git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/extents.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2010 Kent Overstreet <kent.overstreet@gmail.com>
   4  *
   5  * Code for managing the extent btree and dynamically updating the writeback
   6  * dirty sector count.
   7  */
   8
   9 #include "bcachefs.h"
  10 #include "bkey_methods.h"
  11 #include "btree_gc.h"
  12 #include "btree_update.h"
  13 #include "btree_update_interior.h"
  14 #include "buckets.h"
  15 #include "checksum.h"
  16 #include "debug.h"
  17 #include "dirent.h"
  18 #include "disk_groups.h"
  19 #include "error.h"
  20 #include "extents.h"
  21 #include "inode.h"
  22 #include "journal.h"
  23 #include "replicas.h"
  24 #include "super.h"
  25 #include "super-io.h"
  26 #include "util.h"
  27 #include "xattr.h"
  28
  29 #include <trace/events/bcachefs.h>
  30
  31 unsigned bch2_bkey_nr_ptrs(struct bkey_s_c k)
  32 {
  33         struct bkey_ptrs_c p = bch2_bkey_ptrs_c(k);
  34         const struct bch_extent_ptr *ptr;
  35         unsigned nr_ptrs = 0;
  36
  37         bkey_for_each_ptr(p, ptr)
  38                 nr_ptrs++;
  39
  40         return nr_ptrs;
  41 }
  42
  43 unsigned bch2_bkey_nr_dirty_ptrs(struct bkey_s_c k)
  44 {
  45         unsigned nr_ptrs = 0;
  46
  47         switch (k.k->type) {
  48         case KEY_TYPE_btree_ptr:
  49         case KEY_TYPE_extent:
  50         case KEY_TYPE_reflink_v: {
  51                 struct bkey_ptrs_c p = bch2_bkey_ptrs_c(k);
  52                 const struct bch_extent_ptr *ptr;
  53
  54                 bkey_for_each_ptr(p, ptr)
  55                         nr_ptrs += !ptr->cached;
  56                 BUG_ON(!nr_ptrs);
  57                 break;
  58         }
  59         case KEY_TYPE_reservation:
  60                 nr_ptrs = bkey_s_c_to_reservation(k).v->nr_replicas;
  61                 break;
  62         }
  63
  64         return nr_ptrs;
  65 }
  66
  67 static unsigned bch2_extent_ptr_durability(struct bch_fs *c,
  68                                            struct extent_ptr_decoded p)
  69 {
  70         unsigned i, durability = 0;
  71         struct bch_dev *ca;
  72
  73         if (p.ptr.cached)
  74                 return 0;
  75
  76         ca = bch_dev_bkey_exists(c, p.ptr.dev);
  77
  78         if (ca->mi.state != BCH_MEMBER_STATE_FAILED)
  79                 durability = max_t(unsigned, durability, ca->mi.durability);
  80
  81         for (i = 0; i < p.ec_nr; i++) {
  82                 struct stripe *s =
  83                         genradix_ptr(&c->stripes[0], p.idx);
  84
  85                 if (WARN_ON(!s))
  86                         continue;
  87
  88                 durability = max_t(unsigned, durability, s->nr_redundant);
  89         }
  90
  91         return durability;
  92 }
  93
  94 unsigned bch2_bkey_durability(struct bch_fs *c, struct bkey_s_c k)
  95 {
  96         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
  97         const union bch_extent_entry *entry;
  98         struct extent_ptr_decoded p;
  99         unsigned durability = 0;
 100
 101         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 102                 durability += bch2_extent_ptr_durability(c, p);
 103
 104         return durability;
 105 }
 106
 107 static struct bch_dev_io_failures *dev_io_failures(struct bch_io_failures *f,
 108                                                    unsigned dev)
 109 {
 110         struct bch_dev_io_failures *i;
 111
 112         for (i = f->devs; i < f->devs + f->nr; i++)
 113                 if (i->dev == dev)
 114                         return i;
 115
 116         return NULL;
 117 }
 118
 119 void bch2_mark_io_failure(struct bch_io_failures *failed,
 120                           struct extent_ptr_decoded *p)
 121 {
 122         struct bch_dev_io_failures *f = dev_io_failures(failed, p->ptr.dev);
 123
 124         if (!f) {
 125                 BUG_ON(failed->nr >= ARRAY_SIZE(failed->devs));
 126
 127                 f = &failed->devs[failed->nr++];
 128                 f->dev          = p->ptr.dev;
