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 bch_validate_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 bch_validate_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 bch_validate_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 bch_validate_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_total(*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\n",     a->journal_seq);
 334         prt_printf(out, "need_discard      %llu\n",     BCH_ALLOC_V4_NEED_DISCARD(a));
 335         prt_printf(out, "need_inc_gen      %llu\n",     BCH_ALLOC_V4_NEED_INC_GEN(a));
 336         prt_printf(out, "dirty_sectors     %u\n",       a->dirty_sectors);
 337         prt_printf(out, "cached_sectors    %u\n",       a->cached_sectors);
 338         prt_printf(out, "stripe            %u\n",       a->stripe);
 339         prt_printf(out, "stripe_redundancy %u\n",       a->stripe_redundancy);
 340         prt_printf(out, "io_time[READ]     %llu\n",     a->io_time[READ]);
 341         prt_printf(out, "io_time[WRITE]    %llu\n",     a->io_time[WRITE]);
 342         prt_printf(out, "fragmentation     %llu\n",     a->fragmentation_lru);
 343         prt_printf(out, "bp_start          %llu\n", BCH_ALLOC_V4_BACKPOINTERS_START(a));
 344         printbuf_indent_sub(out, 2);
 345 }
 346
 347 void __bch2_alloc_to_v4(struct bkey_s_c k, struct bch_alloc_v4 *out)
 348 {
 349         if (k.k->type == KEY_TYPE_alloc_v4) {
 350                 void *src, *dst;
 351
 352                 *out = *bkey_s_c_to_alloc_v4(k).v;
 353
 354                 src = alloc_v4_backpointers(out);
 355                 SET_BCH_ALLOC_V4_BACKPOINTERS_START(out, BCH_ALLOC_V4_U64s);
 356                 dst = alloc_v4_backpointers(out);
 357
 358                 if (src < dst)
 359                         memset(src, 0, dst - src);
 360
 361                 SET_BCH_ALLOC_V4_NR_BACKPOINTERS(out, 0);
 362         } else {
 363                 struct bkey_alloc_unpacked u = bch2_alloc_unpack(k);
 364
 365                 *out = (struct bch_alloc_v4) {
 366                         .journal_seq            = u.journal_seq,
 367                         .flags                  = u.need_discard,
 368                         .gen                    = u.gen,
 369                         .oldest_gen             = u.oldest_gen,
 370                         .data_type              = u.data_type,
 371                         .stripe_redundancy      = u.stripe_redundancy,
 372                         .dirty_sectors          = u.dirty_sectors,
 373                         .cached_sectors         = u.cached_sectors,
 374                         .io_time[READ]          = u.read_time,
 375                         .io_time[WRITE]         = u.write_time,
 376                         .stripe                 = u.stripe,
 377                 };
 378
 379                 SET_BCH_ALLOC_V4_BACKPOINTERS_START(out, BCH_ALLOC_V4_U64s);
 380         }
 381 }
 382
 383 static noinline struct bkey_i_alloc_v4 *
 384 __bch2_alloc_to_v4_mut(struct btree_trans *trans, struct bkey_s_c k)
 385 {
 386         struct bkey_i_alloc_v4 *ret;
 387
 388         ret = bch2_trans_kmalloc(trans, max(bkey_bytes(k.k), sizeof(struct bkey_i_alloc_v4)));
 389         if (IS_ERR(ret))
 390                 return ret;
 391
 392         if (k.k->type == KEY_TYPE_alloc_v4) {
 393                 void *src, *dst;
 394
 395                 bkey_reassemble(&ret->k_i, k);
 396
 397                 src = alloc_v4_backpointers(&ret->v);
 398                 SET_BCH_ALLOC_V4_BACKPOINTERS_START(&ret->v, BCH_ALLOC_V4_U64s);
 399                 dst = alloc_v4_backpointers(&ret->v);
 400
 401                 if (src < dst)
 402                         memset(src, 0, dst - src);
 403
 404                 SET_BCH_ALLOC_V4_NR_BACKPOINTERS(&ret->v, 0);
 405                 set_alloc_v4_u64s(ret);
 406         } else {
 407                 bkey_alloc_v4_init(&ret->k_i);
 408                 ret->k.p = k.k->p;
 409                 bch2_alloc_to_v4(k, &ret->v);
 410         }
 411         return ret;
 412 }
 413
 414 static inline struct bkey_i_alloc_v4 *bch2_alloc_to_v4_mut_inlined(struct btree_trans *trans, struct bkey_s_c k)
 415 {
 416         struct bkey_s_c_alloc_v4 a;
 417
 418         if (likely(k.k->type == KEY_TYPE_alloc_v4) &&
 419             ((a = bkey_s_c_to_alloc_v4(k), true) &&
 420              BCH_ALLOC_V4_NR_BACKPOINTERS(a.v) == 0))
 421                 return bch2_bkey_make_mut_noupdate_typed(trans, k, alloc_v4);
 422
 423         return __bch2_alloc_to_v4_mut(trans, k);
 424 }
 425
 426 struct bkey_i_alloc_v4 *bch2_alloc_to_v4_mut(struct btree_trans *trans, struct bkey_s_c k)
 427 {
 428         return bch2_alloc_to_v4_mut_inlined(trans, k);
 429 }
 430
 431 struct bkey_i_alloc_v4 *
 432 bch2_trans_start_alloc_update_noupdate(struct btree_trans *trans, struct btree_iter *iter,
 433                                        struct bpos pos)
 434 {
 435         struct bkey_s_c k = bch2_bkey_get_iter(trans, iter, BTREE_ID_alloc, pos,
 436                                                BTREE_ITER_with_updates|
 437                                                BTREE_ITER_cached|
 438                                                BTREE_ITER_intent);
 439         int ret = bkey_err(k);
 440         if (unlikely(ret))
 441                 return ERR_PTR(ret);
 442
 443         struct bkey_i_alloc_v4 *a = bch2_alloc_to_v4_mut_inlined(trans, k);
 444         ret = PTR_ERR_OR_ZERO(a);
 445         if (unlikely(ret))
 446                 goto err;
 447         return a;
 448 err:
 449         bch2_trans_iter_exit(trans, iter);
 450         return ERR_PTR(ret);
 451 }
 452
 453 __flatten
 454 struct bkey_i_alloc_v4 *bch2_trans_start_alloc_update(struct btree_trans *trans, struct bpos pos)
 455 {
 456         struct btree_iter iter;
 457         struct bkey_i_alloc_v4 *a = bch2_trans_start_alloc_update_noupdate(trans, &iter, pos);
 458         int ret = PTR_ERR_OR_ZERO(a);
 459         if (ret)
 460                 return ERR_PTR(ret);
 461
 462         ret = bch2_trans_update(trans, &iter, &a->k_i, 0);
 463         bch2_trans_iter_exit(trans, &iter);
 464         return unlikely(ret) ? ERR_PTR(ret) : a;
 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 bch_validate_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         struct bch_dev *ca = NULL;
 571         int ret;
 572
 573         down_read(&c->gc_lock);
 574
 575         if (c->sb.version_upgrade_complete >= bcachefs_metadata_version_bucket_gens) {
 576                 ret = for_each_btree_key(trans, iter, BTREE_ID_bucket_gens, POS_MIN,
 577                                          BTREE_ITER_prefetch, k, ({
 578                         u64 start = bucket_gens_pos_to_alloc(k.k->p, 0).offset;
 579                         u64 end = bucket_gens_pos_to_alloc(bpos_nosnap_successor(k.k->p), 0).offset;
 580
 581                         if (k.k->type != KEY_TYPE_bucket_gens)
 582                                 continue;
 583
 584                         ca = bch2_dev_iterate(c, ca, k.k->p.inode);
 585                         /*
 586                          * Not a fsck error because this is checked/repaired by
 587                          * bch2_check_alloc_key() which runs later:
 588                          */
 589                         if (!ca) {
 590                                 bch2_btree_iter_set_pos(&iter, POS(k.k->p.inode + 1, 0));
 591                                 continue;
 592                         }
 593
 594                         const struct bch_bucket_gens *g = bkey_s_c_to_bucket_gens(k).v;
 595
 596                         for (u64 b = max_t(u64, ca->mi.first_bucket, start);
 597                              b < min_t(u64, ca->mi.nbuckets, end);
 598                              b++)
 599                                 *bucket_gen(ca, b) = g->gens[b & KEY_TYPE_BUCKET_GENS_MASK];
 600                         0;
 601                 }));
 602         } else {
 603                 ret = for_each_btree_key(trans, iter, BTREE_ID_alloc, POS_MIN,
 604                                          BTREE_ITER_prefetch, k, ({
 605                         ca = bch2_dev_iterate(c, ca, k.k->p.inode);
 606                         /*
 607                          * Not a fsck error because this is checked/repaired by
 608                          * bch2_check_alloc_key() which runs later:
 609                          */
 610                         if (!ca) {
 611                                 bch2_btree_iter_set_pos(&iter, POS(k.k->p.inode + 1, 0));
 612                                 continue;
 613                         }
 614
 615                         struct bch_alloc_v4 a;
 616                         *bucket_gen(ca, k.k->p.offset) = bch2_alloc_to_v4(k, &a)->gen;
 617                         0;
 618                 }));
 619         }
 620
 621         bch2_dev_put(ca);
 622         bch2_trans_put(trans);
 623         up_read(&c->gc_lock);
 624
 625         bch_err_fn(c, ret);
 626         return ret;
 627 }
 628
 629 /* Free space/discard btree: */
 630
 631 static int bch2_bucket_do_index(struct btree_trans *trans,
 632                                 struct bch_dev *ca,
 633                                 struct bkey_s_c alloc_k,
 634                                 const struct bch_alloc_v4 *a,
 635                                 bool set)
 636 {
 637         struct bch_fs *c = trans->c;
 638         struct btree_iter iter;
 639         struct bkey_s_c old;
 640         struct bkey_i *k;
 641         enum btree_id btree;
 642         enum bch_bkey_type old_type = !set ? KEY_TYPE_set : KEY_TYPE_deleted;
 643         enum bch_bkey_type new_type =  set ? KEY_TYPE_set : KEY_TYPE_deleted;
