBUF;
1353         int ret = 0;
1354
1355         BUG_ON(k.k->type != KEY_TYPE_bucket_gens);
1356         bkey_reassemble(&g.k_i, k);
1357
1358         if (fsck_err_on(!bch2_dev_exists2(c, k.k->p.inode), c,
1359                         "bucket_gens key for invalid device:\n  %s",
1360                         (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
1361                 ret = bch2_btree_delete_at(trans, iter, 0);
1362                 goto out;
1363         }
1364
1365         ca = bch_dev_bkey_exists(c, k.k->p.inode);
1366         if (fsck_err_on(end <= ca->mi.first_bucket ||
1367                         start >= ca->mi.nbuckets, c,
1368                         "bucket_gens key for invalid buckets:\n  %s",
1369                         (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
1370                 ret = bch2_btree_delete_at(trans, iter, 0);
1371                 goto out;
1372         }
1373
1374         for (b = start; b < ca->mi.first_bucket; b++)
1375                 if (fsck_err_on(g.v.gens[b & KEY_TYPE_BUCKET_GENS_MASK], c,
1376                                 "bucket_gens key has nonzero gen for invalid bucket")) {
1377                         g.v.gens[b & KEY_TYPE_BUCKET_GENS_MASK] = 0;
1378                         need_update = true;
1379                 }
1380
1381         for (b = ca->mi.nbuckets; b < end; b++)
1382                 if (fsck_err_on(g.v.gens[b & KEY_TYPE_BUCKET_GENS_MASK], c,
1383                                 "bucket_gens key has nonzero gen for invalid bucket")) {
1384                         g.v.gens[b & KEY_TYPE_BUCKET_GENS_MASK] = 0;
1385                         need_update = true;
1386                 }
1387
1388         if (need_update) {
1389                 struct bkey_i *k;
1390
1391                 k = bch2_trans_kmalloc(trans, sizeof(g));
1392                 ret = PTR_ERR_OR_ZERO(k);
1393                 if (ret)
1394                         goto out;
1395
1396                 memcpy(k, &g, sizeof(g));
1397                 ret = bch2_trans_update(trans, iter, k, 0);
1398         }
1399 out:
1400 fsck_err:
1401         printbuf_exit(&buf);
1402         return ret;
1403 }
1404
1405 int bch2_check_alloc_info(struct bch_fs *c)
1406 {
1407         struct btree_trans trans;
1408         struct btree_iter iter, discard_iter, freespace_iter, bucket_gens_iter;
1409         struct bkey hole;
1410         struct bkey_s_c k;
1411         int ret = 0;
1412
1413         bch2_trans_init(&trans, c, 0, 0);
1414
1415         bch2_trans_iter_init(&trans, &iter, BTREE_ID_alloc, POS_MIN,
1416                              BTREE_ITER_PREFETCH);
1417         bch2_trans_iter_init(&trans, &discard_iter, BTREE_ID_need_discard, POS_MIN,
1418                              BTREE_ITER_PREFETCH);
1419         bch2_trans_iter_init(&trans, &freespace_iter, BTREE_ID_freespace, POS_MIN,
1420                              BTREE_ITER_PREFETCH);
1421         bch2_trans_iter_init(&trans, &bucket_gens_iter, BTREE_ID_bucket_gens, POS_MIN,
1422                              BTREE_ITER_PREFETCH);
1423
1424         while (1) {
1425                 struct bpos next;
1426
1427                 bch2_trans_begin(&trans);
1428
1429                 k = bch2_get_key_or_real_bucket_hole(&iter, &hole);
1430                 ret = bkey_err(k);
1431                 if (ret)
1432                         goto bkey_err;
1433
1434                 if (!k.k)
1435                         break;
1436
1437                 if (k.k->type) {
1438                         next = bpos_nosnap_successor(k.k->p);
1439
1440                         ret = bch2_check_alloc_key(&trans,
1441                                                    k, &iter,
1442                                                    &discard_iter,
1443                                                    &freespace_iter,
1444                                                    &bucket_gens_iter);
1445                         if (ret)
1446                                 goto bkey_err;
1447                 } else {
1448                         next = k.k->p;
1449