 129                 f->idx          = p->idx;
 130                 f->nr_failed    = 1;
 131                 f->nr_retries   = 0;
 132         } else if (p->idx != f->idx) {
 133                 f->idx          = p->idx;
 134                 f->nr_failed    = 1;
 135                 f->nr_retries   = 0;
 136         } else {
 137                 f->nr_failed++;
 138         }
 139 }
 140
 141 /*
 142  * returns true if p1 is better than p2:
 143  */
 144 static inline bool ptr_better(struct bch_fs *c,
 145                               const struct extent_ptr_decoded p1,
 146                               const struct extent_ptr_decoded p2)
 147 {
 148         if (likely(!p1.idx && !p2.idx)) {
 149                 struct bch_dev *dev1 = bch_dev_bkey_exists(c, p1.ptr.dev);
 150                 struct bch_dev *dev2 = bch_dev_bkey_exists(c, p2.ptr.dev);
 151
 152                 u64 l1 = atomic64_read(&dev1->cur_latency[READ]);
 153                 u64 l2 = atomic64_read(&dev2->cur_latency[READ]);
 154
 155                 /* Pick at random, biased in favor of the faster device: */
 156
 157                 return bch2_rand_range(l1 + l2) > l1;
 158         }
 159
 160         if (force_reconstruct_read(c))
 161                 return p1.idx > p2.idx;
 162
 163         return p1.idx < p2.idx;
 164 }
 165
 166 /*
 167  * This picks a non-stale pointer, preferably from a device other than @avoid.
 168  * Avoid can be NULL, meaning pick any. If there are no non-stale pointers to
 169  * other devices, it will still pick a pointer from avoid.
 170  */
 171 int bch2_bkey_pick_read_device(struct bch_fs *c, struct bkey_s_c k,
 172                                struct bch_io_failures *failed,
 173                                struct extent_ptr_decoded *pick)
 174 {
 175         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 176         const union bch_extent_entry *entry;
 177         struct extent_ptr_decoded p;
 178         struct bch_dev_io_failures *f;
 179         struct bch_dev *ca;
 180         int ret = 0;
 181
 182         if (k.k->type == KEY_TYPE_error)
 183                 return -EIO;
 184
 185         bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
 186                 ca = bch_dev_bkey_exists(c, p.ptr.dev);
 187
 188                 /*
 189                  * If there are any dirty pointers it's an error if we can't
 190                  * read:
 191                  */
 192                 if (!ret && !p.ptr.cached)
 193                         ret = -EIO;
 194
 195                 if (p.ptr.cached && ptr_stale(ca, &p.ptr))
 196                         continue;
 197
 198                 f = failed ? dev_io_failures(failed, p.ptr.dev) : NULL;
 199                 if (f)
 200                         p.idx = f->nr_failed < f->nr_retries
 201                                 ? f->idx
 202                                 : f->idx + 1;
 203
 204                 if (!p.idx &&
 205                     !bch2_dev_is_readable(ca))
 206                         p.idx++;
 207
 208                 if (force_reconstruct_read(c) &&
 209                     !p.idx && p.ec_nr)
 210                         p.idx++;
 211
 212                 if (p.idx >= p.ec_nr + 1)
 213                         continue;
 214
 215                 if (ret > 0 && !ptr_better(c, p, *pick))
 216                         continue;
 217
 218                 *pick = p;
 219                 ret = 1;
 220         }
 221
 222         return ret;
 223 }
 224
 225 void bch2_bkey_append_ptr(struct bkey_i *k,
 226                           struct bch_extent_ptr ptr)
 227 {
 228         EBUG_ON(bch2_bkey_has_device(bkey_i_to_s_c(k), ptr.dev));
 229
 230         switch (k->k.type) {
 231         case KEY_TYPE_btree_ptr:
 232         case KEY_TYPE_extent:
 233                 EBUG_ON(bkey_val_u64s(&k->k) >= BKEY_EXTENT_VAL_U64s_MAX);
 234
 235                 ptr.type = 1 << BCH_EXTENT_ENTRY_ptr;
 236
 237                 memcpy((void *) &k->v + bkey_val_bytes(&k->k),
 238                        &ptr,