 644         struct printbuf buf = PRINTBUF;
 645         int ret;
 646
 647         if (a->data_type != BCH_DATA_free &&
 648             a->data_type != BCH_DATA_need_discard)
 649                 return 0;
 650
 651         k = bch2_trans_kmalloc_nomemzero(trans, sizeof(*k));
 652         if (IS_ERR(k))
 653                 return PTR_ERR(k);
 654
 655         bkey_init(&k->k);
 656         k->k.type = new_type;
 657
 658         switch (a->data_type) {
 659         case BCH_DATA_free:
 660                 btree = BTREE_ID_freespace;
 661                 k->k.p = alloc_freespace_pos(alloc_k.k->p, *a);
 662                 bch2_key_resize(&k->k, 1);
 663                 break;
 664         case BCH_DATA_need_discard:
 665                 btree = BTREE_ID_need_discard;
 666                 k->k.p = alloc_k.k->p;
 667                 break;
 668         default:
 669                 return 0;
 670         }
 671
 672         old = bch2_bkey_get_iter(trans, &iter, btree,
 673                              bkey_start_pos(&k->k),
 674                              BTREE_ITER_intent);
 675         ret = bkey_err(old);
 676         if (ret)
 677                 return ret;
 678
 679         if (ca->mi.freespace_initialized &&
 680             c->curr_recovery_pass > BCH_RECOVERY_PASS_check_alloc_info &&
 681             bch2_trans_inconsistent_on(old.k->type != old_type, trans,
 682                         "incorrect key when %s %s:%llu:%llu:0 (got %s should be %s)\n"
 683                         "  for %s",
 684                         set ? "setting" : "clearing",
 685                         bch2_btree_id_str(btree),
 686                         iter.pos.inode,
 687                         iter.pos.offset,
 688                         bch2_bkey_types[old.k->type],
 689                         bch2_bkey_types[old_type],
 690                         (bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
 691                 ret = -EIO;
 692                 goto err;
 693         }
 694
 695         ret = bch2_trans_update(trans, &iter, k, 0);
 696 err:
 697         bch2_trans_iter_exit(trans, &iter);
 698         printbuf_exit(&buf);
 699         return ret;
 700 }
 701
 702 static noinline int bch2_bucket_gen_update(struct btree_trans *trans,
 703                                            struct bpos bucket, u8 gen)
 704 {
 705         struct btree_iter iter;
 706         unsigned offset;
 707         struct bpos pos = alloc_gens_pos(bucket, &offset);
 708         struct bkey_i_bucket_gens *g;
 709         struct bkey_s_c k;
 710         int ret;
 711
 712         g = bch2_trans_kmalloc(trans, sizeof(*g));
 713         ret = PTR_ERR_OR_ZERO(g);
 714         if (ret)
 715                 return ret;
 716
 717         k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_bucket_gens, pos,
 718                                BTREE_ITER_intent|
 719                                BTREE_ITER_with_updates);
 720         ret = bkey_err(k);
 721         if (ret)
 722                 return ret;
 723
 724         if (k.k->type != KEY_TYPE_bucket_gens) {
 725                 bkey_bucket_gens_init(&g->k_i);
 726                 g->k.p = iter.pos;
 727         } else {
 728                 bkey_reassemble(&g->k_i, k);
 729         }
 730
 731         g->v.gens[offset] = gen;
 732
 733         ret = bch2_trans_update(trans, &iter, &g->k_i, 0);
 734         bch2_trans_iter_exit(trans, &iter);
 735         return ret;
 736 }
 737
 738 int bch2_trigger_alloc(struct btree_trans *trans,
 739                        enum btree_id btree, unsigned level,
 740                        struct bkey_s_c old, struct bkey_s new,
 741                        enum btree_iter_update_trigger_flags flags)
 742 {
 743         struct bch_fs *c = trans->c;
 744         int ret = 0;
 745
 746         struct bch_dev *ca = bch2_dev_bucket_tryget(c, new.k->p);
 747         if (!ca)
 748                 return -EIO;
 749
 750         struct bch_alloc_v4 old_a_convert;
 751         const struct bch_alloc_v4 *old_a = bch2_alloc_to_v4(old, &old_a_convert);
 752
 753         if (flags & BTREE_TRIGGER_transactional) {
 754                 struct bch_alloc_v4 *new_a = bkey_s_to_alloc_v4(new).v;
 755
 756                 alloc_data_type_set(new_a, new_a->data_type);
 757
 758                 if (bch2_bucket_sectors_total(*new_a) > bch2_bucket_sectors_total(*old_a)) {
 759                         new_a->io_time[READ] = max_t(u64, 1, atomic64_read(&c->io_clock[READ].now));
 760                         new_a->io_time[WRITE]= max_t(u64, 1, atomic64_read(&c->io_clock[WRITE].now));
 761                         SET_BCH_ALLOC_V4_NEED_INC_GEN(new_a, true);
 762                         SET_BCH_ALLOC_V4_NEED_DISCARD(new_a, true);
 763                 }
 764
 765                 if (data_type_is_empty(new_a->data_type) &&
 766                     BCH_ALLOC_V4_NEED_INC_GEN(new_a) &&
 767                     !bch2_bucket_is_open_safe(c, new.k->p.inode, new.k->p.offset)) {
 768                         new_a->gen++;
 769                         SET_BCH_ALLOC_V4_NEED_INC_GEN(new_a, false);
 770                 }
 771
 772                 if (old_a->data_type != new_a->data_type ||
 773                     (new_a->data_type == BCH_DATA_free &&
 774                      alloc_freespace_genbits(*old_a) != alloc_freespace_genbits(*new_a))) {
 775                         ret =   bch2_bucket_do_index(trans, ca, old, old_a, false) ?:
 776                                 bch2_bucket_do_index(trans, ca, new.s_c, new_a, true);
 777                         if (ret)
 778                                 goto err;
 779                 }
 780
 781                 if (new_a->data_type == BCH_DATA_cached &&
 782                     !new_a->io_time[READ])
 783                         new_a->io_time[READ] = max_t(u64, 1, atomic64_read(&c->io_clock[READ].now));
 784
 785                 u64 old_lru = alloc_lru_idx_read(*old_a);
 786                 u64 new_lru = alloc_lru_idx_read(*new_a);
 787                 if (old_lru != new_lru) {
 788                         ret = bch2_lru_change(trans, new.k->p.inode,
 789                                               bucket_to_u64(new.k->p),
 790                                               old_lru, new_lru);
 791                         if (ret)
 792                                 goto err;
 793                 }
 794
 795                 new_a->fragmentation_lru = alloc_lru_idx_fragmentation(*new_a, ca);
 796                 if (old_a->fragmentation_lru != new_a->fragmentation_lru) {
 797                         ret = bch2_lru_change(trans,
 798                                         BCH_LRU_FRAGMENTATION_START,
 799                                         bucket_to_u64(new.k->p),
 800                                         old_a->fragmentation_lru, new_a->fragmentation_lru);
 801                         if (ret)
 802                                 goto err;
 803                 }
 804
 805                 if (old_a->gen != new_a->gen) {
 806                         ret = bch2_bucket_gen_update(trans, new.k->p, new_a->gen);
 807                         if (ret)
 808                                 goto err;
 809                 }
 810
 811                 /*
 812                  * need to know if we're getting called from the invalidate path or
 813                  * not:
 814                  */
 815
 816                 if ((flags & BTREE_TRIGGER_bucket_invalidate) &&
 817                     old_a->cached_sectors) {
 818                         ret = bch2_update_cached_sectors_list(trans, new.k->p.inode,
 819                                                               -((s64) old_a->cached_sectors));
 820                         if (ret)
 821                                 goto err;
 822                 }
 823         }
 824
 825         if ((flags & BTREE_TRIGGER_atomic) && (flags & BTREE_TRIGGER_insert)) {
 826                 struct bch_alloc_v4 *new_a = bkey_s_to_alloc_v4(new).v;
 827                 u64 journal_seq = trans->journal_res.seq;
 828                 u64 bucket_journal_seq = new_a->journal_seq;
 829
 830                 if ((flags & BTREE_TRIGGER_insert) &&
 831                     data_type_is_empty(old_a->data_type) !=
 832                     data_type_is_empty(new_a->data_type) &&
 833                     new.k->type == KEY_TYPE_alloc_v4) {
 834                         struct bch_alloc_v4 *v = bkey_s_to_alloc_v4(new).v;
 835
 836                         /*
 837                          * If the btree updates referring to a bucket weren't flushed
 838                          * before the bucket became empty again, then the we don't have
 839                          * to wait on a journal flush before we can reuse the bucket:
 840                          */
 841                         v->journal_seq = bucket_journal_seq =
 842                                 data_type_is_empty(new_a->data_type) &&
 843                                 (journal_seq == v->journal_seq ||
 844                                  bch2_journal_noflush_seq(&c->journal, v->journal_seq))
 845                                 ? 0 : journal_seq;
 846                 }
 847
 848                 if (!data_type_is_empty(old_a->data_type) &&
 849                     data_type_is_empty(new_a->data_type) &&
 850                     bucket_journal_seq) {
 851                         ret = bch2_set_bucket_needs_journal_commit(&c->buckets_waiting_for_journal,
 852                                         c->journal.flushed_seq_ondisk,
 853                                         new.k->p.inode, new.k->p.offset,
 854                                         bucket_journal_seq);