1450                         ret = bch2_check_alloc_hole_freespace(&trans,
1451                                                     bkey_start_pos(k.k),
1452                                                     &next,
1453                                                     &freespace_iter) ?:
1454                                 bch2_check_alloc_hole_bucket_gens(&trans,
1455                                                     bkey_start_pos(k.k),
1456                                                     &next,
1457                                                     &bucket_gens_iter);
1458                         if (ret)
1459                                 goto bkey_err;
1460                 }
1461
1462                 ret = bch2_trans_commit(&trans, NULL, NULL,
1463                                         BTREE_INSERT_NOFAIL|
1464                                         BTREE_INSERT_LAZY_RW);
1465                 if (ret)
1466                         goto bkey_err;
1467
1468                 bch2_btree_iter_set_pos(&iter, next);
1469 bkey_err:
1470                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
1471                         continue;
1472                 if (ret)
1473                         break;
1474         }
1475         bch2_trans_iter_exit(&trans, &bucket_gens_iter);
1476         bch2_trans_iter_exit(&trans, &freespace_iter);
1477         bch2_trans_iter_exit(&trans, &discard_iter);
1478         bch2_trans_iter_exit(&trans, &iter);
1479
1480         if (ret < 0)
1481                 goto err;
1482
1483         ret = for_each_btree_key_commit(&trans, iter,
1484                         BTREE_ID_need_discard, POS_MIN,
1485                         BTREE_ITER_PREFETCH, k,
1486                         NULL, NULL, BTREE_INSERT_NOFAIL|BTREE_INSERT_LAZY_RW,
1487                 bch2_check_discard_freespace_key(&trans, &iter)) ?:
1488               for_each_btree_key_commit(&trans, iter,
1489                         BTREE_ID_freespace, POS_MIN,
1490                         BTREE_ITER_PREFETCH, k,
1491                         NULL, NULL, BTREE_INSERT_NOFAIL|BTREE_INSERT_LAZY_RW,
1492                 bch2_check_discard_freespace_key(&trans, &iter)) ?:
1493               for_each_btree_key_commit(&trans, iter,
1494                         BTREE_ID_bucket_gens, POS_MIN,
1495                         BTREE_ITER_PREFETCH, k,
1496                         NULL, NULL, BTREE_INSERT_NOFAIL|BTREE_INSERT_LAZY_RW,
1497                 bch2_check_bucket_gens_key(&trans, &iter, k));
1498 err:
1499         bch2_trans_exit(&trans);
1500         return ret < 0 ? ret : 0;
1501 }
1502
1503 static int bch2_check_alloc_to_lru_ref(struct btree_trans *trans,
1504                                        struct btree_iter *alloc_iter)
1505 {
1506         struct bch_fs *c = trans->c;
1507         struct btree_iter lru_iter;
1508         struct bch_alloc_v4 a_convert;
1509         const struct bch_alloc_v4 *a;
1510         struct bkey_s_c alloc_k, k;
1511         struct printbuf buf = PRINTBUF;
1512         int ret;
1513
1514         alloc_k = bch2_btree_iter_peek(alloc_iter);
1515         if (!alloc_k.k)
1516                 return 0;
1517
1518         ret = bkey_err(alloc_k);
1519         if (ret)
1520                 return ret;
1521
1522         a = bch2_alloc_to_v4(alloc_k, &a_convert);
1523
1524         if (a->data_type != BCH_DATA_cached)
1525                 return 0;
1526
1527         bch2_trans_iter_init(trans, &lru_iter, BTREE_ID_lru,
1528                              lru_pos(alloc_k.k->p.inode,
1529                                      bucket_to_u64(alloc_k.k->p),
1530                                      a->io_time[READ]), 0);
1531         k = bch2_btree_iter_peek_slot(&lru_iter);
1532         ret = bkey_err(k);
1533         if (ret)
1534                 goto err;
1535
1536         if (fsck_err_on(!a->io_time[READ], c,
1537                         "cached bucket with read_time 0\n"
1538                         "  %s",
1539                 (printbuf_reset(&buf),
1540                  bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf)) ||
1541             fsck_err_on(k.k->type != KEY_TYPE_set, c,