 239                        sizeof(ptr));
 240                 k->u64s++;
 241                 break;
 242         default:
 243                 BUG();
 244         }
 245 }
 246
 247 void bch2_bkey_drop_device(struct bkey_s k, unsigned dev)
 248 {
 249         struct bch_extent_ptr *ptr;
 250
 251         bch2_bkey_drop_ptrs(k, ptr, ptr->dev == dev);
 252 }
 253
 254 const struct bch_extent_ptr *
 255 bch2_bkey_has_device(struct bkey_s_c k, unsigned dev)
 256 {
 257         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 258         const struct bch_extent_ptr *ptr;
 259
 260         bkey_for_each_ptr(ptrs, ptr)
 261                 if (ptr->dev == dev)
 262                         return ptr;
 263
 264         return NULL;
 265 }
 266
 267 bool bch2_bkey_has_target(struct bch_fs *c, struct bkey_s_c k, unsigned target)
 268 {
 269         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 270         const struct bch_extent_ptr *ptr;
 271
 272         bkey_for_each_ptr(ptrs, ptr)
 273                 if (bch2_dev_in_target(c, ptr->dev, target) &&
 274                     (!ptr->cached ||
 275                      !ptr_stale(bch_dev_bkey_exists(c, ptr->dev), ptr)))
 276                         return true;
 277
 278         return false;
 279 }
 280
 281 /* extent specific utility code */
 282
 283 const struct bch_extent_ptr *
 284 bch2_extent_has_device(struct bkey_s_c_extent e, unsigned dev)
 285 {
 286         const struct bch_extent_ptr *ptr;
 287
 288         extent_for_each_ptr(e, ptr)
 289                 if (ptr->dev == dev)
 290                         return ptr;
 291
 292         return NULL;
 293 }
 294
 295 const struct bch_extent_ptr *
 296 bch2_extent_has_group(struct bch_fs *c, struct bkey_s_c_extent e, unsigned group)
 297 {
 298         const struct bch_extent_ptr *ptr;
 299
 300         extent_for_each_ptr(e, ptr) {
 301                 struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
 302
 303                 if (ca->mi.group &&
 304                     ca->mi.group - 1 == group)
 305                         return ptr;
 306         }
 307
 308         return NULL;
 309 }
 310
 311 unsigned bch2_extent_is_compressed(struct bkey_s_c k)
 312 {
 313         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 314         const union bch_extent_entry *entry;
 315         struct extent_ptr_decoded p;
 316         unsigned ret = 0;
 317
 318         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 319                 if (!p.ptr.cached &&
 320                     p.crc.compression_type != BCH_COMPRESSION_NONE)
 321                         ret += p.crc.compressed_size;
 322
 323         return ret;
 324 }
 325
 326 bool bch2_bkey_matches_ptr(struct bch_fs *c, struct bkey_s_c k,
 327                            struct bch_extent_ptr m, u64 offset)
 328 {
 329         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 330         const union bch_extent_entry *entry;
 331         struct extent_ptr_decoded p;
 332
 333         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 334                 if (p.ptr.dev   == m.dev &&
 335                     p.ptr.gen   == m.gen &&
 336                     (s64) p.ptr.offset + p.crc.offset - bkey_start_offset(k.k) ==
 337                     (s64) m.offset  - offset)
 338                         return true;
 339
 340         return false;
 341 }
 342
 343 static union bch_extent_entry *extent_entry_prev(struct bkey_ptrs ptrs,
 344                                           union bch_extent_entry *entry)
 345 {
 346         union bch_extent_entry *i = ptrs.start;
 347
 348         if (i == entry)
 349                 return NULL;
 350
 351         while (extent_entry_next(i) != entry)
 352                 i = extent_entry_next(i);
 353         return i;
 354 }
 355
 356 union bch_extent_entry *bch2_bkey_drop_ptr(struct bkey_s k,
 357                                            struct bch_extent_ptr *ptr)
 358 {
 359         struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
 360         union bch_extent_entry *dst, *src, *prev;