 855                         if (ret) {
 856                                 bch2_fs_fatal_error(c,
 857                                         "setting bucket_needs_journal_commit: %s", bch2_err_str(ret));
 858                                 goto err;
 859                         }
 860                 }
 861
 862                 percpu_down_read(&c->mark_lock);
 863                 if (new_a->gen != old_a->gen)
 864                         *bucket_gen(ca, new.k->p.offset) = new_a->gen;
 865
 866                 bch2_dev_usage_update(c, ca, old_a, new_a, journal_seq, false);
 867                 percpu_up_read(&c->mark_lock);
 868
 869 #define eval_state(_a, expr)            ({ const struct bch_alloc_v4 *a = _a; expr; })
 870 #define statechange(expr)               !eval_state(old_a, expr) && eval_state(new_a, expr)
 871 #define bucket_flushed(a)               (!a->journal_seq || a->journal_seq <= c->journal.flushed_seq_ondisk)
 872
 873                 if (statechange(a->data_type == BCH_DATA_free) &&
 874                     bucket_flushed(new_a))
 875                         closure_wake_up(&c->freelist_wait);
 876
 877                 if (statechange(a->data_type == BCH_DATA_need_discard) &&
 878                     !bch2_bucket_is_open(c, new.k->p.inode, new.k->p.offset) &&
 879                     bucket_flushed(new_a))
 880                         bch2_discard_one_bucket_fast(c, new.k->p);
 881
 882                 if (statechange(a->data_type == BCH_DATA_cached) &&
 883                     !bch2_bucket_is_open(c, new.k->p.inode, new.k->p.offset) &&
 884                     should_invalidate_buckets(ca, bch2_dev_usage_read(ca)))
 885                         bch2_do_invalidates(c);
 886
 887                 if (statechange(a->data_type == BCH_DATA_need_gc_gens))
 888                         bch2_gc_gens_async(c);
 889         }
 890
 891         if ((flags & BTREE_TRIGGER_gc) &&
 892             (flags & BTREE_TRIGGER_bucket_invalidate)) {
 893                 struct bch_alloc_v4 new_a_convert;
 894                 const struct bch_alloc_v4 *new_a = bch2_alloc_to_v4(new.s_c, &new_a_convert);
 895
 896                 percpu_down_read(&c->mark_lock);
 897                 struct bucket *g = gc_bucket(ca, new.k->p.offset);
 898
 899                 bucket_lock(g);
 900
 901                 g->gen_valid            = 1;
 902                 g->gen                  = new_a->gen;
 903                 g->data_type            = new_a->data_type;
 904                 g->stripe               = new_a->stripe;
 905                 g->stripe_redundancy    = new_a->stripe_redundancy;
 906                 g->dirty_sectors        = new_a->dirty_sectors;
 907                 g->cached_sectors       = new_a->cached_sectors;
 908
 909                 bucket_unlock(g);
 910                 percpu_up_read(&c->mark_lock);
 911         }
 912 err:
 913         bch2_dev_put(ca);
 914         return ret;
 915 }
 916
 917 /*
 918  * This synthesizes deleted extents for holes, similar to BTREE_ITER_slots for
 919  * extents style btrees, but works on non-extents btrees:
 920  */
 921 static struct bkey_s_c bch2_get_key_or_hole(struct btree_iter *iter, struct bpos end, struct bkey *hole)
 922 {
 923         struct bkey_s_c k = bch2_btree_iter_peek_slot(iter);
 924
 925         if (bkey_err(k))
 926                 return k;
 927
 928         if (k.k->type) {
 929                 return k;
 930         } else {
 931                 struct btree_iter iter2;
 932                 struct bpos next;
 933
 934                 bch2_trans_copy_iter(&iter2, iter);
 935
 936                 struct btree_path *path = btree_iter_path(iter->trans, iter);
 937                 if (!bpos_eq(path->l[0].b->key.k.p, SPOS_MAX))
 938                         end = bkey_min(end, bpos_nosnap_successor(path->l[0].b->key.k.p));
 939
 940                 end = bkey_min(end, POS(iter->pos.inode, iter->pos.offset + U32_MAX - 1));
 941
 942                 /*
 943                  * btree node min/max is a closed interval, upto takes a half
 944                  * open interval:
 945                  */
 946                 k = bch2_btree_iter_peek_upto(&iter2, end);
 947                 next = iter2.pos;
 948                 bch2_trans_iter_exit(iter->trans, &iter2);
 949
 950                 BUG_ON(next.offset >= iter->pos.offset + U32_MAX);
 951
 952                 if (bkey_err(k))
 953                         return k;
 954
 955                 bkey_init(hole);
 956                 hole->p = iter->pos;
 957
 958                 bch2_key_resize(hole, next.offset - iter->pos.offset);
 959                 return (struct bkey_s_c) { hole, NULL };
 960         }
 961 }
 962
 963 static bool next_bucket(struct bch_fs *c, struct bch_dev **ca, struct bpos *bucket)
 964 {
 965         if (*ca) {
 966                 if (bucket->offset < (*ca)->mi.first_bucket)
 967                         bucket->offset = (*ca)->mi.first_bucket;
 968
 969                 if (bucket->offset < (*ca)->mi.nbuckets)
 970                         return true;
 971
 972                 bch2_dev_put(*ca);
 973                 *ca = NULL;
 974                 bucket->inode++;
 975                 bucket->offset = 0;
 976         }
 977
 978         rcu_read_lock();
 979         *ca = __bch2_next_dev_idx(c, bucket->inode, NULL);
 980         if (*ca) {
 981                 *bucket = POS((*ca)->dev_idx, (*ca)->mi.first_bucket);
 982                 bch2_dev_get(*ca);
 983         }
 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,
 990                                         struct bch_dev **ca, struct bkey *hole)
 991 {
 992         struct bch_fs *c = iter->trans->c;
 993         struct bkey_s_c k;
 994 again:
 995         k = bch2_get_key_or_hole(iter, POS_MAX, hole);
 996         if (bkey_err(k))
 997                 return k;
 998
 999         *ca = bch2_dev_iterate_noerror(c, *ca, k.k->p.inode);
1000
1001         if (!k.k->type) {
1002                 struct bpos hole_start = bkey_start_pos(k.k);
1003
1004                 if (!*ca || !bucket_valid(*ca, hole_start.offset)) {
1005                         if (!next_bucket(c, ca, &hole_start))
1006                                 return bkey_s_c_null;
1007
1008                         bch2_btree_iter_set_pos(iter, hole_start);
1009                         goto again;
1010                 }
1011
1012                 if (k.k->p.offset > (*ca)->mi.nbuckets)
1013                         bch2_key_resize(hole, (*ca)->mi.nbuckets - hole_start.offset);
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_alloc_v4 a_convert;
1029         const struct bch_alloc_v4 *a;
1030         unsigned discard_key_type, freespace_key_type;
1031         unsigned gens_offset;
1032         struct bkey_s_c k;
1033         struct printbuf buf = PRINTBUF;
1034         int ret = 0;
1035
1036         struct bch_dev *ca = bch2_dev_bucket_tryget_noerror(c, alloc_k.k->p);
1037         if (fsck_err_on(!ca,
1038                         c, 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                 ret = bch2_btree_delete_at(trans, alloc_iter, 0);
1042         if (!ca)
1043                 return ret;
1044
1045         if (!ca->mi.freespace_initialized)
1046                 goto out;
1047
1048         a = bch2_alloc_to_v4(alloc_k, &a_convert);
1049
1050         discard_key_type = a->data_type == BCH_DATA_need_discard ? KEY_TYPE_set : 0;
1051         bch2_btree_iter_set_pos(discard_iter, alloc_k.k->p);
1052         k = bch2_btree_iter_peek_slot(discard_iter);
1053         ret = bkey_err(k);
1054         if (ret)
1055                 goto err;
1056
1057         if (fsck_err_on(k.k->type != discard_key_type,
1058                         c, need_discard_key_wrong,
1059                         "incorrect key in need_discard btree (got %s should be %s)\n"
1060                         "  %s",
1061                         bch2_bkey_types[k.k->type],
1062                         bch2_bkey_types[discard_key_type],
1063                         (bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
1064                 struct bkey_i *update =
1065                         bch2_trans_kmalloc(trans, sizeof(*update));
1066
1067                 ret = PTR_ERR_OR_ZERO(update);
1068                 if (ret)
1069                         goto err;
1070
1071                 bkey_init(&update->k);
1072                 update->k.type  = discard_key_type;
1073                 update->k.p     = discard_iter->pos;
1074
1075                 ret = bch2_trans_update(trans, discard_iter, update, 0);
1076                 if (ret)
1077                         goto err;
1078         }
1079
1080         freespace_key_type = a->data_type == BCH_DATA_free ? KEY_TYPE_set : 0;
1081         bch2_btree_iter_set_pos(freespace_iter, alloc_freespace_pos(alloc_k.k->p, *a));
1082         k = bch2_btree_iter_peek_slot(freespace_iter);
1083         ret = bkey_err(k);
1084         if (ret)
1085                 goto err;
1086
1087         if (fsck_err_on(k.k->type != freespace_key_type,
1088                         c, freespace_key_wrong,
1089                         "incorrect key in freespace btree (got %s should be %s)\n"
1090                         "  %s",
1091                         bch2_bkey_types[k.k->type],
1092                         bch2_bkey_types[freespace_key_type],
1093                         (printbuf_reset(&buf),
1094                          bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
1095                 struct bkey_i *update =
1096                         bch2_trans_kmalloc(trans, sizeof(*update));
1097
1098                 ret = PTR_ERR_OR_ZERO(update);
1099                 if (ret)