1542                         "missing lru entry\n"
1543                         "  %s",
1544                         (printbuf_reset(&buf),
1545                          bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
1546                 u64 read_time = a->io_time[READ] ?:
1547                         atomic64_read(&c->io_clock[READ].now);
1548
1549                 ret = bch2_lru_set(trans,
1550                                    alloc_k.k->p.inode,
1551                                    bucket_to_u64(alloc_k.k->p),
1552                                    read_time);
1553                 if (ret)
1554                         goto err;
1555
1556                 if (a->io_time[READ] != read_time) {
1557                         struct bkey_i_alloc_v4 *a_mut =
1558                                 bch2_alloc_to_v4_mut(trans, alloc_k);
1559                         ret = PTR_ERR_OR_ZERO(a_mut);
1560                         if (ret)
1561                                 goto err;
1562
1563                         a_mut->v.io_time[READ] = read_time;
1564                         ret = bch2_trans_update(trans, alloc_iter,
1565                                                 &a_mut->k_i, BTREE_TRIGGER_NORUN);
1566                         if (ret)
1567                                 goto err;
1568                 }
1569         }
1570 err:
1571 fsck_err:
1572         bch2_trans_iter_exit(trans, &lru_iter);
1573         printbuf_exit(&buf);
1574         return ret;
1575 }
1576
1577 int bch2_check_alloc_to_lru_refs(struct bch_fs *c)
1578 {
1579         struct btree_trans trans;
1580         struct btree_iter iter;
1581         struct bkey_s_c k;
1582         int ret = 0;
1583
1584         bch2_trans_init(&trans, c, 0, 0);
1585
1586         for_each_btree_key_commit(&trans, iter, BTREE_ID_alloc,
1587                         POS_MIN, BTREE_ITER_PREFETCH, k,
1588                         NULL, NULL, BTREE_INSERT_NOFAIL|BTREE_INSERT_LAZY_RW,
1589                 bch2_check_alloc_to_lru_ref(&trans, &iter));
1590
1591         bch2_trans_exit(&trans);
1592         return ret < 0 ? ret : 0;
1593 }
1594
1595 static int bch2_discard_one_bucket(struct btree_trans *trans,
1596                                    struct btree_iter *need_discard_iter,
1597                                    struct bpos *discard_pos_done,
1598                                    u64 *seen,
1599                                    u64 *open,
1600                                    u64 *need_journal_commit,
1601                                    u64 *discarded)
1602 {
1603         struct bch_fs *c = trans->c;
1604         struct bpos pos = need_discard_iter->pos;
1605         struct btree_iter iter = { NULL };
1606         struct bkey_s_c k;
1607         struct bch_dev *ca;
1608         struct bkey_i_alloc_v4 *a;
1609         struct printbuf buf = PRINTBUF;
1610         bool did_discard = false;
1611         int ret = 0;
1612
1613         ca = bch_dev_bkey_exists(c, pos.inode);
1614         if (!percpu_ref_tryget(&ca->io_ref)) {
1615                 bch2_btree_iter_set_pos(need_discard_iter, POS(pos.inode + 1, 0));
1616                 return 0;
1617         }
1618
1619         if (bch2_bucket_is_open_safe(c, pos.inode, pos.offset)) {
1620                 (*open)++;
1621                 goto out;
1622         }
1623
1624         if (bch2_bucket_needs_journal_commit(&c->buckets_waiting_for_journal,
1625                         c->journal.flushed_seq_ondisk,
1626                         pos.inode, pos.offset)) {
1627                 (*need_journal_commit)++;
1628                 goto out;
1629         }
1630
1631         bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc,
1632                              need_discard_iter->pos,
1633                              BTREE_ITER_CACHED);
1634         k = bch2_btree_iter_peek_slot(&iter);
1635         ret = bkey_err(k);
1636         if (ret)
1637                 goto out;
1638
1639         a = bch2_alloc_to_v4_mut(trans, k);
1640         ret = PTR_ERR_OR_ZERO(a);
1641         if (ret)
1642                 goto out;
1643