 361         bool drop_crc = true;
 362
 363         EBUG_ON(ptr < &ptrs.start->ptr ||
 364                 ptr >= &ptrs.end->ptr);
 365         EBUG_ON(ptr->type != 1 << BCH_EXTENT_ENTRY_ptr);
 366
 367         src = extent_entry_next(to_entry(ptr));
 368         if (src != ptrs.end &&
 369             !extent_entry_is_crc(src))
 370                 drop_crc = false;
 371
 372         dst = to_entry(ptr);
 373         while ((prev = extent_entry_prev(ptrs, dst))) {
 374                 if (extent_entry_is_ptr(prev))
 375                         break;
 376
 377                 if (extent_entry_is_crc(prev)) {
 378                         if (drop_crc)
 379                                 dst = prev;
 380                         break;
 381                 }
 382
 383                 dst = prev;
 384         }
 385
 386         memmove_u64s_down(dst, src,
 387                           (u64 *) ptrs.end - (u64 *) src);
 388         k.k->u64s -= (u64 *) src - (u64 *) dst;
 389
 390         return dst;
 391 }
 392
 393 static inline bool can_narrow_crc(struct bch_extent_crc_unpacked u,
 394                                   struct bch_extent_crc_unpacked n)
 395 {
 396         return !u.compression_type &&
 397                 u.csum_type &&
 398                 u.uncompressed_size > u.live_size &&
 399                 bch2_csum_type_is_encryption(u.csum_type) ==
 400                 bch2_csum_type_is_encryption(n.csum_type);
 401 }
 402
 403 bool bch2_can_narrow_extent_crcs(struct bkey_s_c k,
 404                                  struct bch_extent_crc_unpacked n)
 405 {
 406         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 407         struct bch_extent_crc_unpacked crc;
 408         const union bch_extent_entry *i;
 409
 410         if (!n.csum_type)
 411                 return false;
 412
 413         bkey_for_each_crc(k.k, ptrs, crc, i)
 414                 if (can_narrow_crc(crc, n))
 415                         return true;
 416
 417         return false;
 418 }
 419
 420 /*
 421  * We're writing another replica for this extent, so while we've got the data in
 422  * memory we'll be computing a new checksum for the currently live data.
 423  *
 424  * If there are other replicas we aren't moving, and they are checksummed but
 425  * not compressed, we can modify them to point to only the data that is
 426  * currently live (so that readers won't have to bounce) while we've got the
 427  * checksum we need:
 428  */
 429 bool bch2_bkey_narrow_crcs(struct bkey_i *k, struct bch_extent_crc_unpacked n)
 430 {
 431         struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 432         struct bch_extent_crc_unpacked u;
 433         struct extent_ptr_decoded p;
 434         union bch_extent_entry *i;
 435         bool ret = false;
 436
 437         /* Find a checksum entry that covers only live data: */
 438         if (!n.csum_type) {
 439                 bkey_for_each_crc(&k->k, ptrs, u, i)
 440                         if (!u.compression_type &&
 441                             u.csum_type &&
 442                             u.live_size == u.uncompressed_size) {
 443                                 n = u;
 444                                 goto found;
 445                         }
 446                 return false;
 447         }
 448 found:
 449         BUG_ON(n.compression_type);
 450         BUG_ON(n.offset);
 451         BUG_ON(n.live_size != k->k.size);
 452
 453 restart_narrow_pointers:
 454         ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 455
 456         bkey_for_each_ptr_decode(&k->k, ptrs, p, i)
 457                 if (can_narrow_crc(p.crc, n)) {
 458                         bch2_bkey_drop_ptr(bkey_i_to_s(k), &i->ptr);
 459                         p.ptr.offset += p.crc.offset;
 460                         p.crc = n;
 461                         bch2_extent_ptr_decoded_append(k, &p);
 462                         ret = true;
 463                         goto restart_narrow_pointers;
 464                 }
 465
 466         return ret;
 467 }
 468
