fs/bcachefs/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 "btree_write_buffer.h"
  13 #include "buckets.h"
  14 #include "buckets_waiting_for_journal.h"
  15 #include "clock.h"
  16 #include "debug.h"
  17 #include "ec.h"
  18 #include "error.h"
  19 #include "lru.h"
  20 #include "recovery.h"
  21 #include "trace.h"
  22 #include "varint.h"
  23
  24 #include <linux/kthread.h>
  25 #include <linux/math64.h>
  26 #include <linux/random.h>
  27 #include <linux/rculist.h>
  28 #include <linux/rcupdate.h>
  29 #include <linux/sched/task.h>
  30 #include <linux/sort.h>
  31
  32 static void bch2_discard_one_bucket_fast(struct bch_fs *c, struct bpos bucket);
  33
  34 /* Persistent alloc info: */
  35
  36 static const unsigned BCH_ALLOC_V1_FIELD_BYTES[] = {
  37 #define x(name, bits) [BCH_ALLOC_FIELD_V1_##name] = bits / 8,
  38         BCH_ALLOC_FIELDS_V1()
  39 #undef x
  40 };
  41
  42 struct bkey_alloc_unpacked {
  43         u64             journal_seq;
  44         u8              gen;
  45         u8              oldest_gen;
  46         u8              data_type;
  47         bool            need_discard:1;
  48         bool            need_inc_gen:1;
  49 #define x(_name, _bits) u##_bits _name;
  50         BCH_ALLOC_FIELDS_V2()
  51 #undef  x
  52 };
  53
  54 static inline u64 alloc_field_v1_get(const struct bch_alloc *a,
  55                                      const void **p, unsigned field)
  56 {
  57         unsigned bytes = BCH_ALLOC_V1_FIELD_BYTES[field];
  58         u64 v;
  59
  60         if (!(a->fields & (1 << field)))
  61                 return 0;
  62
  63         switch (bytes) {
  64         case 1:
  65                 v = *((const u8 *) *p);
  66                 break;
  67         case 2:
  68                 v = le16_to_cpup(*p);
  69                 break;
  70         case 4:
  71                 v = le32_to_cpup(*p);
  72                 break;
  73         case 8:
  74                 v = le64_to_cpup(*p);
  75                 break;
  76         default:
  77                 BUG();
  78         }
  79
  80         *p += bytes;
  81         return v;
  82 }
  83
  84 static void bch2_alloc_unpack_v1(struct bkey_alloc_unpacked *out,
  85                                  struct bkey_s_c k)
  86 {
  87         const struct bch_alloc *in = bkey_s_c_to_alloc(k).v;
  88         const void *d = in->data;
  89         unsigned idx = 0;
  90
  91         out->gen = in->gen;
  92
  93 #define x(_name, _bits) out->_name = alloc_field_v1_get(in, &d, idx++);
  94         BCH_ALLOC_FIELDS_V1()
  95 #undef  x
  96 }
  97
  98 static int bch2_alloc_unpack_v2(struct bkey_alloc_unpacked *out,
  99                                 struct bkey_s_c k)
 100 {
 101         struct bkey_s_c_alloc_v2 a = bkey_s_c_to_alloc_v2(k);
 102         const u8 *in = a.v->data;
 103         const u8 *end = bkey_val_end(a);
 104         unsigned fieldnr = 0;
 105         int ret;
 106         u64 v;
 107
 108         out->gen        = a.v->gen;
 109         out->oldest_gen = a.v->oldest_gen;
 110         out->data_type  = a.v->data_type;
 111
 112 #define x(_name, _bits)                                                 \
 113         if (fieldnr < a.v->nr_fields) {                                 \
 114                 ret = bch2_varint_decode_fast(in, end, &v);             \
 115                 if (ret < 0)                                            \
 116                         return ret;                                     \
 117                 in += ret;                                              \
 118         } else {                                                        \
 119                 v = 0;                                                  \
 120         }                                                               \
 121         out->_name = v;                                                 \
 122         if (v != out->_name)                                            \
 123                 return -1;                                              \
 124         fieldnr++;
 125
 126         BCH_ALLOC_FIELDS_V2()
 127 #undef  x
 128         return 0;
 129 }
 130
 131 static int bch2_alloc_unpack_v3(struct bkey_alloc_unpacked *out,
 132                                 struct bkey_s_c k)
 133 {
 134         struct bkey_s_c_alloc_v3 a = bkey_s_c_to_alloc_v3(k);
 135         const u8 *in = a.v->data;
 136         const u8 *end = bkey_val_end(a);
 137         unsigned fieldnr = 0;
 138         int ret;
 139         u64 v;
 140
 141         out->gen        = a.v->gen;
 142         out->oldest_gen = a.v->oldest_gen;
 143         out->data_type  = a.v->data_type;
 144         out->need_discard = BCH_ALLOC_V3_NEED_DISCARD(a.v);
 145         out->need_inc_gen = BCH_ALLOC_V3_NEED_INC_GEN(a.v);
 146         out->journal_seq = le64_to_cpu(a.v->journal_seq);
 147
 148 #define x(_name, _bits)                                                 \
 149         if (fieldnr < a.v->nr_fields) {                                 \
 150                 ret = bch2_varint_decode_fast(in, end, &v);             \
 151                 if (ret < 0)                                            \
 152                         return ret;                                     \
 153                 in += ret;                                              \
 154         } else {                                                        \
 155                 v = 0;                                                  \
 156         }                                                               \
 157         out->_name = v;                                                 \
 158         if (v != out->_name)                                            \
 159                 return -1;                                              \
 160         fieldnr++;
 161
 162         BCH_ALLOC_FIELDS_V2()
 163 #undef  x
 164         return 0;
 165 }
 166
 167 static struct bkey_alloc_unpacked bch2_alloc_unpack(struct bkey_s_c k)
 168 {
 169         struct bkey_alloc_unpacked ret = { .gen = 0 };
 170
 171         switch (k.k->type) {
 172         case KEY_TYPE_alloc:
 173                 bch2_alloc_unpack_v1(&ret, k);
 174                 break;
 175         case KEY_TYPE_alloc_v2:
 176                 bch2_alloc_unpack_v2(&ret, k);
 177                 break;
 178         case KEY_TYPE_alloc_v3:
 179                 bch2_alloc_unpack_v3(&ret, k);
 180                 break;
 181         }
 182
 183         return ret;
 184 }
 185
 186 static unsigned bch_alloc_v1_val_u64s(const struct bch_alloc *a)
 187 {
 188         unsigned i, bytes = offsetof(struct bch_alloc, data);
 189
 190         for (i = 0; i < ARRAY_SIZE(BCH_ALLOC_V1_FIELD_BYTES); i++)
 191                 if (a->fields & (1 << i))
 192                         bytes += BCH_ALLOC_V1_FIELD_BYTES[i];
 193
 194         return DIV_ROUND_UP(bytes, sizeof(u64));
 195 }
 196
 197 int bch2_alloc_v1_invalid(struct bch_fs *c, struct bkey_s_c k,
 198                           enum bkey_invalid_flags flags,
 199                           struct printbuf *err)
 200 {
 201         struct bkey_s_c_alloc a = bkey_s_c_to_alloc(k);
 202         int ret = 0;
 203
 204         /* allow for unknown fields */
 205         bkey_fsck_err_on(bkey_val_u64s(a.k) < bch_alloc_v1_val_u64s(a.v), c, err,
 206                          alloc_v1_val_size_bad,
 207                          "incorrect value size (%zu < %u)",
 208                          bkey_val_u64s(a.k), bch_alloc_v1_val_u64s(a.v));
 209 fsck_err:
 210         return ret;
 211 }
 212
 213 int bch2_alloc_v2_invalid(struct bch_fs *c, struct bkey_s_c k,
 214                           enum bkey_invalid_flags flags,
 215                           struct printbuf *err)
 216 {
 217         struct bkey_alloc_unpacked u;
 218         int ret = 0;
 219
 220         bkey_fsck_err_on(bch2_alloc_unpack_v2(&u, k), c, err,
 221                          alloc_v2_unpack_error,
 222                          "unpack error");
 223 fsck_err:
 224         return ret;
 225 }
 226
 227 int bch2_alloc_v3_invalid(struct bch_fs *c, struct bkey_s_c k,
 228                           enum bkey_invalid_flags flags,
 229                           struct printbuf *err)
 230 {
 231         struct bkey_alloc_unpacked u;
 232         int ret = 0;
 233
 234         bkey_fsck_err_on(bch2_alloc_unpack_v3(&u, k), c, err,
 235                          alloc_v2_unpack_error,
 236                          "unpack error");
 237 fsck_err:
 238         return ret;
 239 }
 240
 241 int bch2_alloc_v4_invalid(struct bch_fs *c, struct bkey_s_c k,
 242                           enum bkey_invalid_flags flags, struct printbuf *err)
 243 {
 244         struct bkey_s_c_alloc_v4 a = bkey_s_c_to_alloc_v4(k);
 245         int ret = 0;
 246
 247         bkey_fsck_err_on(alloc_v4_u64s_noerror(a.v) > bkey_val_u64s(k.k), c, err,
 248                          alloc_v4_val_size_bad,
 249                          "bad val size (%u > %zu)",
 250                          alloc_v4_u64s_noerror(a.v), bkey_val_u64s(k.k));
 251
 252         bkey_fsck_err_on(!BCH_ALLOC_V4_BACKPOINTERS_START(a.v) &&
 253                          BCH_ALLOC_V4_NR_BACKPOINTERS(a.v), c, err,
 254                          alloc_v4_backpointers_start_bad,
 255                          "invalid backpointers_start");
 256
 257         bkey_fsck_err_on(alloc_data_type(*a.v, a.v->data_type) != a.v->data_type, c, err,
 258                          alloc_key_data_type_bad,
 259                          "invalid data type (got %u should be %u)",
 260                          a.v->data_type, alloc_data_type(*a.v, a.v->data_type));
 261
 262         switch (a.v->data_type) {
 263         case BCH_DATA_free:
 264         case BCH_DATA_need_gc_gens:
 265         case BCH_DATA_need_discard:
 266                 bkey_fsck_err_on(bch2_bucket_sectors(*a.v) || a.v->stripe,
 267                                  c, err, alloc_key_empty_but_have_data,
 268                                  "empty data type free but have data");
 269                 break;
 270         case BCH_DATA_sb:
 271         case BCH_DATA_journal:
 272         case BCH_DATA_btree:
 273         case BCH_DATA_user:
 274         case BCH_DATA_parity:
 275                 bkey_fsck_err_on(!bch2_bucket_sectors_dirty(*a.v),
 276                                  c, err, alloc_key_dirty_sectors_0,
 277                                  "data_type %s but dirty_sectors==0",
 278                                  bch2_data_type_str(a.v->data_type));
 279                 break;
 280         case BCH_DATA_cached:
 281                 bkey_fsck_err_on(!a.v->cached_sectors ||
 282                                  bch2_bucket_sectors_dirty(*a.v) ||
 283                                  a.v->stripe,
 284                                  c, err, alloc_key_cached_inconsistency,
 285                                  "data type inconsistency");
 286
 287                 bkey_fsck_err_on(!a.v->io_time[READ] &&
 288                                  c->curr_recovery_pass > BCH_RECOVERY_PASS_check_alloc_to_lru_refs,
 289                                  c, err, alloc_key_cached_but_read_time_zero,
 290                                  "cached bucket with read_time == 0");
 291                 break;
 292         case BCH_DATA_stripe:
 293                 break;
 294         }
 295 fsck_err:
 296         return ret;
 297 }
 298
 299 void bch2_alloc_v4_swab(struct bkey_s k)
 300 {
 301         struct bch_alloc_v4 *a = bkey_s_to_alloc_v4(k).v;
 302         struct bch_backpointer *bp, *bps;
 303
 304         a->journal_seq          = swab64(a->journal_seq);
 305         a->flags                = swab32(a->flags);
 306         a->dirty_sectors        = swab32(a->dirty_sectors);
 307         a->cached_sectors       = swab32(a->cached_sectors);
 308         a->io_time[0]           = swab64(a->io_time[0]);
 309         a->io_time[1]           = swab64(a->io_time[1]);
 310         a->stripe               = swab32(a->stripe);