1100                         goto err;
1101
1102                 bkey_init(&update->k);
1103                 update->k.type  = freespace_key_type;
1104                 update->k.p     = freespace_iter->pos;
1105                 bch2_key_resize(&update->k, 1);
1106
1107                 ret = bch2_trans_update(trans, freespace_iter, update, 0);
1108                 if (ret)
1109                         goto err;
1110         }
1111
1112         bch2_btree_iter_set_pos(bucket_gens_iter, alloc_gens_pos(alloc_k.k->p, &gens_offset));
1113         k = bch2_btree_iter_peek_slot(bucket_gens_iter);
1114         ret = bkey_err(k);
1115         if (ret)
1116                 goto err;
1117
1118         if (fsck_err_on(a->gen != alloc_gen(k, gens_offset),
1119                         c, bucket_gens_key_wrong,
1120                         "incorrect gen in bucket_gens btree (got %u should be %u)\n"
1121                         "  %s",
1122                         alloc_gen(k, gens_offset), a->gen,
1123                         (printbuf_reset(&buf),
1124                          bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
1125                 struct bkey_i_bucket_gens *g =
1126                         bch2_trans_kmalloc(trans, sizeof(*g));
1127
1128                 ret = PTR_ERR_OR_ZERO(g);
1129                 if (ret)
1130                         goto err;
1131
1132                 if (k.k->type == KEY_TYPE_bucket_gens) {
1133                         bkey_reassemble(&g->k_i, k);
1134                 } else {
1135                         bkey_bucket_gens_init(&g->k_i);
1136                         g->k.p = alloc_gens_pos(alloc_k.k->p, &gens_offset);
1137                 }
1138
1139                 g->v.gens[gens_offset] = a->gen;
1140
1141                 ret = bch2_trans_update(trans, bucket_gens_iter, &g->k_i, 0);
1142                 if (ret)
1143                         goto err;
1144         }
1145 out:
1146 err:
1147 fsck_err:
1148         bch2_dev_put(ca);
1149         printbuf_exit(&buf);
1150         return ret;
1151 }
1152
1153 static noinline_for_stack
1154 int bch2_check_alloc_hole_freespace(struct btree_trans *trans,
1155                                     struct bch_dev *ca,
1156                                     struct bpos start,
1157                                     struct bpos *end,
1158                                     struct btree_iter *freespace_iter)
1159 {
1160         struct bch_fs *c = trans->c;
1161         struct bkey_s_c k;
1162         struct printbuf buf = PRINTBUF;
1163         int ret;
1164
1165         if (!ca->mi.freespace_initialized)
1166                 return 0;
1167
1168         bch2_btree_iter_set_pos(freespace_iter, start);
1169
1170         k = bch2_btree_iter_peek_slot(freespace_iter);
1171         ret = bkey_err(k);
1172         if (ret)
1173                 goto err;
1174
1175         *end = bkey_min(k.k->p, *end);
1176
1177         if (fsck_err_on(k.k->type != KEY_TYPE_set,
1178                         c, freespace_hole_missing,
1179                         "hole in alloc btree missing in freespace btree\n"
1180                         "  device %llu buckets %llu-%llu",
1181                         freespace_iter->pos.inode,
1182                         freespace_iter->pos.offset,
1183                         end->offset)) {
1184                 struct bkey_i *update =
1185                         bch2_trans_kmalloc(trans, sizeof(*update));
1186
1187                 ret = PTR_ERR_OR_ZERO(update);
1188                 if (ret)
1189                         goto err;
1190
1191                 bkey_init(&update->k);
1192                 update->k.type  = KEY_TYPE_set;
1193                 update->k.p     = freespace_iter->pos;
1194                 bch2_key_resize(&update->k,
1195                                 min_t(u64, U32_MAX, end->offset -
1196                                       freespace_iter->pos.offset));
1197
1198                 ret = bch2_trans_update(trans, freespace_iter, update, 0);
1199                 if (ret)
1200                         goto err;
1201         }
1202 err:
1203 fsck_err:
1204         printbuf_exit(&buf);
1205         return ret;
1206 }
1207
1208 static noinline_for_stack
1209 int bch2_check_alloc_hole_bucket_gens(struct btree_trans *trans,
1210                                       struct bpos start,
1211                                       struct bpos *end,
1212                                       struct btree_iter *bucket_gens_iter)
1213 {
1214         struct bch_fs *c = trans->c;
1215         struct bkey_s_c k;
1216         struct printbuf buf = PRINTBUF;
1217         unsigned i, gens_offset, gens_end_offset;
1218         int ret;
1219
1220         bch2_btree_iter_set_pos(bucket_gens_iter, alloc_gens_pos(start, &gens_offset));
1221
1222         k = bch2_btree_iter_peek_slot(bucket_gens_iter);
1223         ret = bkey_err(k);
1224         if (ret)
1225                 goto err;
1226
1227         if (bkey_cmp(alloc_gens_pos(start, &gens_offset),
1228                      alloc_gens_pos(*end,  &gens_end_offset)))
1229                 gens_end_offset = KEY_TYPE_BUCKET_GENS_NR;
1230
1231         if (k.k->type == KEY_TYPE_bucket_gens) {
1232                 struct bkey_i_bucket_gens g;
1233                 bool need_update = false;
1234
1235                 bkey_reassemble(&g.k_i, k);
1236
1237                 for (i = gens_offset; i < gens_end_offset; i++) {
1238                         if (fsck_err_on(g.v.gens[i], c,
1239                                         bucket_gens_hole_wrong,
1240                                         "hole in alloc btree at %llu:%llu with nonzero gen in bucket_gens btree (%u)",
1241                                         bucket_gens_pos_to_alloc(k.k->p, i).inode,
1242                                         bucket_gens_pos_to_alloc(k.k->p, i).offset,
1243                                         g.v.gens[i])) {
1244                                 g.v.gens[i] = 0;
1245                                 need_update = true;
1246                         }
1247                 }
1248
1249                 if (need_update) {
1250                         struct bkey_i *u = bch2_trans_kmalloc(trans, sizeof(g));
1251
1252                         ret = PTR_ERR_OR_ZERO(u);
1253                         if (ret)
1254                                 goto err;
1255
1256                         memcpy(u, &g, sizeof(g));
1257
1258                         ret = bch2_trans_update(trans, bucket_gens_iter, u, 0);
1259                         if (ret)
1260                                 goto err;
1261                 }
1262         }
1263
1264         *end = bkey_min(*end, bucket_gens_pos_to_alloc(bpos_nosnap_successor(k.k->p), 0));
1265 err:
1266 fsck_err:
1267         printbuf_exit(&buf);
1268         return ret;
1269 }
1270
1271 static noinline_for_stack int bch2_check_discard_freespace_key(struct btree_trans *trans,
1272                                               struct btree_iter *iter)
1273 {
1274         struct bch_fs *c = trans->c;
1275         struct btree_iter alloc_iter;
1276         struct bkey_s_c alloc_k;
1277         struct bch_alloc_v4 a_convert;
1278         const struct bch_alloc_v4 *a;
1279         u64 genbits;
1280         struct bpos pos;
1281         enum bch_data_type state = iter->btree_id == BTREE_ID_need_discard
1282                 ? BCH_DATA_need_discard
1283                 : BCH_DATA_free;
1284         struct printbuf buf = PRINTBUF;
1285         int ret;
1286
1287         pos = iter->pos;
1288         pos.offset &= ~(~0ULL << 56);
1289         genbits = iter->pos.offset & (~0ULL << 56);
1290
1291         alloc_k = bch2_bkey_get_iter(trans, &alloc_iter, BTREE_ID_alloc, pos, 0);
1292         ret = bkey_err(alloc_k);
1293         if (ret)
1294                 return ret;
1295
1296         if (fsck_err_on(!bch2_dev_bucket_exists(c, pos), c,
1297                         need_discard_freespace_key_to_invalid_dev_bucket,
1298                         "entry in %s btree for nonexistant dev:bucket %llu:%llu",
1299                         bch2_btree_id_str(iter->btree_id), pos.inode, pos.offset))
1300                 goto delete;
1301
1302         a = bch2_alloc_to_v4(alloc_k, &a_convert);
1303
1304         if (fsck_err_on(a->data_type != state ||
1305                         (state == BCH_DATA_free &&
1306                          genbits != alloc_freespace_genbits(*a)), c,
1307                         need_discard_freespace_key_bad,
1308                         "%s\n  incorrectly set at %s:%llu:%llu:0 (free %u, genbits %llu should be %llu)",
1309                         (bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf),
1310                         bch2_btree_id_str(iter->btree_id),
1311                         iter->pos.inode,
1312                         iter->pos.offset,
1313                         a->data_type == state,
1314                         genbits >> 56, alloc_freespace_genbits(*a) >> 56))
1315                 goto delete;
1316 out:
1317 fsck_err:
1318         bch2_set_btree_iter_dontneed(&alloc_iter);
1319         bch2_trans_iter_exit(trans, &alloc_iter);
1320         printbuf_exit(&buf);
1321         return ret;
1322 delete:
1323         ret =   bch2_btree_delete_extent_at(trans, iter,
1324                         iter->btree_id == BTREE_ID_freespace ? 1 : 0, 0) ?:
1325                 bch2_trans_commit(trans, NULL, NULL,
1326                         BCH_TRANS_COMMIT_no_enospc);
1327         goto out;
1328 }
1329
1330 /*
1331  * We've already checked that generation numbers in the bucket_gens btree are
1332  * valid for buckets that exist; this just checks for keys for nonexistent
1333  * buckets.