 469 /* returns true if not equal */
 470 static inline bool bch2_crc_unpacked_cmp(struct bch_extent_crc_unpacked l,
 471                                          struct bch_extent_crc_unpacked r)
 472 {
 473         return (l.csum_type             != r.csum_type ||
 474                 l.compression_type      != r.compression_type ||
 475                 l.compressed_size       != r.compressed_size ||
 476                 l.uncompressed_size     != r.uncompressed_size ||
 477                 l.offset                != r.offset ||
 478                 l.live_size             != r.live_size ||
 479                 l.nonce                 != r.nonce ||
 480                 bch2_crc_cmp(l.csum, r.csum));
 481 }
 482
 483 void bch2_ptr_swab(const struct bkey_format *f, struct bkey_packed *k)
 484 {
 485         union bch_extent_entry *entry;
 486         u64 *d = (u64 *) bkeyp_val(f, k);
 487         unsigned i;
 488
 489         for (i = 0; i < bkeyp_val_u64s(f, k); i++)
 490                 d[i] = swab64(d[i]);
 491
 492         for (entry = (union bch_extent_entry *) d;
 493              entry < (union bch_extent_entry *) (d + bkeyp_val_u64s(f, k));
 494              entry = extent_entry_next(entry)) {
 495                 switch (extent_entry_type(entry)) {
 496                 case BCH_EXTENT_ENTRY_ptr:
 497                         break;
 498                 case BCH_EXTENT_ENTRY_crc32:
 499                         entry->crc32.csum = swab32(entry->crc32.csum);
 500                         break;
 501                 case BCH_EXTENT_ENTRY_crc64:
 502                         entry->crc64.csum_hi = swab16(entry->crc64.csum_hi);
 503                         entry->crc64.csum_lo = swab64(entry->crc64.csum_lo);
 504                         break;
 505                 case BCH_EXTENT_ENTRY_crc128:
 506                         entry->crc128.csum.hi = (__force __le64)
 507                                 swab64((__force u64) entry->crc128.csum.hi);
 508                         entry->crc128.csum.lo = (__force __le64)
 509                                 swab64((__force u64) entry->crc128.csum.lo);
 510                         break;
 511                 case BCH_EXTENT_ENTRY_stripe_ptr:
 512                         break;
 513                 }
 514         }
 515 }
 516
 517 void bch2_bkey_ptrs_to_text(struct printbuf *out, struct bch_fs *c,
 518                             struct bkey_s_c k)
 519 {
 520         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 521         const union bch_extent_entry *entry;
 522         struct bch_extent_crc_unpacked crc;
 523         const struct bch_extent_ptr *ptr;
 524         const struct bch_extent_stripe_ptr *ec;
 525         struct bch_dev *ca;
 526         bool first = true;
 527
 528         bkey_extent_entry_for_each(ptrs, entry) {
 529                 if (!first)
 530                         pr_buf(out, " ");
 531
 532                 switch (__extent_entry_type(entry)) {
 533                 case BCH_EXTENT_ENTRY_ptr:
 534                         ptr = entry_to_ptr(entry);
 535                         ca = ptr->dev < c->sb.nr_devices && c->devs[ptr->dev]
 536                                 ? bch_dev_bkey_exists(c, ptr->dev)
 537                                 : NULL;
 538
 539                         pr_buf(out, "ptr: %u:%llu gen %u%s%s", ptr->dev,
 540                                (u64) ptr->offset, ptr->gen,
 541                                ptr->cached ? " cached" : "",
 542                                ca && ptr_stale(ca, ptr)
 543                                ? " stale" : "");
 544                         break;
 545                 case BCH_EXTENT_ENTRY_crc32:
 546                 case BCH_EXTENT_ENTRY_crc64:
 547                 case BCH_EXTENT_ENTRY_crc128:
 548                         crc = bch2_extent_crc_unpack(k.k, entry_to_crc(entry));
 549
 550                         pr_buf(out, "crc: c_size %u size %u offset %u nonce %u csum %u compress %u",
 551                                crc.compressed_size,