 311         a->nr_external_backpointers = swab32(a->nr_external_backpointers);
 312         a->fragmentation_lru    = swab64(a->fragmentation_lru);
 313
 314         bps = alloc_v4_backpointers(a);
 315         for (bp = bps; bp < bps + BCH_ALLOC_V4_NR_BACKPOINTERS(a); bp++) {
 316                 bp->bucket_offset       = swab40(bp->bucket_offset);
 317                 bp->bucket_len          = swab32(bp->bucket_len);
 318                 bch2_bpos_swab(&bp->pos);
 319         }
 320 }
 321
 322 void bch2_alloc_to_text(struct printbuf *out, struct bch_fs *c, struct bkey_s_c k)
 323 {
 324         struct bch_alloc_v4 _a;
 325         const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, &_a);
 326
 327         prt_newline(out);
 328         printbuf_indent_add(out, 2);
 329
 330         prt_printf(out, "gen %u oldest_gen %u data_type ", a->gen, a->oldest_gen);
 331         bch2_prt_data_type(out, a->data_type);
 332         prt_newline(out);
 333         prt_printf(out, "journal_seq       %llu",       a->journal_seq);
 334         prt_newline(out);
 335         prt_printf(out, "need_discard      %llu",       BCH_ALLOC_V4_NEED_DISCARD(a));
 336         prt_newline(out);
 337         prt_printf(out, "need_inc_gen      %llu",       BCH_ALLOC_V4_NEED_INC_GEN(a));
 338         prt_newline(out);
 339         prt_printf(out, "dirty_sectors     %u", a->dirty_sectors);
 340         prt_newline(out);
 341         prt_printf(out, "cached_sectors    %u", a->cached_sectors);
 342         prt_newline(out);
 343         prt_printf(out, "stripe            %u", a->stripe);
 344         prt_newline(out);
 345         prt_printf(out, "stripe_redundancy %u", a->stripe_redundancy);
 346         prt_newline(out);
 347         prt_printf(out, "io_time[READ]     %llu",       a->io_time[READ]);
 348         prt_newline(out);
 349         prt_printf(out, "io_time[WRITE]    %llu",       a->io_time[WRITE]);
 350         prt_newline(out);
 351         prt_printf(out, "fragmentation     %llu",       a->fragmentation_lru);
 352         prt_newline(out);
 353         prt_printf(out, "bp_start          %llu", BCH_ALLOC_V4_BACKPOINTERS_START(a));
 354         printbuf_indent_sub(out, 2);
 355 }
 356
 357 void __bch2_alloc_to_v4(struct bkey_s_c k, struct bch_alloc_v4 *out)
 358 {
 359         if (k.k->type == KEY_TYPE_alloc_v4) {
 360                 void *src, *dst;
 361
 362                 *out = *bkey_s_c_to_alloc_v4(k).v;
 363
 364                 src = alloc_v4_backpointers(out);
 365                 SET_BCH_ALLOC_V4_BACKPOINTERS_START(out, BCH_ALLOC_V4_U64s);
 366                 dst = alloc_v4_backpointers(out);
 367
 368                 if (src < dst)
 369                         memset(src, 0, dst - src);
 370
 371                 SET_BCH_ALLOC_V4_NR_BACKPOINTERS(out, 0);
 372         } else {
 373                 struct bkey_alloc_unpacked u = bch2_alloc_unpack(k);
 374
 375                 *out = (struct bch_alloc_v4) {
 376                         .journal_seq            = u.journal_seq,
 377                         .flags                  = u.need_discard,
 378                         .gen                    = u.gen,
 379                         .oldest_gen             = u.oldest_gen,
 380                         .data_type              = u.data_type,
 381                         .stripe_redundancy      = u.stripe_redundancy,
 382                         .dirty_sectors          = u.dirty_sectors,
 383                         .cached_sectors         = u.cached_sectors,
 384                         .io_time[READ]          = u.read_time,
 385                         .io_time[WRITE]         = u.write_time,
 386                         .stripe                 = u.stripe,
 387                 };
 388
 389                 SET_BCH_ALLOC_V4_BACKPOINTERS_START(out, BCH_ALLOC_V4_U64s);
 390         }
 391 }
 392
 393 static noinline struct bkey_i_alloc_v4 *
 394 __bch2_alloc_to_v4_mut(struct btree_trans *trans, struct bkey_s_c k)
 395 {
 396         struct bkey_i_alloc_v4 *ret;
 397
 398         ret = bch2_trans_kmalloc(trans, max(bkey_bytes(k.k), sizeof(struct bkey_i_alloc_v4)));
 399         if (IS_ERR(ret))
 400                 return ret;
 401
 402         if (k.k->type == KEY_TYPE_alloc_v4) {
 403                 void *src, *dst;
 404
 405                 bkey_reassemble(&ret->k_i, k);
 406
 407                 src = alloc_v4_backpointers(&ret->v);
 408                 SET_BCH_ALLOC_V4_BACKPOINTERS_START(&ret->v, BCH_ALLOC_V4_U64s);
 409                 dst = alloc_v4_backpointers(&ret->v);
 410
 411                 if (src < dst)
 412                         memset(src, 0, dst - src);
 413
 414                 SET_BCH_ALLOC_V4_NR_BACKPOINTERS(&ret->v, 0);
 415                 set_alloc_v4_u64s(ret);
 416         } else {
 417                 bkey_alloc_v4_init(&ret->k_i);
 418                 ret->k.p = k.k->p;
 419                 bch2_alloc_to_v4(k, &ret->v);
 420         }
 421         return ret;
 422 }
 423
 424 static inline struct bkey_i_alloc_v4 *bch2_alloc_to_v4_mut_inlined(struct btree_trans *trans, struct bkey_s_c k)
 425 {
 426         struct bkey_s_c_alloc_v4 a;
 427
 428         if (likely(k.k->type == KEY_TYPE_alloc_v4) &&
 429             ((a = bkey_s_c_to_alloc_v4(k), true) &&
 430              BCH_ALLOC_V4_NR_BACKPOINTERS(a.v) == 0))
 431                 return bch2_bkey_make_mut_noupdate_typed(trans, k, alloc_v4);
 432
 433         return __bch2_alloc_to_v4_mut(trans, k);
 434 }
 435
 436 struct bkey_i_alloc_v4 *bch2_alloc_to_v4_mut(struct btree_trans *trans, struct bkey_s_c k)
 437 {
 438         return bch2_alloc_to_v4_mut_inlined(trans, k);
 439 }
 440
 441 struct bkey_i_alloc_v4 *
 442 bch2_trans_start_alloc_update(struct btree_trans *trans, struct btree_iter *iter,
 443                               struct bpos pos)
 444 {
 445         struct bkey_s_c k;
 446         struct bkey_i_alloc_v4 *a;
 447         int ret;
 448
 449         k = bch2_bkey_get_iter(trans, iter, BTREE_ID_alloc, pos,
 450                              BTREE_ITER_WITH_UPDATES|
 451                              BTREE_ITER_CACHED|
 452                              BTREE_ITER_INTENT);
 453         ret = bkey_err(k);
 454         if (unlikely(ret))
 455                 return ERR_PTR(ret);
 456
 457         a = bch2_alloc_to_v4_mut_inlined(trans, k);
 458         ret = PTR_ERR_OR_ZERO(a);
 459         if (unlikely(ret))
 460                 goto err;
 461         return a;
 462 err:
 463         bch2_trans_iter_exit(trans, iter);
 464         return ERR_PTR(ret);
 465 }
 466
 467 static struct bpos alloc_gens_pos(struct bpos pos, unsigned *offset)
 468 {
 469         *offset = pos.offset & KEY_TYPE_BUCKET_GENS_MASK;
 470
 471         pos.offset >>= KEY_TYPE_BUCKET_GENS_BITS;
 472         return pos;
 473 }
 474
 475 static struct bpos bucket_gens_pos_to_alloc(struct bpos pos, unsigned offset)
 476 {
 477         pos.offset <<= KEY_TYPE_BUCKET_GENS_BITS;
 478         pos.offset += offset;
 479         return pos;
 480 }
 481
 482 static unsigned alloc_gen(struct bkey_s_c k, unsigned offset)
 483 {
 484         return k.k->type == KEY_TYPE_bucket_gens
 485                 ? bkey_s_c_to_bucket_gens(k).v->gens[offset]
 486                 : 0;
 487 }
 488
 489 int bch2_bucket_gens_invalid(struct bch_fs *c, struct bkey_s_c k,
 490                              enum bkey_invalid_flags flags,
 491                              struct printbuf *err)
 492 {
 493         int ret = 0;
 494
 495         bkey_fsck_err_on(bkey_val_bytes(k.k) != sizeof(struct bch_bucket_gens), c, err,
 496                          bucket_gens_val_size_bad,
 497                          "bad val size (%zu != %zu)",
 498                          bkey_val_bytes(k.k), sizeof(struct bch_bucket_gens));
 499 fsck_err:
 500         return ret;
 501 }
 502
 503 void bch2_bucket_gens_to_text(struct printbuf *out, struct bch_fs *c, struct bkey_s_c k)
 504 {
 505         struct bkey_s_c_bucket_gens g = bkey_s_c_to_bucket_gens(k);
 506         unsigned i;
 507
 508         for (i = 0; i < ARRAY_SIZE(g.v->gens); i++) {
 509                 if (i)
 510                         prt_char(out, ' ');
 511                 prt_printf(out, "%u", g.v->gens[i]);
 512         }
 513 }
 514
 515 int bch2_bucket_gens_init(struct bch_fs *c)
 516 {
 517         struct btree_trans *trans = bch2_trans_get(c);
 518         struct bkey_i_bucket_gens g;
 519         bool have_bucket_gens_key = false;
 520         int ret;
 521
 522         ret = for_each_btree_key(trans, iter, BTREE_ID_alloc, POS_MIN,
 523                                  BTREE_ITER_PREFETCH, k, ({
 524                 /*
 525                  * Not a fsck error because this is checked/repaired by
 526                  * bch2_check_alloc_key() which runs later:
 527                  */
 528                 if (!bch2_dev_bucket_exists(c, k.k->p))
 529                         continue;
 530
 531                 struct bch_alloc_v4 a;
 532                 u8 gen = bch2_alloc_to_v4(k, &a)->gen;
 533                 unsigned offset;
 534                 struct bpos pos = alloc_gens_pos(iter.pos, &offset);
 535                 int ret2 = 0;
 536
 537                 if (have_bucket_gens_key && bkey_cmp(iter.pos, pos)) {
 538                         ret2 =  bch2_btree_insert_trans(trans, BTREE_ID_bucket_gens, &g.k_i, 0) ?:
 539                                 bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
 540                         if (ret2)
 541                                 goto iter_err;
 542                         have_bucket_gens_key = false;
 543                 }
 544
 545                 if (!have_bucket_gens_key) {
 546                         bkey_bucket_gens_init(&g.k_i);
 547                         g.k.p = pos;
 548                         have_bucket_gens_key = true;
 549                 }
 550
 551                 g.v.gens[offset] = gen;
 552 iter_err:
 553                 ret2;
 554         }));
 555
 556         if (have_bucket_gens_key && !ret)
 557                 ret = commit_do(trans, NULL, NULL,
 558                                 BCH_TRANS_COMMIT_no_enospc,
 559                         bch2_btree_insert_trans(trans, BTREE_ID_bucket_gens, &g.k_i, 0));
 560
 561         bch2_trans_put(trans);
 562
 563         bch_err_fn(c, ret);
 564         return ret;
 565 }
 566
 567 int bch2_alloc_read(struct bch_fs *c)
 568 {
 569         struct btree_trans *trans = bch2_trans_get(c);
 570         int ret;
 571
 572         down_read(&c->gc_lock);
 573
 574         if (c->sb.version_upgrade_complete >= bcachefs_metadata_version_bucket_gens) {
 575                 ret = for_each_btree_key(trans, iter, BTREE_ID_bucket_gens, POS_MIN,
 576                                          BTREE_ITER_PREFETCH, k, ({
 577                         u64 start = bucket_gens_pos_to_alloc(k.k->p, 0).offset;
 578                         u64 end = bucket_gens_pos_to_alloc(bpos_nosnap_successor(k.k->p), 0).offset;
 579
 580                         if (k.k->type != KEY_TYPE_bucket_gens)
 581                                 continue;
 582
 583                         const struct bch_bucket_gens *g = bkey_s_c_to_bucket_gens(k).v;
 584
 585                         /*
 586                          * Not a fsck error because this is checked/repaired by
 587                          * bch2_check_alloc_key() which runs later:
 588                          */
 589                         if (!bch2_dev_exists2(c, k.k->p.inode))
 590                                 continue;
 591
 592                         struct bch_dev *ca = bch_dev_bkey_exists(c, k.k->p.inode);
 593
 594                         for (u64 b = max_t(u64, ca->mi.first_bucket, start);
 595                              b < min_t(u64, ca->mi.nbuckets, end);
 596                              b++)
 597                                 *bucket_gen(ca, b) = g->gens[b & KEY_TYPE_BUCKET_GENS_MASK];
 598                         0;
 599                 }));
 600         } else {