1644         if (BCH_ALLOC_V4_NEED_INC_GEN(&a->v)) {
1645                 a->v.gen++;
1646                 SET_BCH_ALLOC_V4_NEED_INC_GEN(&a->v, false);
1647                 goto write;
1648         }
1649
1650         if (a->v.journal_seq > c->journal.flushed_seq_ondisk) {
1651                 if (test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
1652                         bch2_trans_inconsistent(trans,
1653                                 "clearing need_discard but journal_seq %llu > flushed_seq %llu\n"
1654                                 "%s",
1655                                 a->v.journal_seq,
1656                                 c->journal.flushed_seq_ondisk,
1657                                 (bch2_bkey_val_to_text(&buf, c, k), buf.buf));
1658                         ret = -EIO;
1659                 }
1660                 goto out;
1661         }
1662
1663         if (a->v.data_type != BCH_DATA_need_discard) {
1664                 if (test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
1665                         bch2_trans_inconsistent(trans,
1666                                 "bucket incorrectly set in need_discard btree\n"
1667                                 "%s",
1668                                 (bch2_bkey_val_to_text(&buf, c, k), buf.buf));
1669                         ret = -EIO;
1670                 }
1671
1672                 goto out;
1673         }
1674
1675         if (!bkey_eq(*discard_pos_done, iter.pos) &&
1676             ca->mi.discard && !c->opts.nochanges) {
1677                 /*
1678                  * This works without any other locks because this is the only
1679                  * thread that removes items from the need_discard tree
1680                  */
1681                 bch2_trans_unlock(trans);
1682                 blkdev_issue_discard(ca->disk_sb.bdev,
1683                                      k.k->p.offset * ca->mi.bucket_size,
1684                                      ca->mi.bucket_size,
1685                                      GFP_KERNEL);
1686
1687                 ret = bch2_trans_relock(trans);
1688                 if (ret)
1689                         goto out;
1690         }
1691
1692         *discard_pos_done = iter.pos;
1693         did_discard = true;
1694
1695         SET_BCH_ALLOC_V4_NEED_DISCARD(&a->v, false);
1696         a->v.data_type = alloc_data_type(a->v, a->v.data_type);
1697 write:
1698         ret =   bch2_trans_update(trans, &iter, &a->k_i, 0) ?:
1699                 bch2_trans_commit(trans, NULL, NULL,
1700                                   BTREE_INSERT_USE_RESERVE|BTREE_INSERT_NOFAIL);
1701         if (ret)
1702                 goto out;
1703
1704         if (did_discard) {
1705                 this_cpu_inc(c->counters[BCH_COUNTER_bucket_discard]);
1706                 (*discarded)++;
1707         }
1708 out:
1709         bch2_trans_iter_exit(trans, &iter);
1710         percpu_ref_put(&ca->io_ref);
1711         printbuf_exit(&buf);
1712         return ret;
1713 }
1714
1715 static void bch2_do_discards_work(struct work_struct *work)
1716 {
1717         struct bch_fs *c = container_of(work, struct bch_fs, discard_work);
1718         struct btree_trans trans;
1719         struct btree_iter iter;
1720         struct bkey_s_c k;
1721         u64 seen = 0, open = 0, need_journal_commit = 0, discarded = 0;
1722         struct bpos discard_pos_done = POS_MAX;
1723         int ret;
1724
1725         bch2_trans_init(&trans, c, 0, 0);
1726
1727         /*
1728          * We're doing the commit in bch2_discard_one_bucket instead of using
1729          * for_each_btree_key_commit() so that we can increment counters after
1730          * successful commit:
1731          */
1732         ret = for_each_btree_key2(&trans, iter,
1733                         BTREE_ID_need_discard, POS_MIN, 0, k,
1734                 bch2_discard_one_bucket(&trans, &iter, &discard_pos_done,
1735                                         &seen,
1736                                         &open,
1737                                         &need_journal_commit,
1738                                         &discarded));