1334  */
1335 static noinline_for_stack
1336 int bch2_check_bucket_gens_key(struct btree_trans *trans,
1337                                struct btree_iter *iter,
1338                                struct bkey_s_c k)
1339 {
1340         struct bch_fs *c = trans->c;
1341         struct bkey_i_bucket_gens g;
1342         u64 start = bucket_gens_pos_to_alloc(k.k->p, 0).offset;
1343         u64 end = bucket_gens_pos_to_alloc(bpos_nosnap_successor(k.k->p), 0).offset;
1344         u64 b;
1345         bool need_update = false;
1346         struct printbuf buf = PRINTBUF;
1347         int ret = 0;
1348
1349         BUG_ON(k.k->type != KEY_TYPE_bucket_gens);
1350         bkey_reassemble(&g.k_i, k);
1351
1352         struct bch_dev *ca = bch2_dev_tryget_noerror(c, k.k->p.inode);
1353         if (!ca) {
1354                 if (fsck_err(c, bucket_gens_to_invalid_dev,
1355                              "bucket_gens key for invalid device:\n  %s",
1356                              (bch2_bkey_val_to_text(&buf, c, k), buf.buf)))
1357                         ret = bch2_btree_delete_at(trans, iter, 0);
1358                 goto out;
1359         }
1360
1361         if (fsck_err_on(end <= ca->mi.first_bucket ||
1362                         start >= ca->mi.nbuckets, c,
1363                         bucket_gens_to_invalid_buckets,
1364                         "bucket_gens key for invalid buckets:\n  %s",
1365                         (bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
1366                 ret = bch2_btree_delete_at(trans, iter, 0);
1367                 goto out;
1368         }
1369
1370         for (b = start; b < ca->mi.first_bucket; b++)
1371                 if (fsck_err_on(g.v.gens[b & KEY_TYPE_BUCKET_GENS_MASK], c,
1372                                 bucket_gens_nonzero_for_invalid_buckets,
1373                                 "bucket_gens key has nonzero gen for invalid bucket")) {
1374                         g.v.gens[b & KEY_TYPE_BUCKET_GENS_MASK] = 0;
1375                         need_update = true;
1376                 }
1377
1378         for (b = ca->mi.nbuckets; b < end; b++)
1379                 if (fsck_err_on(g.v.gens[b & KEY_TYPE_BUCKET_GENS_MASK], c,
1380                                 bucket_gens_nonzero_for_invalid_buckets,
1381                                 "bucket_gens key has nonzero gen for invalid bucket")) {
1382                         g.v.gens[b & KEY_TYPE_BUCKET_GENS_MASK] = 0;
1383                         need_update = true;
1384                 }
1385
1386         if (need_update) {
1387                 struct bkey_i *u = bch2_trans_kmalloc(trans, sizeof(g));
1388
1389                 ret = PTR_ERR_OR_ZERO(u);
1390                 if (ret)
1391                         goto out;
1392
1393                 memcpy(u, &g, sizeof(g));
1394                 ret = bch2_trans_update(trans, iter, u, 0);
1395         }
1396 out:
1397 fsck_err:
1398         bch2_dev_put(ca);
1399         printbuf_exit(&buf);
1400         return ret;
1401 }
1402
1403 int bch2_check_alloc_info(struct bch_fs *c)
1404 {
1405         struct btree_trans *trans = bch2_trans_get(c);
1406         struct btree_iter iter, discard_iter, freespace_iter, bucket_gens_iter;
1407         struct bch_dev *ca = NULL;
1408         struct bkey hole;
1409         struct bkey_s_c k;
1410         int ret = 0;
1411
1412         bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc, POS_MIN,
1413                              BTREE_ITER_prefetch);
1414         bch2_trans_iter_init(trans, &discard_iter, BTREE_ID_need_discard, POS_MIN,
1415                              BTREE_ITER_prefetch);
1416         bch2_trans_iter_init(trans, &freespace_iter, BTREE_ID_freespace, POS_MIN,
1417                              BTREE_ITER_prefetch);
1418         bch2_trans_iter_init(trans, &bucket_gens_iter, BTREE_ID_bucket_gens, POS_MIN,
1419                              BTREE_ITER_prefetch);
1420
1421         while (1) {
1422                 struct bpos next;
1423
1424                 bch2_trans_begin(trans);
1425
1426                 k = bch2_get_key_or_real_bucket_hole(&iter, &ca, &hole);
1427                 ret = bkey_err(k);
1428                 if (ret)
1429                         goto bkey_err;
1430
1431                 if (!k.k)
1432                         break;
1433
1434                 if (k.k->type) {
1435                         next = bpos_nosnap_successor(k.k->p);
1436
1437                         ret = bch2_check_alloc_key(trans,
1438                                                    k, &iter,
1439                                                    &discard_iter,
1440                                                    &freespace_iter,
1441                                                    &bucket_gens_iter);
1442                         if (ret)
1443                                 goto bkey_err;
1444                 } else {
1445                         next = k.k->p;
1446
1447                         ret = bch2_check_alloc_hole_freespace(trans, ca,
1448                                                     bkey_start_pos(k.k),
1449                                                     &next,
1450                                                     &freespace_iter) ?:
1451                                 bch2_check_alloc_hole_bucket_gens(trans,
1452                                                     bkey_start_pos(k.k),
1453                                                     &next,
1454                                                     &bucket_gens_iter);
1455                         if (ret)
1456                                 goto bkey_err;
1457                 }
1458
1459                 ret = bch2_trans_commit(trans, NULL, NULL,
1460                                         BCH_TRANS_COMMIT_no_enospc);
1461                 if (ret)
1462                         goto bkey_err;
1463
1464                 bch2_btree_iter_set_pos(&iter, next);
1465 bkey_err:
1466                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
1467                         continue;
1468                 if (ret)
1469                         break;
1470         }
1471         bch2_trans_iter_exit(trans, &bucket_gens_iter);
1472         bch2_trans_iter_exit(trans, &freespace_iter);
1473         bch2_trans_iter_exit(trans, &discard_iter);
1474         bch2_trans_iter_exit(trans, &iter);
1475         bch2_dev_put(ca);
1476         ca = NULL;
1477
1478         if (ret < 0)
1479                 goto err;
1480
1481         ret = for_each_btree_key(trans, iter,
1482                         BTREE_ID_need_discard, POS_MIN,
1483                         BTREE_ITER_prefetch, k,
1484                 bch2_check_discard_freespace_key(trans, &iter));
1485         if (ret)
1486                 goto err;
1487
1488         bch2_trans_iter_init(trans, &iter, BTREE_ID_freespace, POS_MIN,
1489                              BTREE_ITER_prefetch);
1490         while (1) {
1491                 bch2_trans_begin(trans);
1492                 k = bch2_btree_iter_peek(&iter);
1493                 if (!k.k)
1494                         break;
1495
1496                 ret = bkey_err(k) ?:
1497                         bch2_check_discard_freespace_key(trans, &iter);
1498                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) {
1499                         ret = 0;
1500                         continue;
1501                 }
1502                 if (ret) {
1503                         struct printbuf buf = PRINTBUF;
1504                         bch2_bkey_val_to_text(&buf, c, k);
1505
1506                         bch_err(c, "while checking %s", buf.buf);
1507                         printbuf_exit(&buf);
1508                         break;
1509                 }
1510
1511                 bch2_btree_iter_set_pos(&iter, bpos_nosnap_successor(iter.pos));
1512         }
1513         bch2_trans_iter_exit(trans, &iter);
1514         if (ret)
1515                 goto err;
1516
1517         ret = for_each_btree_key_commit(trans, iter,
1518                         BTREE_ID_bucket_gens, POS_MIN,
1519                         BTREE_ITER_prefetch, k,
1520                         NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
1521                 bch2_check_bucket_gens_key(trans, &iter, k));
1522 err:
1523         bch2_trans_put(trans);
1524         bch_err_fn(c, ret);
1525         return ret;
1526 }
1527
1528 static int bch2_check_alloc_to_lru_ref(struct btree_trans *trans,
1529                                        struct btree_iter *alloc_iter)
1530 {
1531         struct bch_fs *c = trans->c;
1532         struct btree_iter lru_iter;
1533         struct bch_alloc_v4 a_convert;
1534         const struct bch_alloc_v4 *a;
1535         struct bkey_s_c alloc_k, lru_k;
1536         struct printbuf buf = PRINTBUF;
1537         int ret;
1538
1539         alloc_k = bch2_btree_iter_peek(alloc_iter);
1540         if (!alloc_k.k)
1541                 return 0;
1542
1543         ret = bkey_err(alloc_k);
1544         if (ret)
1545                 return ret;
1546
1547         a = bch2_alloc_to_v4(alloc_k, &a_convert);
1548
1549         if (a->data_type != BCH_DATA_cached)
1550                 return 0;
1551
1552         if (fsck_err_on(!a->io_time[READ], c,
1553                         alloc_key_cached_but_read_time_zero,
1554                         "cached bucket with read_time 0\n"
1555                         "  %s",
1556                 (printbuf_reset(&buf),
1557                  bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
1558                 struct bkey_i_alloc_v4 *a_mut =
1559                         bch2_alloc_to_v4_mut(trans, alloc_k);
1560                 ret = PTR_ERR_OR_ZERO(a_mut);
1561                 if (ret)
1562                         goto err;
1563
1564                 a_mut->v.io_time[READ] = atomic64_read(&c->io_clock[READ].now);
1565                 ret = bch2_trans_update(trans, alloc_iter,
1566                                         &a_mut->k_i, BTREE_TRIGGER_norun);
1567                 if (ret)
1568                         goto err;
1569
1570                 a = &a_mut->v;
1571         }
1572