 601                 ret = for_each_btree_key(trans, iter, BTREE_ID_alloc, POS_MIN,
 602                                          BTREE_ITER_PREFETCH, k, ({
 603                         /*
 604                          * Not a fsck error because this is checked/repaired by
 605                          * bch2_check_alloc_key() which runs later:
 606                          */
 607                         if (!bch2_dev_bucket_exists(c, k.k->p))
 608                                 continue;
 609
 610                         struct bch_dev *ca = bch_dev_bkey_exists(c, k.k->p.inode);
 611
 612                         struct bch_alloc_v4 a;
 613                         *bucket_gen(ca, k.k->p.offset) = bch2_alloc_to_v4(k, &a)->gen;
 614                         0;
 615                 }));
 616         }
 617
 618         bch2_trans_put(trans);
 619         up_read(&c->gc_lock);
 620
 621         bch_err_fn(c, ret);
 622         return ret;
 623 }
 624
 625 /* Free space/discard btree: */
 626
 627 static int bch2_bucket_do_index(struct btree_trans *trans,
 628                                 struct bkey_s_c alloc_k,
 629                                 const struct bch_alloc_v4 *a,
 630                                 bool set)
 631 {
 632         struct bch_fs *c = trans->c;
 633         struct bch_dev *ca = bch_dev_bkey_exists(c, alloc_k.k->p.inode);
 634         struct btree_iter iter;
 635         struct bkey_s_c old;
 636         struct bkey_i *k;
 637         enum btree_id btree;
 638         enum bch_bkey_type old_type = !set ? KEY_TYPE_set : KEY_TYPE_deleted;
 639         enum bch_bkey_type new_type =  set ? KEY_TYPE_set : KEY_TYPE_deleted;
 640         struct printbuf buf = PRINTBUF;
 641         int ret;
 642
 643         if (a->data_type != BCH_DATA_free &&
 644             a->data_type != BCH_DATA_need_discard)
 645                 return 0;
 646
 647         k = bch2_trans_kmalloc_nomemzero(trans, sizeof(*k));
 648         if (IS_ERR(k))
 649                 return PTR_ERR(k);
 650
 651         bkey_init(&k->k);
 652         k->k.type = new_type;
 653
 654         switch (a->data_type) {
 655         case BCH_DATA_free:
 656                 btree = BTREE_ID_freespace;
 657                 k->k.p = alloc_freespace_pos(alloc_k.k->p, *a);
 658                 bch2_key_resize(&k->k, 1);
 659                 break;
 660         case BCH_DATA_need_discard:
 661                 btree = BTREE_ID_need_discard;
 662                 k->k.p = alloc_k.k->p;
 663                 break;
 664         default:
 665                 return 0;
 666         }
 667
 668         old = bch2_bkey_get_iter(trans, &iter, btree,
 669                              bkey_start_pos(&k->k),
 670                              BTREE_ITER_INTENT);
 671         ret = bkey_err(old);
 672         if (ret)
 673                 return ret;
 674
 675         if (ca->mi.freespace_initialized &&
 676             c->curr_recovery_pass > BCH_RECOVERY_PASS_check_alloc_info &&
 677             bch2_trans_inconsistent_on(old.k->type != old_type, trans,
 678                         "incorrect key when %s %s:%llu:%llu:0 (got %s should be %s)\n"
 679                         "  for %s",
 680                         set ? "setting" : "clearing",
 681                         bch2_btree_id_str(btree),
 682                         iter.pos.inode,
 683                         iter.pos.offset,
 684                         bch2_bkey_types[old.k->type],
 685                         bch2_bkey_types[old_type],
 686                         (bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
 687                 ret = -EIO;
 688                 goto err;
 689         }
 690
 691         ret = bch2_trans_update(trans, &iter, k, 0);
 692 err:
 693         bch2_trans_iter_exit(trans, &iter);
 694         printbuf_exit(&buf);
 695         return ret;
 696 }
 697
 698 static noinline int bch2_bucket_gen_update(struct btree_trans *trans,
 699                                            struct bpos bucket, u8 gen)
 700 {
 701         struct btree_iter iter;
 702         unsigned offset;
 703         struct bpos pos = alloc_gens_pos(bucket, &offset);
 704         struct bkey_i_bucket_gens *g;
 705         struct bkey_s_c k;
 706         int ret;
 707
 708         g = bch2_trans_kmalloc(trans, sizeof(*g));
 709         ret = PTR_ERR_OR_ZERO(g);
 710         if (ret)
 711                 return ret;
 712
 713         k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_bucket_gens, pos,
 714                                BTREE_ITER_INTENT|
 715                                BTREE_ITER_WITH_UPDATES);
 716         ret = bkey_err(k);
 717         if (ret)
 718                 return ret;
 719
 720         if (k.k->type != KEY_TYPE_bucket_gens) {
 721                 bkey_bucket_gens_init(&g->k_i);
 722                 g->k.p = iter.pos;
 723         } else {
 724                 bkey_reassemble(&g->k_i, k);
 725         }
 726
 727         g->v.gens[offset] = gen;
 728
 729         ret = bch2_trans_update(trans, &iter, &g->k_i, 0);
 730         bch2_trans_iter_exit(trans, &iter);
 731         return ret;
 732 }
 733
 734 int bch2_trigger_alloc(struct btree_trans *trans,
 735                        enum btree_id btree, unsigned level,
 736                        struct bkey_s_c old, struct bkey_s new,
 737                        unsigned flags)
 738 {
 739         struct bch_fs *c = trans->c;
 740         int ret = 0;
 741
 742         if (bch2_trans_inconsistent_on(!bch2_dev_bucket_exists(c, new.k->p), trans,
 743                                        "alloc key for invalid device or bucket"))
 744                 return -EIO;
 745
 746         struct bch_dev *ca = bch_dev_bkey_exists(c, new.k->p.inode);
 747
 748         struct bch_alloc_v4 old_a_convert;
 749         const struct bch_alloc_v4 *old_a = bch2_alloc_to_v4(old, &old_a_convert);
 750
 751         if (flags & BTREE_TRIGGER_TRANSACTIONAL) {
 752                 struct bch_alloc_v4 *new_a = bkey_s_to_alloc_v4(new).v;
 753
 754                 new_a->data_type = alloc_data_type(*new_a, new_a->data_type);
 755
 756                 if (bch2_bucket_sectors(*new_a) > bch2_bucket_sectors(*old_a)) {
 757                         new_a->io_time[READ] = max_t(u64, 1, atomic64_read(&c->io_clock[READ].now));
 758                         new_a->io_time[WRITE]= max_t(u64, 1, atomic64_read(&c->io_clock[WRITE].now));
 759                         SET_BCH_ALLOC_V4_NEED_INC_GEN(new_a, true);
 760                         SET_BCH_ALLOC_V4_NEED_DISCARD(new_a, true);
 761                 }
 762
 763                 if (data_type_is_empty(new_a->data_type) &&
 764                     BCH_ALLOC_V4_NEED_INC_GEN(new_a) &&
 765                     !bch2_bucket_is_open_safe(c, new.k->p.inode, new.k->p.offset)) {
 766                         new_a->gen++;
 767                         SET_BCH_ALLOC_V4_NEED_INC_GEN(new_a, false);
 768                 }
 769
 770                 if (old_a->data_type != new_a->data_type ||
 771                     (new_a->data_type == BCH_DATA_free &&
 772                      alloc_freespace_genbits(*old_a) != alloc_freespace_genbits(*new_a))) {
 773                         ret =   bch2_bucket_do_index(trans, old, old_a, false) ?:
 774                                 bch2_bucket_do_index(trans, new.s_c, new_a, true);
 775                         if (ret)
 776                                 return ret;
 777                 }
 778
 779                 if (new_a->data_type == BCH_DATA_cached &&
 780                     !new_a->io_time[READ])
 781                         new_a->io_time[READ] = max_t(u64, 1, atomic64_read(&c->io_clock[READ].now));
 782
 783                 u64 old_lru = alloc_lru_idx_read(*old_a);
 784                 u64 new_lru = alloc_lru_idx_read(*new_a);
 785                 if (old_lru != new_lru) {
 786                         ret = bch2_lru_change(trans, new.k->p.inode,
 787                                               bucket_to_u64(new.k->p),
 788                                               old_lru, new_lru);
 789                         if (ret)
 790                                 return ret;
 791                 }
 792
 793                 new_a->fragmentation_lru = alloc_lru_idx_fragmentation(*new_a,
 794                                                 bch_dev_bkey_exists(c, new.k->p.inode));
 795                 if (old_a->fragmentation_lru != new_a->fragmentation_lru) {
 796                         ret = bch2_lru_change(trans,
 797                                         BCH_LRU_FRAGMENTATION_START,
 798                                         bucket_to_u64(new.k->p),
 799                                         old_a->fragmentation_lru, new_a->fragmentation_lru);
 800                         if (ret)
 801                                 return ret;
 802                 }
 803
 804                 if (old_a->gen != new_a->gen) {
 805                         ret = bch2_bucket_gen_update(trans, new.k->p, new_a->gen);
 806                         if (ret)
 807                                 return ret;
 808                 }
 809
 810                 /*
 811                  * need to know if we're getting called from the invalidate path or
 812                  * not:
 813                  */
 814
 815                 if ((flags & BTREE_TRIGGER_BUCKET_INVALIDATE) &&
 816                     old_a->cached_sectors) {
 817                         ret = bch2_update_cached_sectors_list(trans, new.k->p.inode,
 818                                                               -((s64) old_a->cached_sectors));
 819                         if (ret)
 820                                 return ret;
 821                 }
 822         }
 823
 824         if ((flags & BTREE_TRIGGER_ATOMIC) && (flags & BTREE_TRIGGER_INSERT)) {
 825                 struct bch_alloc_v4 *new_a = bkey_s_to_alloc_v4(new).v;
 826                 u64 journal_seq = trans->journal_res.seq;
 827                 u64 bucket_journal_seq = new_a->journal_seq;
 828
 829                 if ((flags & BTREE_TRIGGER_INSERT) &&
 830                     data_type_is_empty(old_a->data_type) !=
 831                     data_type_is_empty(new_a->data_type) &&
 832                     new.k->type == KEY_TYPE_alloc_v4) {
 833                         struct bch_alloc_v4 *v = bkey_s_to_alloc_v4(new).v;
 834
 835                         /*
 836                          * If the btree updates referring to a bucket weren't flushed
 837                          * before the bucket became empty again, then the we don't have
 838                          * to wait on a journal flush before we can reuse the bucket:
 839                          */
 840                         v->journal_seq = bucket_journal_seq =
 841                                 data_type_is_empty(new_a->data_type) &&
 842                                 (journal_seq == v->journal_seq ||
 843                                  bch2_journal_noflush_seq(&c->journal, v->journal_seq))
 844                                 ? 0 : journal_seq;
 845                 }
 846
 847                 if (!data_type_is_empty(old_a->data_type) &&
 848                     data_type_is_empty(new_a->data_type) &&
 849                     bucket_journal_seq) {
 850                         ret = bch2_set_bucket_needs_journal_commit(&c->buckets_waiting_for_journal,
 851                                         c->journal.flushed_seq_ondisk,
 852                                         new.k->p.inode, new.k->p.offset,
 853                                         bucket_journal_seq);
 854                         if (ret) {
 855                                 bch2_fs_fatal_error(c,
 856                                         "setting bucket_needs_journal_commit: %s", bch2_err_str(ret));
 857                                 return ret;
 858                         }
 859                 }
 860
 861                 percpu_down_read(&c->mark_lock);
 862                 if (new_a->gen != old_a->gen)