 552                                crc.uncompressed_size,
 553                                crc.offset, crc.nonce,
 554                                crc.csum_type,
 555                                crc.compression_type);
 556                         break;
 557                 case BCH_EXTENT_ENTRY_stripe_ptr:
 558                         ec = &entry->stripe_ptr;
 559
 560                         pr_buf(out, "ec: idx %llu block %u",
 561                                (u64) ec->idx, ec->block);
 562                         break;
 563                 default:
 564                         pr_buf(out, "(invalid extent entry %.16llx)", *((u64 *) entry));
 565                         return;
 566                 }
 567
 568                 first = false;
 569         }
 570 }
 571
 572 static const char *extent_ptr_invalid(const struct bch_fs *c,
 573                                       struct bkey_s_c k,
 574                                       const struct bch_extent_ptr *ptr,
 575                                       unsigned size_ondisk,
 576                                       bool metadata)
 577 {
 578         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 579         const struct bch_extent_ptr *ptr2;
 580         struct bch_dev *ca;
 581
 582         if (!bch2_dev_exists2(c, ptr->dev))
 583                 return "pointer to invalid device";
 584
 585         ca = bch_dev_bkey_exists(c, ptr->dev);
 586         if (!ca)
 587                 return "pointer to invalid device";
 588
 589         bkey_for_each_ptr(ptrs, ptr2)
 590                 if (ptr != ptr2 && ptr->dev == ptr2->dev)
 591                         return "multiple pointers to same device";
 592
 593         if (ptr->offset + size_ondisk > bucket_to_sector(ca, ca->mi.nbuckets))
 594                 return "offset past end of device";
 595
 596         if (ptr->offset < bucket_to_sector(ca, ca->mi.first_bucket))
 597                 return "offset before first bucket";
 598
 599         if (bucket_remainder(ca, ptr->offset) +
 600             size_ondisk > ca->mi.bucket_size)
 601                 return "spans multiple buckets";
 602
 603         return NULL;
 604 }
 605
 606 const char *bch2_bkey_ptrs_invalid(const struct bch_fs *c, struct bkey_s_c k)
 607 {
 608         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 609         const union bch_extent_entry *entry;
 610         struct bch_extent_crc_unpacked crc;
 611         unsigned size_ondisk = k.k->size;
 612         const char *reason;
 613         unsigned nonce = UINT_MAX;
 614
 615         if (k.k->type == KEY_TYPE_btree_ptr)
 616                 size_ondisk = c->opts.btree_node_size;
 617
 618         bkey_extent_entry_for_each(ptrs, entry) {
 619                 if (__extent_entry_type(entry) >= BCH_EXTENT_ENTRY_MAX)
 620                         return "invalid extent entry type";
 621
 622                 if (k.k->type == KEY_TYPE_btree_ptr &&
 623                     !extent_entry_is_ptr(entry))
 624                         return "has non ptr field";
 625
 626                 switch (extent_entry_type(entry)) {
 627                 case BCH_EXTENT_ENTRY_ptr:
 628                         reason = extent_ptr_invalid(c, k, &entry->ptr,
 629                                                     size_ondisk, false);
 630                         if (reason)
 631                                 return reason;
 632                         break;
 633                 case BCH_EXTENT_ENTRY_crc32:
 634                 case BCH_EXTENT_ENTRY_crc64:
 635                 case BCH_EXTENT_ENTRY_crc128:
 636                         crc = bch2_extent_crc_unpack(k.k, entry_to_crc(entry));
 637
 638                         if (crc.offset + crc.live_size >
 639                             crc.uncompressed_size)
 640                                 return "checksum offset + key size > uncompressed size";
 641
 642                         size_ondisk = crc.compressed_size;
 643
 644                         if (!bch2_checksum_type_valid(c, crc.csum_type))
 645                                 return "invalid checksum type";