1739
1740         bch2_trans_exit(&trans);
1741
1742         if (need_journal_commit * 2 > seen)
1743                 bch2_journal_flush_async(&c->journal, NULL);
1744
1745         percpu_ref_put(&c->writes);
1746
1747         trace_discard_buckets(c, seen, open, need_journal_commit, discarded,
1748                               bch2_err_str(ret));
1749 }
1750
1751 void bch2_do_discards(struct bch_fs *c)
1752 {
1753         if (percpu_ref_tryget_live(&c->writes) &&
1754             !queue_work(system_long_wq, &c->discard_work))
1755                 percpu_ref_put(&c->writes);
1756 }
1757
1758 static int invalidate_one_bucket(struct btree_trans *trans,
1759                                  struct btree_iter *lru_iter,
1760                                  struct bpos bucket,
1761                                  s64 *nr_to_invalidate)
1762 {
1763         struct bch_fs *c = trans->c;
1764         struct btree_iter alloc_iter = { NULL };
1765         struct bkey_i_alloc_v4 *a;
1766         struct printbuf buf = PRINTBUF;
1767         unsigned cached_sectors;
1768         int ret = 0;
1769
1770         if (*nr_to_invalidate <= 0)
1771                 return 1;
1772
1773         a = bch2_trans_start_alloc_update(trans, &alloc_iter, bucket);
1774         ret = PTR_ERR_OR_ZERO(a);
1775         if (ret)
1776                 goto out;
1777
1778         if (lru_pos_time(lru_iter->pos) != alloc_lru_idx(a->v)) {
1779                 prt_printf(&buf, "alloc key does not point back to lru entry when invalidating bucket:\n  ");
1780                 bch2_bpos_to_text(&buf, lru_iter->pos);
1781                 prt_printf(&buf, "\n  ");
1782                 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&a->k_i));
1783
1784                 bch_err(c, "%s", buf.buf);
1785                 if (test_bit(BCH_FS_CHECK_LRUS_DONE, &c->flags)) {
1786                         bch2_inconsistent_error(c);
1787                         ret = -EINVAL;
1788                 }
1789
1790                 goto out;
1791         }
1792
1793         if (!a->v.cached_sectors)
1794                 bch_err(c, "invalidating empty bucket, confused");
1795
1796         cached_sectors = a->v.cached_sectors;
1797
1798         SET_BCH_ALLOC_V4_NEED_INC_GEN(&a->v, false);
1799         a->v.gen++;
1800         a->v.data_type          = 0;
1801         a->v.dirty_sectors      = 0;
1802         a->v.cached_sectors     = 0;
1803         a->v.io_time[READ]      = atomic64_read(&c->io_clock[READ].now);
1804         a->v.io_time[WRITE]     = atomic64_read(&c->io_clock[WRITE].now);
1805
1806         ret =   bch2_trans_update(trans, &alloc_iter, &a->k_i,
1807                                 BTREE_TRIGGER_BUCKET_INVALIDATE) ?:
1808                 bch2_trans_commit(trans, NULL, NULL,
1809                                   BTREE_INSERT_USE_RESERVE|BTREE_INSERT_NOFAIL);
1810         if (ret)
1811                 goto out;
1812
1813         trace_and_count(c, bucket_invalidate, c, bucket.inode, bucket.offset, cached_sectors);
1814         --*nr_to_invalidate;
1815 out:
1816         bch2_trans_iter_exit(trans, &alloc_iter);
1817         printbuf_exit(&buf);
1818         return ret;
1819 }
1820
1821 static void bch2_do_invalidates_work(struct work_struct *work)
1822 {
1823         struct bch_fs *c = container_of(work, struct bch_fs, invalidate_work);
1824         struct bch_dev *ca;
1825         struct btree_trans trans;
1826         struct btree_iter iter;
1827         struct bkey_s_c k;
1828         unsigned i;
1829         int ret = 0;
1830
1831         bch2_trans_init(&trans, c, 0, 0);
1832
1833         for_each_member_device(ca, c, i) {
1834                 s64 nr_to_invalidate =
1835                         should_invalidate_buckets(ca, bch2_dev_usage_read(ca));
1836
1837                 ret = for_each_btree_key2_upto(&trans, iter, BTREE_ID_lru,
1838                                 lru_pos(ca->dev_idx, 0, 0),
1839                                 lru_pos(ca->dev_idx, U64_MAX, LRU_TIME_MAX),
1840                                 BTREE_ITER_INTENT, k,