 863                         *bucket_gen(ca, new.k->p.offset) = new_a->gen;
 864
 865                 bch2_dev_usage_update(c, ca, old_a, new_a, journal_seq, false);
 866                 percpu_up_read(&c->mark_lock);
 867
 868 #define eval_state(_a, expr)            ({ const struct bch_alloc_v4 *a = _a; expr; })
 869 #define statechange(expr)               !eval_state(old_a, expr) && eval_state(new_a, expr)
 870 #define bucket_flushed(a)               (!a->journal_seq || a->journal_seq <= c->journal.flushed_seq_ondisk)
 871
 872                 if (statechange(a->data_type == BCH_DATA_free) &&
 873                     bucket_flushed(new_a))
 874                         closure_wake_up(&c->freelist_wait);
 875
 876                 if (statechange(a->data_type == BCH_DATA_need_discard) &&
 877                     !bch2_bucket_is_open(c, new.k->p.inode, new.k->p.offset) &&
 878                     bucket_flushed(new_a))
 879                         bch2_discard_one_bucket_fast(c, new.k->p);
 880
 881                 if (statechange(a->data_type == BCH_DATA_cached) &&
 882                     !bch2_bucket_is_open(c, new.k->p.inode, new.k->p.offset) &&
 883                     should_invalidate_buckets(ca, bch2_dev_usage_read(ca)))
 884                         bch2_do_invalidates(c);
 885
 886                 if (statechange(a->data_type == BCH_DATA_need_gc_gens))
 887                         bch2_do_gc_gens(c);
 888         }
 889
 890         if ((flags & BTREE_TRIGGER_GC) &&
 891             (flags & BTREE_TRIGGER_BUCKET_INVALIDATE)) {
 892                 struct bch_alloc_v4 new_a_convert;
 893                 const struct bch_alloc_v4 *new_a = bch2_alloc_to_v4(new.s_c, &new_a_convert);
 894
 895                 percpu_down_read(&c->mark_lock);
 896                 struct bucket *g = gc_bucket(ca, new.k->p.offset);
 897
 898                 bucket_lock(g);
 899
 900                 g->gen_valid            = 1;
 901                 g->gen                  = new_a->gen;
 902                 g->data_type            = new_a->data_type;
 903                 g->stripe               = new_a->stripe;
 904                 g->stripe_redundancy    = new_a->stripe_redundancy;
 905                 g->dirty_sectors        = new_a->dirty_sectors;
 906                 g->cached_sectors       = new_a->cached_sectors;
 907
 908                 bucket_unlock(g);
 909                 percpu_up_read(&c->mark_lock);
 910         }
 911
 912         return 0;
 913 }
 914
 915 /*
 916  * This synthesizes deleted extents for holes, similar to BTREE_ITER_SLOTS for
 917  * extents style btrees, but works on non-extents btrees:
 918  */
 919 static struct bkey_s_c bch2_get_key_or_hole(struct btree_iter *iter, struct bpos end, struct bkey *hole)
 920 {
 921         struct bkey_s_c k = bch2_btree_iter_peek_slot(iter);
 922
 923         if (bkey_err(k))
 924                 return k;
 925
 926         if (k.k->type) {
 927                 return k;
 928         } else {
 929                 struct btree_iter iter2;
 930                 struct bpos next;
 931
 932                 bch2_trans_copy_iter(&iter2, iter);
 933
 934                 struct btree_path *path = btree_iter_path(iter->trans, iter);
 935                 if (!bpos_eq(path->l[0].b->key.k.p, SPOS_MAX))
 936                         end = bkey_min(end, bpos_nosnap_successor(path->l[0].b->key.k.p));
 937
 938                 end = bkey_min(end, POS(iter->pos.inode, iter->pos.offset + U32_MAX - 1));
 939
 940                 /*
 941                  * btree node min/max is a closed interval, upto takes a half
 942                  * open interval:
 943                  */
 944                 k = bch2_btree_iter_peek_upto(&iter2, end);
 945                 next = iter2.pos;
 946                 bch2_trans_iter_exit(iter->trans, &iter2);
 947
 948                 BUG_ON(next.offset >= iter->pos.offset + U32_MAX);
 949
 950                 if (bkey_err(k))
 951                         return k;
 952
 953                 bkey_init(hole);
 954                 hole->p = iter->pos;
 955
 956                 bch2_key_resize(hole, next.offset - iter->pos.offset);
 957                 return (struct bkey_s_c) { hole, NULL };
 958         }
 959 }
 960
 961 static bool next_bucket(struct bch_fs *c, struct bpos *bucket)
 962 {
 963         struct bch_dev *ca;
 964
 965         if (bch2_dev_bucket_exists(c, *bucket))
 966                 return true;
 967
 968         if (bch2_dev_exists2(c, bucket->inode)) {
 969                 ca = bch_dev_bkey_exists(c, bucket->inode);
 970
 971                 if (bucket->offset < ca->mi.first_bucket) {
 972                         bucket->offset = ca->mi.first_bucket;
 973                         return true;
 974                 }
 975
 976                 bucket->inode++;
 977                 bucket->offset = 0;
 978         }
 979
 980         rcu_read_lock();
 981         ca = __bch2_next_dev_idx(c, bucket->inode, NULL);
 982         if (ca)
 983                 *bucket = POS(ca->dev_idx, ca->mi.first_bucket);
 984         rcu_read_unlock();
 985
 986         return ca != NULL;
 987 }
 988
 989 static struct bkey_s_c bch2_get_key_or_real_bucket_hole(struct btree_iter *iter, struct bkey *hole)
 990 {
 991         struct bch_fs *c = iter->trans->c;
 992         struct bkey_s_c k;
 993 again:
 994         k = bch2_get_key_or_hole(iter, POS_MAX, hole);
 995         if (bkey_err(k))
 996                 return k;
 997
 998         if (!k.k->type) {
 999                 struct bpos bucket = bkey_start_pos(k.k);
1000
1001                 if (!bch2_dev_bucket_exists(c, bucket)) {
1002                         if (!next_bucket(c, &bucket))
1003                                 return bkey_s_c_null;
1004
1005                         bch2_btree_iter_set_pos(iter, bucket);
1006                         goto again;
1007                 }
1008
1009                 if (!bch2_dev_bucket_exists(c, k.k->p)) {
1010                         struct bch_dev *ca = bch_dev_bkey_exists(c, bucket.inode);
1011
1012                         bch2_key_resize(hole, ca->mi.nbuckets - bucket.offset);
1013                 }
1014         }
1015
1016         return k;
1017 }
1018
1019 static noinline_for_stack
1020 int bch2_check_alloc_key(struct btree_trans *trans,
1021                          struct bkey_s_c alloc_k,
1022                          struct btree_iter *alloc_iter,
1023                          struct btree_iter *discard_iter,
1024                          struct btree_iter *freespace_iter,
1025                          struct btree_iter *bucket_gens_iter)
1026 {
1027         struct bch_fs *c = trans->c;
1028         struct bch_dev *ca;
1029         struct bch_alloc_v4 a_convert;
1030         const struct bch_alloc_v4 *a;
1031         unsigned discard_key_type, freespace_key_type;
1032         unsigned gens_offset;
1033         struct bkey_s_c k;
1034         struct printbuf buf = PRINTBUF;
1035         int ret;
1036
1037         if (fsck_err_on(!bch2_dev_bucket_exists(c, alloc_k.k->p), c,
1038                         alloc_key_to_missing_dev_bucket,
1039                         "alloc key for invalid device:bucket %llu:%llu",
1040                         alloc_k.k->p.inode, alloc_k.k->p.offset))
1041                 return bch2_btree_delete_at(trans, alloc_iter, 0);
1042
1043         ca = bch_dev_bkey_exists(c, alloc_k.k->p.inode);
1044         if (!ca->mi.freespace_initialized)
1045                 return 0;
1046
1047         a = bch2_alloc_to_v4(alloc_k, &a_convert);
1048
1049         discard_key_type = a->data_type == BCH_DATA_need_discard ? KEY_TYPE_set : 0;
1050         bch2_btree_iter_set_pos(discard_iter, alloc_k.k->p);
1051         k = bch2_btree_iter_peek_slot(discard_iter);
1052         ret = bkey_err(k);
1053         if (ret)
1054                 goto err;
1055
1056         if (fsck_err_on(k.k->type != discard_key_type,
1057                         c, need_discard_key_wrong,
1058                         "incorrect key in need_discard btree (got %s should be %s)\n"
1059                         "  %s",
1060                         bch2_bkey_types[k.k->type],
1061                         bch2_bkey_types[discard_key_type],
1062                         (bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
1063                 struct bkey_i *update =
1064                         bch2_trans_kmalloc(trans, sizeof(*update));
1065
1066                 ret = PTR_ERR_OR_ZERO(update);
1067                 if (ret)
1068                         goto err;
1069
1070                 bkey_init(&update->k);
1071                 update->k.type  = discard_key_type;
1072                 update->k.p     = discard_iter->pos;
1073
1074                 ret = bch2_trans_update(trans, discard_iter, update, 0);
1075                 if (ret)
1076                         goto err;
1077         }
1078
1079         freespace_key_type = a->data_type == BCH_DATA_free ? KEY_TYPE_set : 0;
1080         bch2_btree_iter_set_pos(freespace_iter, alloc_freespace_pos(alloc_k.k->p, *a));
1081         k = bch2_btree_iter_peek_slot(freespace_iter);
1082         ret = bkey_err(k);
1083         if (ret)
1084                 goto err;
1085
1086         if (fsck_err_on(k.k->type != freespace_key_type,
1087                         c, freespace_key_wrong,
1088                         "incorrect key in freespace btree (got %s should be %s)\n"
1089                         "  %s",
1090                         bch2_bkey_types[k.k->type],
1091                         bch2_bkey_types[freespace_key_type],
1092                         (printbuf_reset(&buf),
1093                          bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
1094                 struct bkey_i *update =
1095                         bch2_trans_kmalloc(trans, sizeof(*update));
1096
1097                 ret = PTR_ERR_OR_ZERO(update);
1098                 if (ret)
1099                         goto err;
1100
1101                 bkey_init(&update->k);
1102                 update->k.type  = freespace_key_type;
1103                 update->k.p     = freespace_iter->pos;
1104                 bch2_key_resize(&update->k, 1);
1105
1106                 ret = bch2_trans_update(trans, freespace_iter, update, 0);
1107                 if (ret)
1108                         goto err;
1109         }
1110
1111         bch2_btree_iter_set_pos(bucket_gens_iter, alloc_gens_pos(alloc_k.k->p, &gens_offset));
1112         k = bch2_btree_iter_peek_slot(bucket_gens_iter);
1113         ret = bkey_err(k);
1114         if (ret)
1115                 goto err;
1116
1117         if (fsck_err_on(a->gen != alloc_gen(k, gens_offset),
1118                         c, bucket_gens_key_wrong,
1119                         "incorrect gen in bucket_gens btree (got %u should be %u)\n"
1120                         "  %s",
1121                         alloc_gen(k, gens_offset), a->gen,
1122                         (printbuf_reset(&buf),
1123                          bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
1124                 struct bkey_i_bucket_gens *g =
1125                         bch2_trans_kmalloc(trans, sizeof(*g));
1126
1127                 ret = PTR_ERR_OR_ZERO(g);
1128                 if (ret)
1129                         goto err;
1130
1131                 if (k.k->type == KEY_TYPE_bucket_gens) {
1132                         bkey_reassemble(&g->k_i, k);
1133                 } else {
1134                         bkey_bucket_gens_init(&g->k_i);
1135                         g->k.p = alloc_gens_pos(alloc_k.k->p, &gens_offset);
1136                 }
1137
1138                 g->v.gens[gens_offset] = a->gen;
1139
1140                 ret = bch2_trans_update(trans, bucket_gens_iter, &g->k_i, 0);
1141                 if (ret)
1142                         goto err;
1143         }
1144 err:
1145 fsck_err:
1146         printbuf_exit(&buf);
1147         return ret;
1148 }
1149
1150 static noinline_for_stack
1151 int bch2_check_alloc_hole_freespace(struct btree_trans *trans,