 646
 647                         if (crc.compression_type >= BCH_COMPRESSION_NR)
 648                                 return "invalid compression type";
 649
 650                         if (bch2_csum_type_is_encryption(crc.csum_type)) {
 651                                 if (nonce == UINT_MAX)
 652                                         nonce = crc.offset + crc.nonce;
 653                                 else if (nonce != crc.offset + crc.nonce)
 654                                         return "incorrect nonce";
 655                         }
 656                         break;
 657                 case BCH_EXTENT_ENTRY_stripe_ptr:
 658                         break;
 659                 }
 660         }
 661
 662         return NULL;
 663 }
 664
 665 /* Btree ptrs */
 666
 667 const char *bch2_btree_ptr_invalid(const struct bch_fs *c, struct bkey_s_c k)
 668 {
 669         if (bkey_val_u64s(k.k) > BKEY_BTREE_PTR_VAL_U64s_MAX)
 670                 return "value too big";
 671
 672         return bch2_bkey_ptrs_invalid(c, k);
 673 }
 674
 675 void bch2_btree_ptr_debugcheck(struct bch_fs *c, struct bkey_s_c k)
 676 {
 677         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 678         const struct bch_extent_ptr *ptr;
 679         const char *err;
 680         char buf[160];
 681         struct bucket_mark mark;
 682         struct bch_dev *ca;
 683
 684         bch2_fs_bug_on(!test_bit(BCH_FS_REBUILD_REPLICAS, &c->flags) &&
 685                        !bch2_bkey_replicas_marked(c, k, false), c,
 686                        "btree key bad (replicas not marked in superblock):\n%s",
 687                        (bch2_bkey_val_to_text(&PBUF(buf), c, k), buf));
 688
 689         if (!test_bit(BCH_FS_INITIAL_GC_DONE, &c->flags))
 690                 return;
 691
 692         bkey_for_each_ptr(ptrs, ptr) {
 693                 ca = bch_dev_bkey_exists(c, ptr->dev);
 694
 695                 mark = ptr_bucket_mark(ca, ptr);
 696
 697                 err = "stale";
 698                 if (gen_after(mark.gen, ptr->gen))
 699                         goto err;
 700
 701                 err = "inconsistent";
 702                 if (mark.data_type != BCH_DATA_BTREE ||
 703                     mark.dirty_sectors < c->opts.btree_node_size)
 704                         goto err;
 705         }
 706
 707         return;
 708 err:
 709         bch2_bkey_val_to_text(&PBUF(buf), c, k);
 710         bch2_fs_bug(c, "%s btree pointer %s: bucket %zi gen %i mark %08x",
 711                     err, buf, PTR_BUCKET_NR(ca, ptr),
 712                     mark.gen, (unsigned) mark.v.counter);
 713 }
 714
 715 void bch2_btree_ptr_to_text(struct printbuf *out, struct bch_fs *c,
 716                             struct bkey_s_c k)
 717 {
 718         bch2_bkey_ptrs_to_text(out, c, k);
 719 }
 720
 721 /* Extents */
 722
 723 void __bch2_cut_front(struct bpos where, struct bkey_s k)
 724 {
 725         u64 sub;
 726
 727         if (bkey_cmp(where, bkey_start_pos(k.k)) <= 0)
 728                 return;
 729
 730         EBUG_ON(bkey_cmp(where, k.k->p) > 0);
 731
 732         sub = where.offset - bkey_start_offset(k.k);
 733
 734         k.k->size -= sub;
 735
 736         if (!k.k->size)
 737                 k.k->type = KEY_TYPE_deleted;
 738
 739         switch (k.k->type) {
 740         case KEY_TYPE_deleted:
 741         case KEY_TYPE_discard:
 742         case KEY_TYPE_error:
 743         case KEY_TYPE_cookie:
 744                 break;
 745         case KEY_TYPE_extent:
 746         case KEY_TYPE_reflink_v: {
 747                 struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
 748                 union bch_extent_entry *entry;
 749                 bool seen_crc = false;
 750
 751                 bkey_extent_entry_for_each(ptrs, entry) {
 752                         switch (extent_entry_type(entry)) {
 753                         case BCH_EXTENT_ENTRY_ptr:
 754                                 if (!seen_crc)
 755                                         entry->ptr.offset += sub;