1841                         invalidate_one_bucket(&trans, &iter,
1842                                               u64_to_bucket(k.k->p.offset),
1843                                               &nr_to_invalidate));
1844
1845                 if (ret < 0) {
1846                         percpu_ref_put(&ca->ref);
1847                         break;
1848                 }
1849         }
1850
1851         bch2_trans_exit(&trans);
1852         percpu_ref_put(&c->writes);
1853 }
1854
1855 void bch2_do_invalidates(struct bch_fs *c)
1856 {
1857         if (percpu_ref_tryget_live(&c->writes) &&
1858             !queue_work(system_long_wq, &c->invalidate_work))
1859                 percpu_ref_put(&c->writes);
1860 }
1861
1862 static int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca)
1863 {
1864         struct btree_trans trans;
1865         struct btree_iter iter;
1866         struct bkey_s_c k;
1867         struct bkey hole;
1868         struct bpos end = POS(ca->dev_idx, ca->mi.nbuckets);
1869         struct bch_member *m;
1870         int ret;
1871
1872         bch2_trans_init(&trans, c, 0, 0);
1873
1874         bch2_trans_iter_init(&trans, &iter, BTREE_ID_alloc,
1875                              POS(ca->dev_idx, ca->mi.first_bucket),
1876                              BTREE_ITER_PREFETCH);
1877         /*
1878          * Scan the alloc btree for every bucket on @ca, and add buckets to the
1879          * freespace/need_discard/need_gc_gens btrees as needed:
1880          */
1881         while (1) {
1882                 bch2_trans_begin(&trans);
1883
1884                 if (bkey_ge(iter.pos, end)) {
1885                         ret = 0;
1886                         break;
1887                 }
1888
1889                 k = bch2_get_key_or_hole(&iter, end, &hole);
1890                 ret = bkey_err(k);
1891                 if (ret)
1892                         goto bkey_err;
1893
1894                 if (k.k->type) {
1895                         /*
1896                          * We process live keys in the alloc btree one at a
1897                          * time:
1898                          */
1899                         struct bch_alloc_v4 a_convert;
1900                         const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, &a_convert);
1901
1902                         ret =   bch2_bucket_do_index(&trans, k, a, true) ?:
1903                                 bch2_trans_commit(&trans, NULL, NULL,
1904                                                   BTREE_INSERT_LAZY_RW|
1905                                                   BTREE_INSERT_NOFAIL);
1906                         if (ret)
1907                                 goto bkey_err;
1908
1909                         bch2_btree_iter_advance(&iter);
1910                 } else {
1911                         struct bkey_i *freespace;
1912
1913                         freespace = bch2_trans_kmalloc(&trans, sizeof(*freespace));
1914                         ret = PTR_ERR_OR_ZERO(freespace);
1915                         if (ret)
1916                                 goto bkey_err;
1917
1918                         bkey_init(&freespace->k);
1919                         freespace->k.type       = KEY_TYPE_set;
1920                         freespace->k.p          = k.k->p;
1921                         freespace->k.size       = k.k->size;
1922
1923                         ret = __bch2_btree_insert(&trans, BTREE_ID_freespace, freespace) ?:
1924                                 bch2_trans_commit(&trans, NULL, NULL,
1925                                                   BTREE_INSERT_LAZY_RW|
1926                                                   BTREE_INSERT_NOFAIL);
1927                         if (ret)
1928                                 goto bkey_err;
1929
1930                         bch2_btree_iter_set_pos(&iter, k.k->p);
1931                 }
1932 bkey_err:
1933                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
1934                         continue;
1935                 if (ret)
1936                         break;
1937         }
1938
1939         bch2_trans_iter_exit(&trans, &iter);