1152                                     struct bpos start,
1153                                     struct bpos *end,
1154                                     struct btree_iter *freespace_iter)
1155 {
1156         struct bch_fs *c = trans->c;
1157         struct bch_dev *ca;
1158         struct bkey_s_c k;
1159         struct printbuf buf = PRINTBUF;
1160         int ret;
1161
1162         ca = bch_dev_bkey_exists(c, start.inode);
1163         if (!ca->mi.freespace_initialized)
1164                 return 0;
1165
1166         bch2_btree_iter_set_pos(freespace_iter, start);
1167
1168         k = bch2_btree_iter_peek_slot(freespace_iter);
1169         ret = bkey_err(k);
1170         if (ret)
1171                 goto err;
1172
1173         *end = bkey_min(k.k->p, *end);
1174
1175         if (fsck_err_on(k.k->type != KEY_TYPE_set,
1176                         c, freespace_hole_missing,
1177                         "hole in alloc btree missing in freespace btree\n"
1178                         "  device %llu buckets %llu-%llu",
1179                         freespace_iter->pos.inode,
1180                         freespace_iter->pos.offset,
1181                         end->offset)) {
1182                 struct bkey_i *update =
1183                         bch2_trans_kmalloc(trans, sizeof(*update));
1184
1185                 ret = PTR_ERR_OR_ZERO(update);
1186                 if (ret)
1187                         goto err;
1188
1189                 bkey_init(&update->k);
1190                 update->k.type  = KEY_TYPE_set;
1191                 update->k.p     = freespace_iter->pos;
1192                 bch2_key_resize(&update->k,
1193                                 min_t(u64, U32_MAX, end->offset -
1194                                       freespace_iter->pos.offset));
1195
1196                 ret = bch2_trans_update(trans, freespace_iter, update, 0);
1197                 if (ret)
1198                         goto err;
1199         }
1200 err:
1201 fsck_err:
1202         printbuf_exit(&buf);
1203         return ret;
1204 }
1205
1206 static noinline_for_stack
1207 int bch2_check_alloc_hole_bucket_gens(struct btree_trans *trans,
1208                                       struct bpos start,
1209                                       struct bpos *end,
1210                                       struct btree_iter *bucket_gens_iter)
1211 {
1212         struct bch_fs *c = trans->c;
1213         struct bkey_s_c k;
1214         struct printbuf buf = PRINTBUF;
1215         unsigned i, gens_offset, gens_end_offset;
1216         int ret;
1217
1218         bch2_btree_iter_set_pos(bucket_gens_iter, alloc_gens_pos(start, &gens_offset));
1219
1220         k = bch2_btree_iter_peek_slot(bucket_gens_iter);
1221         ret = bkey_err(k);
1222         if (ret)
1223                 goto err;
1224
1225         if (bkey_cmp(alloc_gens_pos(start, &gens_offset),
1226                      alloc_gens_pos(*end,  &gens_end_offset)))
1227                 gens_end_offset = KEY_TYPE_BUCKET_GENS_NR;
1228
1229         if (k.k->type == KEY_TYPE_bucket_gens) {
1230                 struct bkey_i_bucket_gens g;
1231                 bool need_update = false;
1232
1233                 bkey_reassemble(&g.k_i, k);
1234
1235                 for (i = gens_offset; i < gens_end_offset; i++) {
1236                         if (fsck_err_on(g.v.gens[i], c,
1237                                         bucket_gens_hole_wrong,
1238                                         "hole in alloc btree at %llu:%llu with nonzero gen in bucket_gens btree (%u)",
1239                                         bucket_gens_pos_to_alloc(k.k->p, i).inode,
1240                                         bucket_gens_pos_to_alloc(k.k->p, i).offset,
1241                                         g.v.gens[i])) {
1242                                 g.v.gens[i] = 0;
1243                                 need_update = true;
1244                         }
1245                 }
1246
1247                 if (need_update) {
1248                         struct bkey_i *u = bch2_trans_kmalloc(trans, sizeof(g));
1249
1250                         ret = PTR_ERR_OR_ZERO(u);
1251                         if (ret)
1252                                 goto err;
1253
1254                         memcpy(u, &g, sizeof(g));
1255
1256                         ret = bch2_trans_update(trans, bucket_gens_iter, u, 0);
1257                         if (ret)
1258                                 goto err;
1259                 }
1260         }
1261
1262         *end = bkey_min(*end, bucket_gens_pos_to_alloc(bpos_nosnap_successor(k.k->p), 0));
1263 err:
1264 fsck_err:
1265         printbuf_exit(&buf);
1266         return ret;
1267 }
1268
1269 static noinline_for_stack int bch2_check_discard_freespace_key(struct btree_trans *trans,
1270                                               struct btree_iter *iter)
1271 {
1272         struct bch_fs *c = trans->c;
1273         struct btree_iter alloc_iter;
1274         struct bkey_s_c alloc_k;
1275         struct bch_alloc_v4 a_convert;
1276         const struct bch_alloc_v4 *a;
1277         u64 genbits;
1278         struct bpos pos;
1279         enum bch_data_type state = iter->btree_id == BTREE_ID_need_discard
1280                 ? BCH_DATA_need_discard
1281                 : BCH_DATA_free;
1282         struct printbuf buf = PRINTBUF;
1283         int ret;
1284
1285         pos = iter->pos;
1286         pos.offset &= ~(~0ULL << 56);
1287         genbits = iter->pos.offset & (~0ULL << 56);
1288
1289         alloc_k = bch2_bkey_get_iter(trans, &alloc_iter, BTREE_ID_alloc, pos, 0);
1290         ret = bkey_err(alloc_k);
1291         if (ret)
1292                 return ret;
1293
1294         if (fsck_err_on(!bch2_dev_bucket_exists(c, pos), c,
1295                         need_discard_freespace_key_to_invalid_dev_bucket,
1296                         "entry in %s btree for nonexistant dev:bucket %llu:%llu",
1297                         bch2_btree_id_str(iter->btree_id), pos.inode, pos.offset))
1298                 goto delete;
1299
1300         a = bch2_alloc_to_v4(alloc_k, &a_convert);
1301
1302         if (fsck_err_on(a->data_type != state ||
1303                         (state == BCH_DATA_free &&
1304                          genbits != alloc_freespace_genbits(*a)), c,
1305                         need_discard_freespace_key_bad,
1306                         "%s\n  incorrectly set at %s:%llu:%llu:0 (free %u, genbits %llu should be %llu)",
1307                         (bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf),
1308                         bch2_btree_id_str(iter->btree_id),
1309                         iter->pos.inode,
1310                         iter->pos.offset,
1311                         a->data_type == state,
1312                         genbits >> 56, alloc_freespace_genbits(*a) >> 56))
1313                 goto delete;
1314 out:
1315 fsck_err:
1316         set_btree_iter_dontneed(&alloc_iter);
1317         bch2_trans_iter_exit(trans, &alloc_iter);
1318         printbuf_exit(&buf);
1319         return ret;
1320 delete:
1321         ret =   bch2_btree_delete_extent_at(trans, iter,
1322                         iter->btree_id == BTREE_ID_freespace ? 1 : 0, 0) ?:
1323                 bch2_trans_commit(trans, NULL, NULL,
1324                         BCH_TRANS_COMMIT_no_enospc);
1325         goto out;
1326 }
1327
1328 /*
1329  * We've already checked that generation numbers in the bucket_gens btree are
1330  * valid for buckets that exist; this just checks for keys for nonexistent
1331  * buckets.
1332  */
1333 static noinline_for_stack
1334 int bch2_check_bucket_gens_key(struct btree_trans *trans,
1335                                struct btree_iter *iter,
1336                                struct bkey_s_c k)
1337 {
1338         struct bch_fs *c = trans->c;
1339         struct bkey_i_bucket_gens g;
1340         struct bch_dev *ca;
1341         u64 start = bucket_gens_pos_to_alloc(k.k->p, 0).offset;
1342         u64 end = bucket_gens_pos_to_alloc(bpos_nosnap_successor(k.k->p), 0).offset;
1343         u64 b;
1344         bool need_update = false, dev_exists;
1345         struct printbuf buf = PRINTBUF;
1346         int ret = 0;
1347
1348         BUG_ON(k.k->type != KEY_TYPE_bucket_gens);
1349         bkey_reassemble(&g.k_i, k);
1350
1351         /* if no bch_dev, skip out whether we repair or not */
1352         dev_exists = bch2_dev_exists2(c, k.k->p.inode);
1353         if (!dev_exists) {
1354                 if (fsck_err_on(!dev_exists, c,
1355                                 bucket_gens_to_invalid_dev,
1356                                 "bucket_gens key for invalid device:\n  %s",
1357                                 (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
1358                         ret = bch2_btree_delete_at(trans, iter, 0);
1359                 }
1360                 goto out;
1361         }
1362
1363         ca = bch_dev_bkey_exists(c, k.k->p.inode);
1364         if (fsck_err_on(end <= ca->mi.first_bucket ||
1365                         start >= ca->mi.nbuckets, c,
1366                         bucket_gens_to_invalid_buckets,
1367                         "bucket_gens key for invalid buckets:\n  %s",
1368                         (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
1369                 ret = bch2_btree_delete_at(trans, iter, 0);
1370                 goto out;
1371         }
1372
1373         for (b = start; b < ca->mi.first_bucket; b++)
1374                 if (fsck_err_on(g.v.gens[b & KEY_TYPE_BUCKET_GENS_MASK], c,
1375                                 bucket_gens_nonzero_for_invalid_buckets,
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_nonzero_for_invalid_buckets,
1384                                 "bucket_gens key has nonzero gen for invalid bucket")) {
1385                         g.v.gens[b & KEY_TYPE_BUCKET_GENS_MASK] = 0;
1386                         need_update = true;
1387                 }
1388
1389         if (need_update) {
1390                 struct bkey_i *u = bch2_trans_kmalloc(trans, sizeof(g));
1391
1392                 ret = PTR_ERR_OR_ZERO(u);
1393                 if (ret)
1394                         goto out;
1395
1396                 memcpy(u, &g, sizeof(g));
1397                 ret = bch2_trans_update(trans, iter, u, 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 = bch2_trans_get(c);
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_iter_init(trans, &iter, BTREE_ID_alloc, POS_MIN,
1414                              BTREE_ITER_PREFETCH);
1415         bch2_trans_iter_init(trans, &discard_iter, BTREE_ID_need_discard, POS_MIN,
1416                              BTREE_ITER_PREFETCH);
1417         bch2_trans_iter_init(trans, &freespace_iter, BTREE_ID_freespace, POS_MIN,
1418                              BTREE_ITER_PREFETCH);
1419         bch2_trans_iter_init(trans, &bucket_gens_iter, BTREE_ID_bucket_gens, POS_MIN,
1420                              BTREE_ITER_PREFETCH);
1421
1422         while (1) {
1423                 struct bpos next;
1424
1425                 bch2_trans_begin(trans);
1426
1427                 k = bch2_get_key_or_real_bucket_hole(&iter, &hole);
1428                 ret = bkey_err(k);
1429                 if (ret)
1430                         goto bkey_err;
1431
1432                 if (!k.k)
1433                         break;
1434
1435                 if (k.k->type) {
1436                         next = bpos_nosnap_successor(k.k->p);
1437
1438                         ret = bch2_check_alloc_key(trans,
1439                                                    k, &iter,
1440                                                    &discard_iter,
1441                                                    &freespace_iter,
1442                                                    &bucket_gens_iter);
1443                         if (ret)
1444                                 goto bkey_err;
1445                 } else {
1446                         next = k.k->p;
1447