1573         lru_k = bch2_bkey_get_iter(trans, &lru_iter, BTREE_ID_lru,
1574                              lru_pos(alloc_k.k->p.inode,
1575                                      bucket_to_u64(alloc_k.k->p),
1576                                      a->io_time[READ]), 0);
1577         ret = bkey_err(lru_k);
1578         if (ret)
1579                 return ret;
1580
1581         if (fsck_err_on(lru_k.k->type != KEY_TYPE_set, c,
1582                         alloc_key_to_missing_lru_entry,
1583                         "missing lru entry\n"
1584                         "  %s",
1585                         (printbuf_reset(&buf),
1586                          bch2_bkey_val_to_text(&buf, c, alloc_k), buf.buf))) {
1587                 ret = bch2_lru_set(trans,
1588                                    alloc_k.k->p.inode,
1589                                    bucket_to_u64(alloc_k.k->p),
1590                                    a->io_time[READ]);
1591                 if (ret)
1592                         goto err;
1593         }
1594 err:
1595 fsck_err:
1596         bch2_trans_iter_exit(trans, &lru_iter);
1597         printbuf_exit(&buf);
1598         return ret;
1599 }
1600
1601 int bch2_check_alloc_to_lru_refs(struct bch_fs *c)
1602 {
1603         int ret = bch2_trans_run(c,
1604                 for_each_btree_key_commit(trans, iter, BTREE_ID_alloc,
1605                                 POS_MIN, BTREE_ITER_prefetch, k,
1606                                 NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
1607                         bch2_check_alloc_to_lru_ref(trans, &iter)));
1608         bch_err_fn(c, ret);
1609         return ret;
1610 }
1611
1612 static int discard_in_flight_add(struct bch_fs *c, struct bpos bucket)
1613 {
1614         int ret;
1615
1616         mutex_lock(&c->discard_buckets_in_flight_lock);
1617         darray_for_each(c->discard_buckets_in_flight, i)
1618                 if (bkey_eq(*i, bucket)) {
1619                         ret = -EEXIST;
1620                         goto out;
1621                 }
1622
1623         ret = darray_push(&c->discard_buckets_in_flight, bucket);
1624 out:
1625         mutex_unlock(&c->discard_buckets_in_flight_lock);
1626         return ret;
1627 }
1628
1629 static void discard_in_flight_remove(struct bch_fs *c, struct bpos bucket)
1630 {
1631         mutex_lock(&c->discard_buckets_in_flight_lock);
1632         darray_for_each(c->discard_buckets_in_flight, i)
1633                 if (bkey_eq(*i, bucket)) {
1634                         darray_remove_item(&c->discard_buckets_in_flight, i);
1635                         goto found;
1636                 }
1637         BUG();
1638 found:
1639         mutex_unlock(&c->discard_buckets_in_flight_lock);
1640 }
1641
1642 struct discard_buckets_state {
1643         u64             seen;
1644         u64             open;
1645         u64             need_journal_commit;
1646         u64             discarded;
1647         struct bch_dev  *ca;
1648         u64             need_journal_commit_this_dev;
1649 };
1650
1651 static void discard_buckets_next_dev(struct bch_fs *c, struct discard_buckets_state *s, struct bch_dev *ca)
1652 {
1653         if (s->ca == ca)
1654                 return;
1655
1656         if (s->ca && s->need_journal_commit_this_dev >
1657             bch2_dev_usage_read(s->ca).d[BCH_DATA_free].buckets)
1658                 bch2_journal_flush_async(&c->journal, NULL);
1659
1660         if (s->ca)
1661                 percpu_ref_put(&s->ca->io_ref);
1662         s->ca = ca;
1663         s->need_journal_commit_this_dev = 0;
1664 }
1665
1666 static int bch2_discard_one_bucket(struct btree_trans *trans,
1667                                    struct btree_iter *need_discard_iter,
1668                                    struct bpos *discard_pos_done,
1669                                    struct discard_buckets_state *s)
1670 {
1671         struct bch_fs *c = trans->c;
1672         struct bpos pos = need_discard_iter->pos;
1673         struct btree_iter iter = { NULL };
1674         struct bkey_s_c k;
1675         struct bkey_i_alloc_v4 *a;
1676         struct printbuf buf = PRINTBUF;
1677         bool discard_locked = false;
1678         int ret = 0;
1679
1680         struct bch_dev *ca = s->ca && s->ca->dev_idx == pos.inode
1681                 ? s->ca
1682                 : bch2_dev_get_ioref(c, pos.inode, WRITE);
1683         if (!ca) {
1684                 bch2_btree_iter_set_pos(need_discard_iter, POS(pos.inode + 1, 0));
1685                 return 0;
1686         }
1687
1688         discard_buckets_next_dev(c, s, ca);
1689
1690         if (bch2_bucket_is_open_safe(c, pos.inode, pos.offset)) {
1691                 s->open++;
1692                 goto out;
1693         }
1694
1695         if (bch2_bucket_needs_journal_commit(&c->buckets_waiting_for_journal,
1696                         c->journal.flushed_seq_ondisk,
1697                         pos.inode, pos.offset)) {
1698                 s->need_journal_commit++;
1699                 s->need_journal_commit_this_dev++;
1700                 goto out;
1701         }
1702
1703         k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_alloc,
1704                                need_discard_iter->pos,
1705                                BTREE_ITER_cached);
1706         ret = bkey_err(k);
1707         if (ret)
1708                 goto out;
1709
1710         a = bch2_alloc_to_v4_mut(trans, k);
1711         ret = PTR_ERR_OR_ZERO(a);
1712         if (ret)
1713                 goto out;
1714
1715         if (bch2_bucket_sectors_total(a->v)) {
1716                 if (bch2_trans_inconsistent_on(c->curr_recovery_pass > BCH_RECOVERY_PASS_check_alloc_info,
1717                                                trans, "attempting to discard bucket with dirty data\n%s",
1718                                                (bch2_bkey_val_to_text(&buf, c, k), buf.buf)))
1719                         ret = -EIO;
1720                 goto out;
1721         }
1722
1723         if (a->v.data_type != BCH_DATA_need_discard) {
1724                 if (data_type_is_empty(a->v.data_type) &&
1725                     BCH_ALLOC_V4_NEED_INC_GEN(&a->v)) {
1726                         a->v.gen++;
1727                         SET_BCH_ALLOC_V4_NEED_INC_GEN(&a->v, false);
1728                         goto write;
1729                 }
1730
1731                 if (bch2_trans_inconsistent_on(c->curr_recovery_pass > BCH_RECOVERY_PASS_check_alloc_info,
1732                                                trans, "bucket incorrectly set in need_discard btree\n"
1733                                                "%s",
1734                                                (bch2_bkey_val_to_text(&buf, c, k), buf.buf)))
1735                         ret = -EIO;
1736                 goto out;
1737         }
1738
1739         if (a->v.journal_seq > c->journal.flushed_seq_ondisk) {
1740                 if (bch2_trans_inconsistent_on(c->curr_recovery_pass > BCH_RECOVERY_PASS_check_alloc_info,
1741                                                trans, "clearing need_discard but journal_seq %llu > flushed_seq %llu\n%s",
1742                                                a->v.journal_seq,
1743                                                c->journal.flushed_seq_ondisk,
1744                                                (bch2_bkey_val_to_text(&buf, c, k), buf.buf)))
1745                         ret = -EIO;
1746                 goto out;
1747         }
1748
1749         if (discard_in_flight_add(c, SPOS(iter.pos.inode, iter.pos.offset, true)))
1750                 goto out;
1751
1752         discard_locked = true;
1753
1754         if (!bkey_eq(*discard_pos_done, iter.pos) &&
1755             ca->mi.discard && !c->opts.nochanges) {
1756                 /*
1757                  * This works without any other locks because this is the only
1758                  * thread that removes items from the need_discard tree
1759                  */
1760                 bch2_trans_unlock_long(trans);
1761                 blkdev_issue_discard(ca->disk_sb.bdev,
1762                                      k.k->p.offset * ca->mi.bucket_size,
1763                                      ca->mi.bucket_size,
1764                                      GFP_KERNEL);
1765                 *discard_pos_done = iter.pos;
1766
1767                 ret = bch2_trans_relock_notrace(trans);
1768                 if (ret)
1769                         goto out;
1770         }
1771
1772         SET_BCH_ALLOC_V4_NEED_DISCARD(&a->v, false);
1773         alloc_data_type_set(&a->v, a->v.data_type);
1774 write:
1775         ret =   bch2_trans_update(trans, &iter, &a->k_i, 0) ?:
1776                 bch2_trans_commit(trans, NULL, NULL,
1777                                   BCH_WATERMARK_btree|
1778                                   BCH_TRANS_COMMIT_no_enospc);
1779         if (ret)
1780                 goto out;
1781
1782         count_event(c, bucket_discard);
1783         s->discarded++;
1784 out:
1785         if (discard_locked)
1786                 discard_in_flight_remove(c, iter.pos);
1787         s->seen++;
1788         bch2_trans_iter_exit(trans, &iter);
1789         printbuf_exit(&buf);
1790         return ret;
1791 }
1792
1793 static void bch2_do_discards_work(struct work_struct *work)
1794 {
1795         struct bch_fs *c = container_of(work, struct bch_fs, discard_work);
1796         struct discard_buckets_state s = {};
1797         struct bpos discard_pos_done = POS_MAX;
1798         int ret;
1799
1800         /*
1801          * We're doing the commit in bch2_discard_one_bucket instead of using
1802          * for_each_btree_key_commit() so that we can increment counters after
1803          * successful commit:
1804          */
1805         ret = bch2_trans_run(c,
1806                 for_each_btree_key(trans, iter,
1807                                    BTREE_ID_need_discard, POS_MIN, 0, k,
1808                         bch2_discard_one_bucket(trans, &iter, &discard_pos_done, &s)));
1809
1810         discard_buckets_next_dev(c, &s, NULL);
1811
1812         trace_discard_buckets(c, s.seen, s.open, s.need_journal_commit, s.discarded,