1940         bch2_trans_exit(&trans);
1941
1942         if (ret < 0) {
1943                 bch_err(ca, "error initializing free space: %s", bch2_err_str(ret));
1944                 return ret;
1945         }
1946
1947         mutex_lock(&c->sb_lock);
1948         m = bch2_sb_get_members(c->disk_sb.sb)->members + ca->dev_idx;
1949         SET_BCH_MEMBER_FREESPACE_INITIALIZED(m, true);
1950         mutex_unlock(&c->sb_lock);
1951
1952         return 0;
1953 }
1954
1955 int bch2_fs_freespace_init(struct bch_fs *c)
1956 {
1957         struct bch_dev *ca;
1958         unsigned i;
1959         int ret = 0;
1960         bool doing_init = false;
1961
1962         /*
1963          * We can crash during the device add path, so we need to check this on
1964          * every mount:
1965          */
1966
1967         for_each_member_device(ca, c, i) {
1968                 if (ca->mi.freespace_initialized)
1969                         continue;
1970
1971                 if (!doing_init) {
1972                         bch_info(c, "initializing freespace");
1973                         doing_init = true;
1974                 }
1975
1976                 ret = bch2_dev_freespace_init(c, ca);
1977                 if (ret) {
1978                         percpu_ref_put(&ca->ref);
1979                         return ret;
1980                 }
1981         }
1982
1983         if (doing_init) {
1984                 mutex_lock(&c->sb_lock);
1985                 bch2_write_super(c);
1986                 mutex_unlock(&c->sb_lock);
1987
1988                 bch_verbose(c, "done initializing freespace");
1989         }
1990
1991         return ret;
1992 }
1993
1994 /* Bucket IO clocks: */
1995
1996 int bch2_bucket_io_time_reset(struct btree_trans *trans, unsigned dev,
1997                               size_t bucket_nr, int rw)
1998 {
1999         struct bch_fs *c = trans->c;
2000         struct btree_iter iter;
2001         struct bkey_i_alloc_v4 *a;
2002         u64 now;
2003         int ret = 0;
2004
2005         a = bch2_trans_start_alloc_update(trans, &iter,  POS(dev, bucket_nr));
2006         ret = PTR_ERR_OR_ZERO(a);
2007         if (ret)
2008                 return ret;
2009
2010         now = atomic64_read(&c->io_clock[rw].now);
2011         if (a->v.io_time[rw] == now)
2012                 goto out;
2013
2014         a->v.io_time[rw] = now;
2015
2016         ret   = bch2_trans_update(trans, &iter, &a->k_i, 0) ?:
2017                 bch2_trans_commit(trans, NULL, NULL, 0);
2018 out:
2019         bch2_trans_iter_exit(trans, &iter);
2020         return ret;
2021 }
2022
2023 /* Startup/shutdown (ro/rw): */
2024
2025 void bch2_recalc_capacity(struct bch_fs *c)
2026 {
2027         struct bch_dev *ca;
2028         u64 capacity = 0, reserved_sectors = 0, gc_reserve;
2029         unsigned bucket_size_max = 0;
2030         unsigned long ra_pages = 0;
2031         unsigned i;
2032
2033         lockdep_assert_held(&c->state_lock);
2034
2035         for_each_online_member(ca, c, i) {
2036                 struct backing_dev_info *bdi = ca->disk_sb.bdev->bd_disk->bdi;
2037
2038                 ra_pages += bdi->ra_pages;
2039         }
2040
2041         bch2_set_ra_pages(c, ra_pages);
2042
2043         for_each_rw_member(ca, c, i) {
2044                 u64 dev_reserve = 0;
2045
2046                 /*
2047                  * We need to reserve buckets (from the number
2048                  * of currently available buckets) against
2049                  * foreground writes so that mainly copygc can
2050                  * make forward progress.
2051                  *
2052                  * We need enough to refill the various reserves
2053                  * from scratch - copygc will use its entire
2054                  * reserve all at once, then run against when
2055                  * its reserve is refilled (from the formerly
2056                  * available buckets).
2057                  *
2058                  * This reserve is just used when considering if
2059                  * allocations for foreground writes must wait -
2060                  * not -ENOSPC calculations.