1448                         ret = bch2_check_alloc_hole_freespace(trans,
1449                                                     bkey_start_pos(k.k),
1450                                                     &next,
1451                                                     &freespace_iter) ?:
1452                                 bch2_check_alloc_hole_bucket_gens(trans,
1453                                                     bkey_start_pos(k.k),
1454                                                     &next,
1455                                                     &bucket_gens_iter);
1456                         if (ret)
1457                                 goto bkey_err;
1458                 }
1459
1460                 ret = bch2_trans_commit(trans, NULL, NULL,
1461                                         BCH_TRANS_COMMIT_no_enospc);
1462                 if (ret)
1463                         goto bkey_err;
1464
1465                 bch2_btree_iter_set_pos(&iter, next);
1466 bkey_err:
1467                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
1468                         continue;
1469                 if (ret)
1470                         break;
1471         }
1472         bch2_trans_iter_exit(trans, &bucket_gens_iter);
1473         bch2_trans_iter_exit(trans, &freespace_iter);
1474         bch2_trans_iter_exit(trans, &discard_iter);
1475         bch2_trans_iter_exit(trans, &iter);
1476
1477         if (ret < 0)
1478                 goto err;
1479
1480         ret = for_each_btree_key(trans, iter,
1481                         BTREE_ID_need_discard, POS_MIN,
1482                         BTREE_ITER_PREFETCH, k,
1483                 bch2_check_discard_freespace_key(trans, &iter));
1484         if (ret)
1485                 goto err;
1486
1487         bch2_trans_iter_init(trans, &iter, BTREE_ID_freespace, POS_MIN,
1488                              BTREE_ITER_PREFETCH);
1489         while (1) {
1490                 bch2_trans_begin(trans);
1491                 k = bch2_btree_iter_peek(&iter);
1492                 if (!k.k)
1493                         break;
1494
1495                 ret = bkey_err(k) ?:
1496                         bch2_check_discard_freespace_key(trans, &iter);
1497                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) {
1498                         ret = 0;
1499                         continue;
1500                 }
1501                 if (ret) {
1502                         struct printbuf buf = PRINTBUF;
1503                         bch2_bkey_val_to_text(&buf, c, k);
1504
1505                         bch_err(c, "while checking %s", buf.buf);
1506                         printbuf_exit(&buf);
1507                         break;
1508                 }
1509
1510                 bch2_btree_iter_set_pos(&iter, bpos_nosnap_successor(iter.pos));
1511         }
1512         bch2_trans_iter_exit(trans, &iter);
1513         if (ret)
1514                 goto err;
1515
1516         ret = for_each_btree_key_commit(trans, iter,
1517                         BTREE_ID_bucket_gens, POS_MIN,
1518                         BTREE_ITER_PREFETCH, k,
1519                         NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
1520                 bch2_check_bucket_gens_key(trans, &iter, k));
1521 err:
1522         bch2_trans_put(trans);
1523         bch_err_fn(c, ret);
1524         return ret;
1525 }
1526
1527 static int bch2_check_alloc_to_lru_ref(struct btree_trans *trans,
1528                                        struct btree_iter *alloc_iter)
1529 {
1530         struct bch_fs *c = trans->c;
1531         struct btree_iter lru_iter;
1532         struct bch_alloc_v4 a_convert;
1533         const struct bch_alloc_v4 *a;
1534         struct bkey_s_c alloc_k, lru_k;
1535         struct printbuf buf = PRINTBUF;
1536         int ret;
1537
1538         alloc_k = bch2_btree_iter_peek(alloc_iter);
1539         if (!alloc_k.k)
1540                 return 0;
1541
1542         ret = bkey_err(alloc_k);
1543         if (ret)
1544                 return ret;
1545
1546         a = bch2_alloc_to_v4(alloc_k, &a_convert);
1547
1548         if (a->data_type != BCH_DATA_cached)
1549                 return 0;
1550
1551         if (fsck_err_on(!a->io_time[READ], c,
1552                         alloc_key_cached_but_read_time_zero,
1553                         "cached bucket with read_time 0\n"
1554                         "  %s",
1555                 (printbuf_reset(&buf),
1556                  bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
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] = atomic64_read(&c->io_clock[READ].now);
1564                 ret = bch2_trans_update(trans, alloc_iter,
1565                                         &a_mut->k_i, BTREE_TRIGGER_NORUN);
1566                 if (ret)
1567                         goto err;
1568
1569                 a = &a_mut->v;
1570         }
1571
1572         lru_k = bch2_bkey_get_iter(trans, &lru_iter, BTREE_ID_lru,
1573                              lru_pos(alloc_k.k->p.inode,
1574                                      bucket_to_u64(alloc_k.k->p),
1575                                      a->io_time[READ]), 0);
1576         ret = bkey_err(lru_k);
1577         if (ret)
1578                 return ret;
1579
1580         if (fsck_err_on(lru_k.k->type != KEY_TYPE_set, c,
1581                         alloc_key_to_missing_lru_entry,
1582                         "missing lru entry\n"
1583                         "  %s",
1584                         (printbuf_reset(&buf),
1585                          bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
1586                 ret = bch2_lru_set(trans,
1587                                    alloc_k.k->p.inode,
1588                                    bucket_to_u64(alloc_k.k->p),
1589                                    a->io_time[READ]);
1590                 if (ret)
1591                         goto err;
1592         }
1593 err:
1594 fsck_err:
1595         bch2_trans_iter_exit(trans, &lru_iter);
1596         printbuf_exit(&buf);
1597         return ret;
1598 }
1599
1600 int bch2_check_alloc_to_lru_refs(struct bch_fs *c)
1601 {
1602         int ret = bch2_trans_run(c,
1603                 for_each_btree_key_commit(trans, iter, BTREE_ID_alloc,
1604                                 POS_MIN, BTREE_ITER_PREFETCH, k,
1605                                 NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
1606                         bch2_check_alloc_to_lru_ref(trans, &iter)));
1607         bch_err_fn(c, ret);
1608         return ret;
1609 }
1610
1611 static int discard_in_flight_add(struct bch_fs *c, struct bpos bucket)
1612 {
1613         int ret;
1614
1615         mutex_lock(&c->discard_buckets_in_flight_lock);
1616         darray_for_each(c->discard_buckets_in_flight, i)
1617                 if (bkey_eq(*i, bucket)) {
1618                         ret = -EEXIST;
1619                         goto out;
1620                 }
1621
1622         ret = darray_push(&c->discard_buckets_in_flight, bucket);
1623 out:
1624         mutex_unlock(&c->discard_buckets_in_flight_lock);
1625         return ret;
1626 }
1627
1628 static void discard_in_flight_remove(struct bch_fs *c, struct bpos bucket)
1629 {
1630         mutex_lock(&c->discard_buckets_in_flight_lock);
1631         darray_for_each(c->discard_buckets_in_flight, i)
1632                 if (bkey_eq(*i, bucket)) {
1633                         darray_remove_item(&c->discard_buckets_in_flight, i);
1634                         goto found;
1635                 }
1636         BUG();
1637 found:
1638         mutex_unlock(&c->discard_buckets_in_flight_lock);
1639 }
1640
1641 struct discard_buckets_state {
1642         u64             seen;
1643         u64             open;
1644         u64             need_journal_commit;
1645         u64             discarded;
1646         struct bch_dev  *ca;
1647         u64             need_journal_commit_this_dev;
1648 };
1649
1650 static void discard_buckets_next_dev(struct bch_fs *c, struct discard_buckets_state *s, struct bch_dev *ca)
1651 {
1652         if (s->ca == ca)
1653                 return;
1654
1655         if (s->ca && s->need_journal_commit_this_dev >
1656             bch2_dev_usage_read(s->ca).d[BCH_DATA_free].buckets)
1657                 bch2_journal_flush_async(&c->journal, NULL);
1658
1659         if (s->ca)
1660                 percpu_ref_put(&s->ca->ref);
1661         if (ca)
1662                 percpu_ref_get(&ca->ref);
1663         s->ca = ca;
1664         s->need_journal_commit_this_dev = 0;
1665 }
1666
1667 static int bch2_discard_one_bucket(struct btree_trans *trans,
1668                                    struct btree_iter *need_discard_iter,
1669                                    struct bpos *discard_pos_done,
1670                                    struct discard_buckets_state *s)
1671 {
1672         struct bch_fs *c = trans->c;
1673         struct bpos pos = need_discard_iter->pos;
1674         struct btree_iter iter = { NULL };
1675         struct bkey_s_c k;
1676         struct bch_dev *ca;
1677         struct bkey_i_alloc_v4 *a;
1678         struct printbuf buf = PRINTBUF;
1679         bool discard_locked = false;
1680         int ret = 0;
1681
1682         ca = bch_dev_bkey_exists(c, pos.inode);
1683
1684         if (!percpu_ref_tryget(&ca->io_ref)) {
1685                 bch2_btree_iter_set_pos(need_discard_iter, POS(pos.inode + 1, 0));
1686                 return 0;
1687         }
1688
1689         discard_buckets_next_dev(c, s, ca);
1690
1691         if (bch2_bucket_is_open_safe(c, pos.inode, pos.offset)) {
1692                 s->open++;
1693                 goto out;
1694         }
1695
1696         if (bch2_bucket_needs_journal_commit(&c->buckets_waiting_for_journal,
1697                         c->journal.flushed_seq_ondisk,
1698                         pos.inode, pos.offset)) {
1699                 s->need_journal_commit++;
1700                 s->need_journal_commit_this_dev++;
1701                 goto out;
1702         }
1703
1704         k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_alloc,
1705                                need_discard_iter->pos,
1706                                BTREE_ITER_CACHED);
1707         ret = bkey_err(k);
1708         if (ret)
1709                 goto out;
1710
1711         a = bch2_alloc_to_v4_mut(trans, k);
1712         ret = PTR_ERR_OR_ZERO(a);
1713         if (ret)
1714                 goto out;
1715
1716         if (a->v.dirty_sectors) {
1717                 if (bch2_trans_inconsistent_on(c->curr_recovery_pass > BCH_RECOVERY_PASS_check_alloc_info,
1718                                                trans, "attempting to discard bucket with dirty data\n%s",
1719                                                (bch2_bkey_val_to_text(&buf, c, k), buf.buf)))
1720                         ret = -EIO;
1721                 goto out;
1722         }
1723
1724         if (a->v.data_type != BCH_DATA_need_discard) {
1725                 if (data_type_is_empty(a->v.data_type) &&
1726                     BCH_ALLOC_V4_NEED_INC_GEN(&a->v)) {
1727                         a->v.gen++;
1728                         SET_BCH_ALLOC_V4_NEED_INC_GEN(&a->v, false);
1729                         goto write;
1730                 }
1731
1732                 if (bch2_trans_inconsistent_on(c->curr_recovery_pass > BCH_RECOVERY_PASS_check_alloc_info,
1733                                                trans, "bucket incorrectly set in need_discard btree\n"
1734                                                "%s",
1735                                                (bch2_bkey_val_to_text(&buf, c, k), buf.buf)))
1736                         ret = -EIO;
1737                 goto out;
1738         }
1739
1740         if (a->v.journal_seq > c->journal.flushed_seq_ondisk) {
1741                 if (bch2_trans_inconsistent_on(c->curr_recovery_pass > BCH_RECOVERY_PASS_check_alloc_info,
1742                                                trans, "clearing need_discard but journal_seq %llu > flushed_seq %llu\n%s",