1813                               bch2_err_str(ret));
1814
1815         bch2_write_ref_put(c, BCH_WRITE_REF_discard);
1816 }
1817
1818 void bch2_do_discards(struct bch_fs *c)
1819 {
1820         if (bch2_write_ref_tryget(c, BCH_WRITE_REF_discard) &&
1821             !queue_work(c->write_ref_wq, &c->discard_work))
1822                 bch2_write_ref_put(c, BCH_WRITE_REF_discard);
1823 }
1824
1825 static int bch2_clear_bucket_needs_discard(struct btree_trans *trans, struct bpos bucket)
1826 {
1827         struct btree_iter iter;
1828         bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc, bucket, BTREE_ITER_intent);
1829         struct bkey_s_c k = bch2_btree_iter_peek_slot(&iter);
1830         int ret = bkey_err(k);
1831         if (ret)
1832                 goto err;
1833
1834         struct bkey_i_alloc_v4 *a = bch2_alloc_to_v4_mut(trans, k);
1835         ret = PTR_ERR_OR_ZERO(a);
1836         if (ret)
1837                 goto err;
1838
1839         BUG_ON(a->v.dirty_sectors);
1840         SET_BCH_ALLOC_V4_NEED_DISCARD(&a->v, false);
1841         alloc_data_type_set(&a->v, a->v.data_type);
1842
1843         ret = bch2_trans_update(trans, &iter, &a->k_i, 0);
1844 err:
1845         bch2_trans_iter_exit(trans, &iter);
1846         return ret;
1847 }
1848
1849 static void bch2_do_discards_fast_work(struct work_struct *work)
1850 {
1851         struct bch_fs *c = container_of(work, struct bch_fs, discard_fast_work);
1852
1853         while (1) {
1854                 bool got_bucket = false;
1855                 struct bpos bucket;
1856                 struct bch_dev *ca;
1857
1858                 mutex_lock(&c->discard_buckets_in_flight_lock);
1859                 darray_for_each(c->discard_buckets_in_flight, i) {
1860                         if (i->snapshot)
1861                                 continue;
1862
1863                         ca = bch2_dev_get_ioref(c, i->inode, WRITE);
1864                         if (!ca) {
1865                                 darray_remove_item(&c->discard_buckets_in_flight, i);
1866                                 continue;
1867                         }
1868
1869                         got_bucket = true;
1870                         bucket = *i;
1871                         i->snapshot = true;
1872                         break;
1873                 }
1874                 mutex_unlock(&c->discard_buckets_in_flight_lock);
1875
1876                 if (!got_bucket)
1877                         break;
1878
1879                 if (ca->mi.discard && !c->opts.nochanges)
1880                         blkdev_issue_discard(ca->disk_sb.bdev,
1881                                              bucket.offset * ca->mi.bucket_size,
1882                                              ca->mi.bucket_size,
1883                                              GFP_KERNEL);
1884
1885                 int ret = bch2_trans_do(c, NULL, NULL,
1886                                         BCH_WATERMARK_btree|
1887                                         BCH_TRANS_COMMIT_no_enospc,
1888                                         bch2_clear_bucket_needs_discard(trans, bucket));
1889                 bch_err_fn(c, ret);
1890
1891                 percpu_ref_put(&ca->io_ref);
1892                 discard_in_flight_remove(c, bucket);
1893
1894                 if (ret)
1895                         break;
1896         }
1897
1898         bch2_write_ref_put(c, BCH_WRITE_REF_discard_fast);
1899 }
1900
1901 static void bch2_discard_one_bucket_fast(struct bch_fs *c, struct bpos bucket)
1902 {
1903         rcu_read_lock();
1904         struct bch_dev *ca = bch2_dev_rcu(c, bucket.inode);
1905         bool dead = !ca || percpu_ref_is_dying(&ca->io_ref);
1906         rcu_read_unlock();
1907
1908         if (!dead &&
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 bkey_i_alloc_v4 *a = NULL;
1922         struct printbuf buf = PRINTBUF;
1923         struct bpos bucket = u64_to_bucket(lru_k.k->p.offset);
1924         unsigned cached_sectors;
1925         int ret = 0;
1926
1927         if (*nr_to_invalidate <= 0)
1928                 return 1;
1929
1930         if (!bch2_dev_bucket_exists(c, bucket)) {
1931                 prt_str(&buf, "lru entry points to invalid bucket");
1932                 goto err;
1933         }
1934
1935         if (bch2_bucket_is_open_safe(c, bucket.inode, bucket.offset))
1936                 return 0;
1937
1938         a = bch2_trans_start_alloc_update(trans, bucket);
1939         ret = PTR_ERR_OR_ZERO(a);
1940         if (ret)
1941                 goto out;
1942
1943         /* We expect harmless races here due to the btree write buffer: */
1944         if (lru_pos_time(lru_iter->pos) != alloc_lru_idx_read(a->v))
1945                 goto out;
1946
1947         BUG_ON(a->v.data_type != BCH_DATA_cached);
1948         BUG_ON(a->v.dirty_sectors);
1949
1950         if (!a->v.cached_sectors)
1951                 bch_err(c, "invalidating empty bucket, confused");
1952
1953         cached_sectors = a->v.cached_sectors;
1954
1955         SET_BCH_ALLOC_V4_NEED_INC_GEN(&a->v, false);
1956         a->v.gen++;
1957         a->v.data_type          = 0;
1958         a->v.dirty_sectors      = 0;
1959         a->v.cached_sectors     = 0;
1960         a->v.io_time[READ]      = atomic64_read(&c->io_clock[READ].now);
1961         a->v.io_time[WRITE]     = atomic64_read(&c->io_clock[WRITE].now);
1962
1963         ret = bch2_trans_commit(trans, NULL, NULL,
1964                                 BCH_WATERMARK_btree|
1965                                 BCH_TRANS_COMMIT_no_enospc);
1966         if (ret)
1967                 goto out;
1968
1969         trace_and_count(c, bucket_invalidate, c, bucket.inode, bucket.offset, cached_sectors);
1970         --*nr_to_invalidate;
1971 out:
1972         printbuf_exit(&buf);
1973         return ret;
1974 err:
1975         prt_str(&buf, "\n  lru key: ");
1976         bch2_bkey_val_to_text(&buf, c, lru_k);
1977
1978         prt_str(&buf, "\n  lru entry: ");
1979         bch2_lru_pos_to_text(&buf, lru_iter->pos);
1980
1981         prt_str(&buf, "\n  alloc key: ");
1982         if (!a)
1983                 bch2_bpos_to_text(&buf, bucket);
1984         else
1985                 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&a->k_i));
1986
1987         bch_err(c, "%s", buf.buf);
1988         if (c->curr_recovery_pass > BCH_RECOVERY_PASS_check_lrus) {
1989                 bch2_inconsistent_error(c);
1990                 ret = -EINVAL;
1991         }
1992
1993         goto out;
1994 }
1995
1996 static void bch2_do_invalidates_work(struct work_struct *work)
1997 {
1998         struct bch_fs *c = container_of(work, struct bch_fs, invalidate_work);
1999         struct btree_trans *trans = bch2_trans_get(c);
2000         int ret = 0;
2001
2002         ret = bch2_btree_write_buffer_tryflush(trans);
2003         if (ret)
2004                 goto err;
2005
2006         for_each_member_device(c, ca) {
2007                 s64 nr_to_invalidate =
2008                         should_invalidate_buckets(ca, bch2_dev_usage_read(ca));
2009
2010                 ret = for_each_btree_key_upto(trans, iter, BTREE_ID_lru,
2011                                 lru_pos(ca->dev_idx, 0, 0),
2012                                 lru_pos(ca->dev_idx, U64_MAX, LRU_TIME_MAX),
2013                                 BTREE_ITER_intent, k,
2014                         invalidate_one_bucket(trans, &iter, k, &nr_to_invalidate));
2015
2016                 if (ret < 0) {
2017                         bch2_dev_put(ca);
2018                         break;
2019                 }
2020         }
2021 err:
2022         bch2_trans_put(trans);
2023         bch2_write_ref_put(c, BCH_WRITE_REF_invalidate);
2024 }
2025
2026 void bch2_do_invalidates(struct bch_fs *c)
2027 {
2028         if (bch2_write_ref_tryget(c, BCH_WRITE_REF_invalidate) &&
2029             !queue_work(c->write_ref_wq, &c->invalidate_work))
2030                 bch2_write_ref_put(c, BCH_WRITE_REF_invalidate);
2031 }
2032
2033 int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca,
2034                             u64 bucket_start, u64 bucket_end)
2035 {
2036         struct btree_trans *trans = bch2_trans_get(c);
2037         struct btree_iter iter;
2038         struct bkey_s_c k;
2039         struct bkey hole;
2040         struct bpos end = POS(ca->dev_idx, bucket_end);
2041         struct bch_member *m;
2042         unsigned long last_updated = jiffies;
2043         int ret;
2044
2045         BUG_ON(bucket_start > bucket_end);
2046         BUG_ON(bucket_end > ca->mi.nbuckets);
2047
2048         bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc,
2049                 POS(ca->dev_idx, max_t(u64, ca->mi.first_bucket, bucket_start)),
2050                 BTREE_ITER_prefetch);
2051         /*
2052          * Scan the alloc btree for every bucket on @ca, and add buckets to the
2053          * freespace/need_discard/need_gc_gens btrees as needed:
2054          */
2055         while (1) {
2056                 if (last_updated + HZ * 10 < jiffies) {
2057                         bch_info(ca, "%s: currently at %llu/%llu",
2058                                  __func__, iter.pos.offset, ca->mi.nbuckets);
2059                         last_updated = jiffies;
2060                 }
2061
2062                 bch2_trans_begin(trans);
2063
2064                 if (bkey_ge(iter.pos, end)) {
2065                         ret = 0;
2066                         break;
2067                 }
2068
2069                 k = bch2_get_key_or_hole(&iter, end, &hole);
2070                 ret = bkey_err(k);
2071                 if (ret)
2072                         goto bkey_err;
2073
2074                 if (k.k->type) {
2075                         /*
2076                          * We process live keys in the alloc btree one at a
2077                          * time:
2078                          */
2079                         struct bch_alloc_v4 a_convert;
2080                         const struct bch_alloc_v4 *a = bch2_alloc_to_v4(k, &a_convert);
2081