2061                  */
2062
2063                 dev_reserve += ca->nr_btree_reserve * 2;
2064                 dev_reserve += ca->mi.nbuckets >> 6; /* copygc reserve */
2065
2066                 dev_reserve += 1;       /* btree write point */
2067                 dev_reserve += 1;       /* copygc write point */
2068                 dev_reserve += 1;       /* rebalance write point */
2069
2070                 dev_reserve *= ca->mi.bucket_size;
2071
2072                 capacity += bucket_to_sector(ca, ca->mi.nbuckets -
2073                                              ca->mi.first_bucket);
2074
2075                 reserved_sectors += dev_reserve * 2;
2076
2077                 bucket_size_max = max_t(unsigned, bucket_size_max,
2078                                         ca->mi.bucket_size);
2079         }
2080
2081         gc_reserve = c->opts.gc_reserve_bytes
2082                 ? c->opts.gc_reserve_bytes >> 9
2083                 : div64_u64(capacity * c->opts.gc_reserve_percent, 100);
2084
2085         reserved_sectors = max(gc_reserve, reserved_sectors);
2086
2087         reserved_sectors = min(reserved_sectors, capacity);
2088
2089         c->capacity = capacity - reserved_sectors;
2090
2091         c->bucket_size_max = bucket_size_max;
2092
2093         /* Wake up case someone was waiting for buckets */
2094         closure_wake_up(&c->freelist_wait);
2095 }
2096
2097 static bool bch2_dev_has_open_write_point(struct bch_fs *c, struct bch_dev *ca)
2098 {
2099         struct open_bucket *ob;
2100         bool ret = false;
2101
2102         for (ob = c->open_buckets;
2103              ob < c->open_buckets + ARRAY_SIZE(c->open_buckets);
2104              ob++) {
2105                 spin_lock(&ob->lock);
2106                 if (ob->valid && !ob->on_partial_list &&
2107                     ob->dev == ca->dev_idx)
2108                         ret = true;
2109                 spin_unlock(&ob->lock);
2110         }
2111
2112         return ret;
2113 }
2114
2115 /* device goes ro: */
2116 void bch2_dev_allocator_remove(struct bch_fs *c, struct bch_dev *ca)
2117 {
2118         unsigned i;
2119
2120         /* First, remove device from allocation groups: */
2121
2122         for (i = 0; i < ARRAY_SIZE(c->rw_devs); i++)
2123                 clear_bit(ca->dev_idx, c->rw_devs[i].d);
2124
2125         /*
2126          * Capacity is calculated based off of devices in allocation groups:
2127          */
2128         bch2_recalc_capacity(c);
2129
2130         /* Next, close write points that point to this device... */
2131         for (i = 0; i < ARRAY_SIZE(c->write_points); i++)
2132                 bch2_writepoint_stop(c, ca, &c->write_points[i]);
2133
2134         bch2_writepoint_stop(c, ca, &c->copygc_write_point);
2135         bch2_writepoint_stop(c, ca, &c->rebalance_write_point);
2136         bch2_writepoint_stop(c, ca, &c->btree_write_point);
2137
2138         mutex_lock(&c->btree_reserve_cache_lock);
2139         while (c->btree_reserve_cache_nr) {
2140                 struct btree_alloc *a =
2141                         &c->btree_reserve_cache[--c->btree_reserve_cache_nr];
2142
2143                 bch2_open_buckets_put(c, &a->ob);
2144         }
2145         mutex_unlock(&c->btree_reserve_cache_lock);
2146
2147         while (1) {
2148                 struct open_bucket *ob;
2149
2150                 spin_lock(&c->freelist_lock);
2151                 if (!ca->open_buckets_partial_nr) {
2152                         spin_unlock(&c->freelist_lock);
2153                         break;
2154                 }
2155                 ob = c->open_buckets +
2156                         ca->open_buckets_partial[--ca->open_buckets_partial_nr];
2157                 ob->on_partial_list = false;
2158                 spin_unlock(&c->freelist_lock);
2159
2160                 bch2_open_bucket_put(c, ob);
2161         }
2162
2163         bch2_ec_stop_dev(c, ca);
2164
2165         /*
2166          * Wake up threads that were blocked on allocation, so they can notice
2167          * the device can no longer be removed and the capacity has changed:
2168          */
2169         closure_wake_up(&c->freelist_wait);
2170
2171         /*
2172          * journal_res_get() can block waiting for free space in the journal -
2173          * it needs to notice there may not be devices to allocate from anymore:
2174          */
2175         wake_up(&c->journal.wait);
2176
2177         /* Now wait for any in flight writes: */
2178
2179         closure_wait_event(&c->open_buckets_wait,
2180                            !bch2_dev_has_open_write_point(c, ca));
2181 }
2182
2183 /* device goes rw: */
2184 void bch2_dev_allocator_add(struct bch_fs *c, struct bch_dev *ca)
2185 {
2186         unsigned i;
2187
2188         for (i = 0; i < ARRAY_SIZE(c->rw_devs); i++)
2189                 if (ca->mi.data_allowed & (1 << i))
2190                         set_bit(ca->dev_idx, c->rw_devs[i].d);
2191 }
2192
2193 void bch2_fs_allocator_background_init(struct bch_fs *c)
2194 {
2195         spin_lock_init(&c->freelist_lock);
2196         INIT_WORK(&c->discard_work, bch2_do_discards_work);
2197         INIT_WORK(&c->invalidate_work, bch2_do_invalidates_work);
2198 }