1743                                                a->v.journal_seq,
1744                                                c->journal.flushed_seq_ondisk,
1745                                                (bch2_bkey_val_to_text(&buf, c, k), buf.buf)))
1746                         ret = -EIO;
1747                 goto out;
1748         }
1749
1750         if (discard_in_flight_add(c, SPOS(iter.pos.inode, iter.pos.offset, true)))
1751                 goto out;
1752
1753         discard_locked = true;
1754
1755         if (!bkey_eq(*discard_pos_done, iter.pos) &&
1756             ca->mi.discard && !c->opts.nochanges) {
1757                 /*
1758                  * This works without any other locks because this is the only
1759                  * thread that removes items from the need_discard tree
1760                  */
1761                 bch2_trans_unlock_long(trans);
1762                 blkdev_issue_discard(ca->disk_sb.bdev,
1763                                      k.k->p.offset * ca->mi.bucket_size,
1764                                      ca->mi.bucket_size,
1765                                      GFP_KERNEL);
1766                 *discard_pos_done = iter.pos;
1767
1768                 ret = bch2_trans_relock_notrace(trans);
1769                 if (ret)
1770                         goto out;
1771         }
1772
1773         SET_BCH_ALLOC_V4_NEED_DISCARD(&a->v, false);
1774         a->v.data_type = alloc_data_type(a->v, a->v.data_type);
1775 write:
1776         ret =   bch2_trans_update(trans, &iter, &a->k_i, 0) ?:
1777                 bch2_trans_commit(trans, NULL, NULL,
1778                                   BCH_WATERMARK_btree|
1779                                   BCH_TRANS_COMMIT_no_enospc);
1780         if (ret)
1781                 goto out;
1782
1783         count_event(c, bucket_discard);
1784         s->discarded++;
1785 out:
1786         if (discard_locked)
1787                 discard_in_flight_remove(c, iter.pos);
1788         s->seen++;
1789         bch2_trans_iter_exit(trans, &iter);
1790         percpu_ref_put(&ca->io_ref);
1791         printbuf_exit(&buf);
1792         return ret;
1793 }
1794
1795 static void bch2_do_discards_work(struct work_struct *work)
1796 {
1797         struct bch_fs *c = container_of(work, struct bch_fs, discard_work);
1798         struct discard_buckets_state s = {};
1799         struct bpos discard_pos_done = POS_MAX;
1800         int ret;
1801
1802         /*
1803          * We're doing the commit in bch2_discard_one_bucket instead of using
1804          * for_each_btree_key_commit() so that we can increment counters after
1805          * successful commit:
1806          */
1807         ret = bch2_trans_run(c,
1808                 for_each_btree_key(trans, iter,
1809                                    BTREE_ID_need_discard, POS_MIN, 0, k,
1810                         bch2_discard_one_bucket(trans, &iter, &discard_pos_done, &s)));
1811
1812         discard_buckets_next_dev(c, &s, NULL);
1813
1814         trace_discard_buckets(c, s.seen, s.open, s.need_journal_commit, s.discarded,
1815                               bch2_err_str(ret));
1816
1817         bch2_write_ref_put(c, BCH_WRITE_REF_discard);
1818 }
1819
1820 void bch2_do_discards(struct bch_fs *c)
1821 {
1822         if (bch2_write_ref_tryget(c, BCH_WRITE_REF_discard) &&
1823             !queue_work(c->write_ref_wq, &c->discard_work))
1824                 bch2_write_ref_put(c, BCH_WRITE_REF_discard);
1825 }
1826
1827 static int bch2_clear_bucket_needs_discard(struct btree_trans *trans, struct bpos bucket)
1828 {
1829         struct btree_iter iter;
1830         bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc, bucket, BTREE_ITER_INTENT);
1831         struct bkey_s_c k = bch2_btree_iter_peek_slot(&iter);
1832         int ret = bkey_err(k);
1833         if (ret)
1834                 goto err;
1835
1836         struct bkey_i_alloc_v4 *a = bch2_alloc_to_v4_mut(trans, k);
1837         ret = PTR_ERR_OR_ZERO(a);
1838         if (ret)
1839                 goto err;
1840
1841         BUG_ON(a->v.dirty_sectors);
1842         SET_BCH_ALLOC_V4_NEED_DISCARD(&a->v, false);
1843         a->v.data_type = alloc_data_type(a->v, a->v.data_type);
1844
1845         ret = bch2_trans_update(trans, &iter, &a->k_i, 0);
1846 err:
1847         bch2_trans_iter_exit(trans, &iter);
1848         return ret;
1849 }
1850
1851 static void bch2_do_discards_fast_work(struct work_struct *work)
1852 {
1853         struct bch_fs *c = container_of(work, struct bch_fs, discard_fast_work);
1854
1855         while (1) {
1856                 bool got_bucket = false;
1857                 struct bpos bucket;
1858                 struct bch_dev *ca;
1859
1860                 mutex_lock(&c->discard_buckets_in_flight_lock);
1861                 darray_for_each(c->discard_buckets_in_flight, i) {
1862                         if (i->snapshot)
1863                                 continue;
1864
1865                         ca = bch_dev_bkey_exists(c, i->inode);
1866
1867                         if (!percpu_ref_tryget(&ca->io_ref)) {
1868                                 darray_remove_item(&c->discard_buckets_in_flight, i);
1869                                 continue;
1870                         }
1871
1872                         got_bucket = true;
1873                         bucket = *i;
1874                         i->snapshot = true;
1875                         break;
1876                 }
1877                 mutex_unlock(&c->discard_buckets_in_flight_lock);
1878
1879                 if (!got_bucket)
1880                         break;
1881
1882                 if (ca->mi.discard && !c->opts.nochanges)
1883                         blkdev_issue_discard(ca->disk_sb.bdev,
1884                                              bucket.offset * ca->mi.bucket_size,
1885                                              ca->mi.bucket_size,
1886                                              GFP_KERNEL);
1887
1888                 int ret = bch2_trans_do(c, NULL, NULL,
1889                                         BCH_WATERMARK_btree|
1890                                         BCH_TRANS_COMMIT_no_enospc,
1891                                         bch2_clear_bucket_needs_discard(trans, bucket));
1892                 bch_err_fn(c, ret);
1893
1894                 percpu_ref_put(&ca->io_ref);
1895                 discard_in_flight_remove(c, bucket);
1896
1897                 if (ret)
1898                         break;
1899         }
1900
1901         bch2_write_ref_put(c, BCH_WRITE_REF_discard_fast);
1902 }
1903
1904 static void bch2_discard_one_bucket_fast(struct bch_fs *c, struct bpos bucket)
1905 {
1906         struct bch_dev *ca = bch_dev_bkey_exists(c, bucket.inode);
1907
1908         if (!percpu_ref_is_dying(&ca->io_ref) &&
1909             !discard_in_flight_add(c, bucket) &&
1910             bch2_write_ref_tryget(c, BCH_WRITE_REF_discard_fast) &&
1911             !queue_work(c->write_ref_wq, &c->discard_fast_work))
1912                 bch2_write_ref_put(c, BCH_WRITE_REF_discard_fast);
1913 }
1914
1915 static int invalidate_one_bucket(struct btree_trans *trans,
1916                                  struct btree_iter *lru_iter,
1917                                  struct bkey_s_c lru_k,
1918                                  s64 *nr_to_invalidate)
1919 {
1920         struct bch_fs *c = trans->c;
1921         struct btree_iter alloc_iter = { NULL };
1922         struct bkey_i_alloc_v4 *a = NULL;
1923         struct printbuf buf = PRINTBUF;
1924         struct bpos bucket = u64_to_bucket(lru_k.k->p.offset);
1925         unsigned cached_sectors;
1926         int ret = 0;
1927
1928         if (*nr_to_invalidate <= 0)
1929                 return 1;
1930
1931         if (!bch2_dev_bucket_exists(c, bucket)) {
1932                 prt_str(&buf, "lru entry points to invalid bucket");
1933                 goto err;
1934         }
1935
1936         if (bch2_bucket_is_open_safe(c, bucket.inode, bucket.offset))
1937                 return 0;
1938
1939         a = bch2_trans_start_alloc_update(trans, &alloc_iter, bucket);
1940         ret = PTR_ERR_OR_ZERO(a);
1941         if (ret)
1942                 goto out;
1943
1944         /* We expect harmless races here due to the btree write buffer: */
1945         if (lru_pos_time(lru_iter->pos) != alloc_lru_idx_read(a->v))
1946                 goto out;
1947
1948         BUG_ON(a->v.data_type != BCH_DATA_cached);
1949         BUG_ON(a->v.dirty_sectors);
1950
1951         if (!a->v.cached_sectors)
1952                 bch_err(c, "invalidating empty bucket, confused");
1953
1954         cached_sectors = a->v.cached_sectors;
1955
1956         SET_BCH_ALLOC_V4_NEED_INC_GEN(&a->v, false);
1957         a->v.gen++;
1958         a->v.data_type          = 0;
1959         a->v.dirty_sectors      = 0;
1960         a->v.cached_sectors     = 0;
1961         a->v.io_time[READ]      = atomic64_read(&c->io_clock[READ].now);
1962         a->v.io_time[WRITE]     = atomic64_read(&c->io_clock[WRITE].now);
1963
1964         ret =   bch2_trans_update(trans, &alloc_iter, &a->k_i,
1965                                 BTREE_TRIGGER_BUCKET_INVALIDATE) ?:
1966                 bch2_trans_commit(trans, NULL, NULL,
1967                                   BCH_WATERMARK_btree|
1968                                   BCH_TRANS_COMMIT_no_enospc);
1969         if (ret)
1970                 goto out;
1971
1972         trace_and_count(c, bucket_invalidate, c, bucket.inode, bucket.offset, cached_sectors);
1973         --*nr_to_invalidate;
1974 out:
1975         bch2_trans_iter_exit(trans, &alloc_iter);
1976         printbuf_exit(&buf);
1977         return ret;
1978 err:
1979         prt_str(&buf, "\n  lru key: ");
1980         bch2_bkey_val_to_text(&buf, c, lru_k);
1981
1982         prt_str(&buf, "\n  lru entry: ");
1983         bch2_lru_pos_to_text(&buf, lru_iter->pos);
1984
1985         prt_str(&buf, "\n  alloc key: ");
1986         if (!a)
1987                 bch2_bpos_to_text(&buf, bucket);
1988         else
1989                 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&a->k_i));
1990
1991         bch_err(c, "%s", buf.buf);
1992         if (c->curr_recovery_pass > BCH_RECOVERY_PASS_check_lrus) {
1993                 bch2_inconsistent_error(c);
1994                 ret = -EINVAL;
1995         }
1996
1997         goto out;
1998 }
1999
2000 static void bch2_do_invalidates_work(struct work_struct *work)
2001 {
2002         struct bch_fs *c = container_of(work, struct bch_fs, invalidate_work);
2003         struct btree_trans *trans = bch2_trans_get(c);
2004         int ret = 0;
2005
2006         ret = bch2_btree_write_buffer_tryflush(trans);
2007         if (ret)
2008                 goto err;
2009
2010         for_each_member_device(c, ca) {
2011                 s64 nr_to_invalidate =
2012                         should_invalidate_buckets(ca, bch2_dev_usage_read(ca));
2013
2014                 ret = for_each_btree_key_upto(trans, iter, BTREE_ID_lru,
2015                                 lru_pos(ca->dev_idx, 0, 0),
2016                                 lru_pos(ca->dev_idx, U64_MAX, LRU_TIME_MAX),
2017                                 BTREE_ITER_INTENT, k,
2018                         invalidate_one_bucket(trans, &iter, k, &nr_to_invalidate));
2019
2020                 if (ret < 0) {
2021                         percpu_ref_put(&ca->ref);
2022                         break;
2023                 }
2024         }
2025 err:
2026         bch2_trans_put(trans);
2027         bch2_write_ref_put(c, BCH_WRITE_REF_invalidate);
2028 }
2029
2030 void bch2_do_invalidates(struct bch_fs *c)
2031 {
2032         if (bch2_write_ref_tryget(c, BCH_WRITE_REF_invalidate) &&
2033             !queue_work(c->write_ref_wq, &c->invalidate_work))
2034                 bch2_write_ref_put(c, BCH_WRITE_REF_invalidate);
2035 }
2036
2037 int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca,
2038                             u64 bucket_start, u64 bucket_end)