2082                         ret =   bch2_bucket_do_index(trans, ca, k, a, true) ?:
2083                                 bch2_trans_commit(trans, NULL, NULL,
2084                                                   BCH_TRANS_COMMIT_no_enospc);
2085                         if (ret)
2086                                 goto bkey_err;
2087
2088                         bch2_btree_iter_advance(&iter);
2089                 } else {
2090                         struct bkey_i *freespace;
2091
2092                         freespace = bch2_trans_kmalloc(trans, sizeof(*freespace));
2093                         ret = PTR_ERR_OR_ZERO(freespace);
2094                         if (ret)
2095                                 goto bkey_err;
2096
2097                         bkey_init(&freespace->k);
2098                         freespace->k.type       = KEY_TYPE_set;
2099                         freespace->k.p          = k.k->p;
2100                         freespace->k.size       = k.k->size;
2101
2102                         ret = bch2_btree_insert_trans(trans, BTREE_ID_freespace, freespace, 0) ?:
2103                                 bch2_trans_commit(trans, NULL, NULL,
2104                                                   BCH_TRANS_COMMIT_no_enospc);
2105                         if (ret)
2106                                 goto bkey_err;
2107
2108                         bch2_btree_iter_set_pos(&iter, k.k->p);
2109                 }
2110 bkey_err:
2111                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
2112                         continue;
2113                 if (ret)
2114                         break;
2115         }
2116
2117         bch2_trans_iter_exit(trans, &iter);
2118         bch2_trans_put(trans);
2119
2120         if (ret < 0) {
2121                 bch_err_msg(ca, ret, "initializing free space");
2122                 return ret;
2123         }
2124
2125         mutex_lock(&c->sb_lock);
2126         m = bch2_members_v2_get_mut(c->disk_sb.sb, ca->dev_idx);
2127         SET_BCH_MEMBER_FREESPACE_INITIALIZED(m, true);
2128         mutex_unlock(&c->sb_lock);
2129
2130         return 0;
2131 }
2132
2133 int bch2_fs_freespace_init(struct bch_fs *c)
2134 {
2135         int ret = 0;
2136         bool doing_init = false;
2137
2138         /*
2139          * We can crash during the device add path, so we need to check this on
2140          * every mount:
2141          */
2142
2143         for_each_member_device(c, ca) {
2144                 if (ca->mi.freespace_initialized)
2145                         continue;
2146
2147                 if (!doing_init) {
2148                         bch_info(c, "initializing freespace");
2149                         doing_init = true;
2150                 }
2151
2152                 ret = bch2_dev_freespace_init(c, ca, 0, ca->mi.nbuckets);
2153                 if (ret) {
2154                         bch2_dev_put(ca);
2155                         bch_err_fn(c, ret);
2156                         return ret;
2157                 }
2158         }
2159
2160         if (doing_init) {
2161                 mutex_lock(&c->sb_lock);
2162                 bch2_write_super(c);
2163                 mutex_unlock(&c->sb_lock);
2164                 bch_verbose(c, "done initializing freespace");
2165         }
2166
2167         return 0;
2168 }
2169
2170 /* Bucket IO clocks: */
2171
2172 int bch2_bucket_io_time_reset(struct btree_trans *trans, unsigned dev,
2173                               size_t bucket_nr, int rw)
2174 {
2175         struct bch_fs *c = trans->c;
2176         struct btree_iter iter;
2177         struct bkey_i_alloc_v4 *a;
2178         u64 now;
2179         int ret = 0;
2180
2181         if (bch2_trans_relock(trans))
2182                 bch2_trans_begin(trans);
2183
2184         a = bch2_trans_start_alloc_update_noupdate(trans, &iter, POS(dev, bucket_nr));
2185         ret = PTR_ERR_OR_ZERO(a);
2186         if (ret)
2187                 return ret;
2188
2189         now = atomic64_read(&c->io_clock[rw].now);
2190         if (a->v.io_time[rw] == now)
2191                 goto out;
2192
2193         a->v.io_time[rw] = now;
2194
2195         ret   = bch2_trans_update(trans, &iter, &a->k_i, 0) ?:
2196                 bch2_trans_commit(trans, NULL, NULL, 0);
2197 out:
2198         bch2_trans_iter_exit(trans, &iter);
2199         return ret;
2200 }
2201
2202 /* Startup/shutdown (ro/rw): */
2203
2204 void bch2_recalc_capacity(struct bch_fs *c)
2205 {
2206         u64 capacity = 0, reserved_sectors = 0, gc_reserve;
2207         unsigned bucket_size_max = 0;
2208         unsigned long ra_pages = 0;
2209
2210         lockdep_assert_held(&c->state_lock);
2211
2212         for_each_online_member(c, ca) {
2213                 struct backing_dev_info *bdi = ca->disk_sb.bdev->bd_disk->bdi;
2214
2215                 ra_pages += bdi->ra_pages;
2216         }
2217
2218         bch2_set_ra_pages(c, ra_pages);
2219
2220         for_each_rw_member(c, ca) {
2221                 u64 dev_reserve = 0;
2222
2223                 /*
2224                  * We need to reserve buckets (from the number
2225                  * of currently available buckets) against
2226                  * foreground writes so that mainly copygc can
2227                  * make forward progress.
2228                  *
2229                  * We need enough to refill the various reserves
2230                  * from scratch - copygc will use its entire
2231                  * reserve all at once, then run against when
2232                  * its reserve is refilled (from the formerly
2233                  * available buckets).
2234                  *
2235                  * This reserve is just used when considering if
2236                  * allocations for foreground writes must wait -
2237                  * not -ENOSPC calculations.
2238                  */
2239
2240                 dev_reserve += ca->nr_btree_reserve * 2;
2241                 dev_reserve += ca->mi.nbuckets >> 6; /* copygc reserve */
2242
2243                 dev_reserve += 1;       /* btree write point */
2244                 dev_reserve += 1;       /* copygc write point */
2245                 dev_reserve += 1;       /* rebalance write point */
2246
2247                 dev_reserve *= ca->mi.bucket_size;
2248
2249                 capacity += bucket_to_sector(ca, ca->mi.nbuckets -
2250                                              ca->mi.first_bucket);
2251
2252                 reserved_sectors += dev_reserve * 2;
2253
2254                 bucket_size_max = max_t(unsigned, bucket_size_max,
2255                                         ca->mi.bucket_size);
2256         }
2257
2258         gc_reserve = c->opts.gc_reserve_bytes
2259                 ? c->opts.gc_reserve_bytes >> 9
2260                 : div64_u64(capacity * c->opts.gc_reserve_percent, 100);
2261
2262         reserved_sectors = max(gc_reserve, reserved_sectors);
2263
2264         reserved_sectors = min(reserved_sectors, capacity);
2265
2266         c->capacity = capacity - reserved_sectors;
2267
2268         c->bucket_size_max = bucket_size_max;
2269
2270         /* Wake up case someone was waiting for buckets */
2271         closure_wake_up(&c->freelist_wait);
2272 }
2273
2274 u64 bch2_min_rw_member_capacity(struct bch_fs *c)
2275 {
2276         u64 ret = U64_MAX;
2277
2278         for_each_rw_member(c, ca)
2279                 ret = min(ret, ca->mi.nbuckets * ca->mi.bucket_size);
2280         return ret;
2281 }
2282
2283 static bool bch2_dev_has_open_write_point(struct bch_fs *c, struct bch_dev *ca)
2284 {
2285         struct open_bucket *ob;
2286         bool ret = false;
2287
2288         for (ob = c->open_buckets;
2289              ob < c->open_buckets + ARRAY_SIZE(c->open_buckets);
2290              ob++) {
2291                 spin_lock(&ob->lock);
2292                 if (ob->valid && !ob->on_partial_list &&
2293                     ob->dev == ca->dev_idx)
2294                         ret = true;
2295                 spin_unlock(&ob->lock);
2296         }
2297
2298         return ret;
2299 }
2300
2301 /* device goes ro: */
2302 void bch2_dev_allocator_remove(struct bch_fs *c, struct bch_dev *ca)
2303 {
2304         unsigned i;
2305
2306         /* First, remove device from allocation groups: */
2307
2308         for (i = 0; i < ARRAY_SIZE(c->rw_devs); i++)
2309                 clear_bit(ca->dev_idx, c->rw_devs[i].d);
2310
2311         /*
2312          * Capacity is calculated based off of devices in allocation groups:
2313          */
2314         bch2_recalc_capacity(c);
2315
2316         bch2_open_buckets_stop(c, ca, false);
2317
2318         /*
2319          * Wake up threads that were blocked on allocation, so they can notice
2320          * the device can no longer be removed and the capacity has changed:
2321          */
2322         closure_wake_up(&c->freelist_wait);
2323
2324         /*
2325          * journal_res_get() can block waiting for free space in the journal -
2326          * it needs to notice there may not be devices to allocate from anymore:
2327          */
2328         wake_up(&c->journal.wait);
2329
2330         /* Now wait for any in flight writes: */
2331
2332         closure_wait_event(&c->open_buckets_wait,
2333                            !bch2_dev_has_open_write_point(c, ca));
2334 }
2335
2336 /* device goes rw: */
2337 void bch2_dev_allocator_add(struct bch_fs *c, struct bch_dev *ca)
2338 {
2339         unsigned i;
2340
2341         for (i = 0; i < ARRAY_SIZE(c->rw_devs); i++)
2342                 if (ca->mi.data_allowed & (1 << i))
2343                         set_bit(ca->dev_idx, c->rw_devs[i].d);
2344 }
2345
2346 void bch2_fs_allocator_background_exit(struct bch_fs *c)
2347 {
2348         darray_exit(&c->discard_buckets_in_flight);
2349 }
2350
2351 void bch2_fs_allocator_background_init(struct bch_fs *c)
2352 {
2353         spin_lock_init(&c->freelist_lock);
2354         mutex_init(&c->discard_buckets_in_flight_lock);
2355         INIT_WORK(&c->discard_work, bch2_do_discards_work);
2356         INIT_WORK(&c->discard_fast_work, bch2_do_discards_fast_work);
2357         INIT_WORK(&c->invalidate_work, bch2_do_invalidates_work);
2358 }