2039 {
2040         struct btree_trans *trans = bch2_trans_get(c);
2041         struct btree_iter iter;
2042         struct bkey_s_c k;
2043         struct bkey hole;
2044         struct bpos end = POS(ca->dev_idx, bucket_end);
2045         struct bch_member *m;
2046         unsigned long last_updated = jiffies;
2047         int ret;
2048
2049         BUG_ON(bucket_start > bucket_end);
2050         BUG_ON(bucket_end > ca->mi.nbuckets);
2051
2052         bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc,
2053                 POS(ca->dev_idx, max_t(u64, ca->mi.first_bucket, bucket_start)),
2054                 BTREE_ITER_PREFETCH);
2055         /*
2056          * Scan the alloc btree for every bucket on @ca, and add buckets to the
2057          * freespace/need_discard/need_gc_gens btrees as needed:
2058          */
2059         while (1) {
2060                 if (last_updated + HZ * 10 < jiffies) {
2061                         bch_info(ca, "%s: currently at %llu/%llu",
2062                                  __func__, iter.pos.offset, ca->mi.nbuckets);
2063                         last_updated = jiffies;
2064                 }
2065
2066                 bch2_trans_begin(trans);
2067
2068                 if (bkey_ge(iter.pos, end)) {
2069                         ret = 0;
2070                         break;
2071                 }
2072
2073                 k = bch2_get_key_or_hole(&iter, end, &hole);
2074                 ret = bkey_err(k);
2075                 if (ret)
2076                         goto bkey_err;
2077
2078                 if (k.k->type) {
2079                         /*
2080                          * We process live keys in the alloc btree one at a
2081                          * time:
2082                          */
2083                         struct bch_alloc_v4 a_convert;
2084                         const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, &a_convert);
2085
2086                         ret =   bch2_bucket_do_index(trans, k, a, true) ?:
2087                                 bch2_trans_commit(trans, NULL, NULL,
2088                                                   BCH_TRANS_COMMIT_no_enospc);
2089                         if (ret)
2090                                 goto bkey_err;
2091
2092                         bch2_btree_iter_advance(&iter);
2093                 } else {
2094                         struct bkey_i *freespace;
2095
2096                         freespace = bch2_trans_kmalloc(trans, sizeof(*freespace));
2097                         ret = PTR_ERR_OR_ZERO(freespace);
2098                         if (ret)
2099                                 goto bkey_err;
2100
2101                         bkey_init(&freespace->k);
2102                         freespace->k.type       = KEY_TYPE_set;
2103                         freespace->k.p          = k.k->p;
2104                         freespace->k.size       = k.k->size;
2105
2106                         ret = bch2_btree_insert_trans(trans, BTREE_ID_freespace, freespace, 0) ?:
2107                                 bch2_trans_commit(trans, NULL, NULL,
2108                                                   BCH_TRANS_COMMIT_no_enospc);
2109                         if (ret)
2110                                 goto bkey_err;
2111
2112                         bch2_btree_iter_set_pos(&iter, k.k->p);
2113                 }
2114 bkey_err:
2115                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
2116                         continue;
2117                 if (ret)
2118                         break;
2119         }
2120
2121         bch2_trans_iter_exit(trans, &iter);
2122         bch2_trans_put(trans);
2123
2124         if (ret < 0) {
2125                 bch_err_msg(ca, ret, "initializing free space");
2126                 return ret;
2127         }
2128
2129         mutex_lock(&c->sb_lock);
2130         m = bch2_members_v2_get_mut(c->disk_sb.sb, ca->dev_idx);
2131         SET_BCH_MEMBER_FREESPACE_INITIALIZED(m, true);
2132         mutex_unlock(&c->sb_lock);
2133
2134         return 0;
2135 }
2136
2137 int bch2_fs_freespace_init(struct bch_fs *c)
2138 {
2139         int ret = 0;
2140         bool doing_init = false;
2141
2142         /*
2143          * We can crash during the device add path, so we need to check this on
2144          * every mount:
2145          */
2146
2147         for_each_member_device(c, ca) {
2148                 if (ca->mi.freespace_initialized)
2149                         continue;
2150
2151                 if (!doing_init) {
2152                         bch_info(c, "initializing freespace");
2153                         doing_init = true;
2154                 }
2155
2156                 ret = bch2_dev_freespace_init(c, ca, 0, ca->mi.nbuckets);
2157                 if (ret) {
2158                         percpu_ref_put(&ca->ref);
2159                         bch_err_fn(c, ret);
2160                         return ret;
2161                 }
2162         }
2163
2164         if (doing_init) {
2165                 mutex_lock(&c->sb_lock);
2166                 bch2_write_super(c);
2167                 mutex_unlock(&c->sb_lock);
2168                 bch_verbose(c, "done initializing freespace");
2169         }
2170
2171         return 0;
2172 }
2173
2174 /* Bucket IO clocks: */
2175
2176 int bch2_bucket_io_time_reset(struct btree_trans *trans, unsigned dev,
2177                               size_t bucket_nr, int rw)
2178 {
2179         struct bch_fs *c = trans->c;
2180         struct btree_iter iter;
2181         struct bkey_i_alloc_v4 *a;
2182         u64 now;
2183         int ret = 0;
2184
2185         a = bch2_trans_start_alloc_update(trans, &iter,  POS(dev, bucket_nr));
2186         ret = PTR_ERR_OR_ZERO(a);
2187         if (ret)
2188                 return ret;
2189
2190         now = atomic64_read(&c->io_clock[rw].now);
2191         if (a->v.io_time[rw] == now)
2192                 goto out;
2193
2194         a->v.io_time[rw] = now;
2195
2196         ret   = bch2_trans_update(trans, &iter, &a->k_i, 0) ?:
2197                 bch2_trans_commit(trans, NULL, NULL, 0);
2198 out:
2199         bch2_trans_iter_exit(trans, &iter);
2200         return ret;
2201 }
2202
2203 /* Startup/shutdown (ro/rw): */
2204
2205 void bch2_recalc_capacity(struct bch_fs *c)
2206 {
2207         u64 capacity = 0, reserved_sectors = 0, gc_reserve;
2208         unsigned bucket_size_max = 0;
2209         unsigned long ra_pages = 0;
2210
2211         lockdep_assert_held(&c->state_lock);
2212
2213         for_each_online_member(c, ca) {
2214                 struct backing_dev_info *bdi = ca->disk_sb.bdev->bd_disk->bdi;
2215
2216                 ra_pages += bdi->ra_pages;
2217         }
2218
2219         bch2_set_ra_pages(c, ra_pages);
2220
2221         for_each_rw_member(c, ca) {
2222                 u64 dev_reserve = 0;
2223
2224                 /*
2225                  * We need to reserve buckets (from the number
2226                  * of currently available buckets) against
2227                  * foreground writes so that mainly copygc can
2228                  * make forward progress.
2229                  *
2230                  * We need enough to refill the various reserves
2231                  * from scratch - copygc will use its entire
2232                  * reserve all at once, then run against when
2233                  * its reserve is refilled (from the formerly
2234                  * available buckets).
2235                  *
2236                  * This reserve is just used when considering if
2237                  * allocations for foreground writes must wait -
2238                  * not -ENOSPC calculations.
2239                  */
2240
2241                 dev_reserve += ca->nr_btree_reserve * 2;
2242                 dev_reserve += ca->mi.nbuckets >> 6; /* copygc reserve */
2243
2244                 dev_reserve += 1;       /* btree write point */
2245                 dev_reserve += 1;       /* copygc write point */
2246                 dev_reserve += 1;       /* rebalance write point */
2247
2248                 dev_reserve *= ca->mi.bucket_size;
2249
2250                 capacity += bucket_to_sector(ca, ca->mi.nbuckets -
2251                                              ca->mi.first_bucket);
2252
2253                 reserved_sectors += dev_reserve * 2;
2254
2255                 bucket_size_max = max_t(unsigned, bucket_size_max,
2256                                         ca->mi.bucket_size);
2257         }
2258
2259         gc_reserve = c->opts.gc_reserve_bytes
2260                 ? c->opts.gc_reserve_bytes >> 9
2261                 : div64_u64(capacity * c->opts.gc_reserve_percent, 100);
2262
2263         reserved_sectors = max(gc_reserve, reserved_sectors);
2264
2265         reserved_sectors = min(reserved_sectors, capacity);
2266
2267         c->capacity = capacity - reserved_sectors;
2268
2269         c->bucket_size_max = bucket_size_max;
2270
2271         /* Wake up case someone was waiting for buckets */
2272         closure_wake_up(&c->freelist_wait);
2273 }
2274
2275 u64 bch2_min_rw_member_capacity(struct bch_fs *c)
2276 {
2277         u64 ret = U64_MAX;
2278
2279         for_each_rw_member(c, ca)
2280                 ret = min(ret, ca->mi.nbuckets * ca->mi.bucket_size);
2281         return ret;
2282 }
2283
2284 static bool bch2_dev_has_open_write_point(struct bch_fs *c, struct bch_dev *ca)
2285 {
2286         struct open_bucket *ob;
2287         bool ret = false;
2288
2289         for (ob = c->open_buckets;
2290              ob < c->open_buckets + ARRAY_SIZE(c->open_buckets);
2291              ob++) {
2292                 spin_lock(&ob->lock);
2293                 if (ob->valid && !ob->on_partial_list &&
2294                     ob->dev == ca->dev_idx)
2295                         ret = true;
2296                 spin_unlock(&ob->lock);
2297         }
2298
2299         return ret;
2300 }
2301
2302 /* device goes ro: */
2303 void bch2_dev_allocator_remove(struct bch_fs *c, struct bch_dev *ca)
2304 {
2305         unsigned i;
2306
2307         /* First, remove device from allocation groups: */
2308
2309         for (i = 0; i < ARRAY_SIZE(c->rw_devs); i++)
2310                 clear_bit(ca->dev_idx, c->rw_devs[i].d);
2311
2312         /*
2313          * Capacity is calculated based off of devices in allocation groups:
2314          */
2315         bch2_recalc_capacity(c);
2316
2317         bch2_open_buckets_stop(c, ca, false);
2318
2319         /*
2320          * Wake up threads that were blocked on allocation, so they can notice
2321          * the device can no longer be removed and the capacity has changed:
2322          */
2323         closure_wake_up(&c->freelist_wait);
2324
2325         /*
2326          * journal_res_get() can block waiting for free space in the journal -
2327          * it needs to notice there may not be devices to allocate from anymore:
2328          */
2329         wake_up(&c->journal.wait);
2330
2331         /* Now wait for any in flight writes: */
2332
2333         closure_wait_event(&c->open_buckets_wait,
2334                            !bch2_dev_has_open_write_point(c, ca));
2335 }
2336
2337 /* device goes rw: */
2338 void bch2_dev_allocator_add(struct bch_fs *c, struct bch_dev *ca)
2339 {
2340         unsigned i;
2341
2342         for (i = 0; i < ARRAY_SIZE(c->rw_devs); i++)
2343                 if (ca->mi.data_allowed & (1 << i))
2344                         set_bit(ca->dev_idx, c->rw_devs[i].d);
2345 }
2346
2347 void bch2_fs_allocator_background_exit(struct bch_fs *c)
2348 {
2349         darray_exit(&c->discard_buckets_in_flight);
2350 }
2351
2352 void bch2_fs_allocator_background_init(struct bch_fs *c)
2353 {
2354         spin_lock_init(&c->freelist_lock);
2355         mutex_init(&c->discard_buckets_in_flight_lock);
2356         INIT_WORK(&c->discard_work, bch2_do_discards_work);
2357         INIT_WORK(&c->discard_fast_work, bch2_do_discards_fast_work);
2358         INIT_WORK(&c->invalidate_work, bch2_do_invalidates_work);
2359 }