 756                                 break;
 757                         case BCH_EXTENT_ENTRY_crc32:
 758                                 entry->crc32.offset += sub;
 759                                 break;
 760                         case BCH_EXTENT_ENTRY_crc64:
 761                                 entry->crc64.offset += sub;
 762                                 break;
 763                         case BCH_EXTENT_ENTRY_crc128:
 764                                 entry->crc128.offset += sub;
 765                                 break;
 766                         case BCH_EXTENT_ENTRY_stripe_ptr:
 767                                 break;
 768                         }
 769
 770                         if (extent_entry_is_crc(entry))
 771                                 seen_crc = true;
 772                 }
 773
 774                 break;
 775         }
 776         case KEY_TYPE_reflink_p: {
 777                 struct bkey_s_reflink_p p = bkey_s_to_reflink_p(k);
 778
 779                 le64_add_cpu(&p.v->idx, sub);
 780                 break;
 781         }
 782         case KEY_TYPE_reservation:
 783                 break;
 784         default:
 785                 BUG();
 786         }
 787 }
 788
 789 bool bch2_cut_back(struct bpos where, struct bkey *k)
 790 {
 791         u64 len = 0;
 792
 793         if (bkey_cmp(where, k->p) >= 0)
 794                 return false;
 795
 796         EBUG_ON(bkey_cmp(where, bkey_start_pos(k)) < 0);
 797
 798         len = where.offset - bkey_start_offset(k);
 799
 800         k->p = where;
 801         k->size = len;
 802
 803         if (!len)
 804                 k->type = KEY_TYPE_deleted;
 805
 806         return true;
 807 }
 808
 809 static bool extent_i_save(struct btree *b, struct bkey_packed *dst,
 810                           struct bkey_i *src)
 811 {
 812         struct bkey_format *f = &b->format;
 813         struct bkey_i *dst_unpacked;
 814         struct bkey_packed tmp;
 815
 816         if ((dst_unpacked = packed_to_bkey(dst)))
 817                 dst_unpacked->k = src->k;
 818         else if (bch2_bkey_pack_key(&tmp, &src->k, f))
 819                 memcpy_u64s(dst, &tmp, f->key_u64s);
 820         else
 821                 return false;
 822
 823         memcpy_u64s(bkeyp_val(f, dst), &src->v, bkey_val_u64s(&src->k));
 824         return true;
 825 }
 826
 827 static bool bch2_extent_merge_inline(struct bch_fs *,
 828                                      struct btree_iter *,
 829                                      struct bkey_packed *,
 830                                      struct bkey_packed *,
 831                                      bool);
 832
 833 static void verify_extent_nonoverlapping(struct bch_fs *c,
 834                                          struct btree *b,
 835                                          struct btree_node_iter *_iter,
 836                                          struct bkey_i *insert)
 837 {
 838 #ifdef CONFIG_BCACHEFS_DEBUG
 839         struct btree_node_iter iter;
 840         struct bkey_packed *k;
 841         struct bkey uk;
 842
 843         if (!expensive_debug_checks(c))
 844                 return;
 845
 846         iter = *_iter;
 847         k = bch2_btree_node_iter_prev_filter(&iter, b, KEY_TYPE_discard);
 848         BUG_ON(k &&
 849                (uk = bkey_unpack_key(b, k),
 850                 bkey_cmp(uk.p, bkey_start_pos(&insert->k)) > 0));
 851
 852         iter = *_iter;
 853         k = bch2_btree_node_iter_peek_filter(&iter, b, KEY_TYPE_discard);
 854 #if 0
 855         BUG_ON(k &&
 856                (uk = bkey_unpack_key(b, k),
 857                 bkey_cmp(insert->k.p, bkey_start_pos(&uk))) > 0);
 858 #else
 859         if (k &&
 860             (uk = bkey_unpack_key(b, k),
 861              bkey_cmp(insert->k.p, bkey_start_pos(&uk))) > 0) {
 862                 char buf1[100];
 863                 char buf2[100];
 864
 865                 bch2_bkey_to_text(&PBUF(buf1), &insert->k);
 866                 bch2_bkey_to_text(&PBUF(buf2), &uk);
 867
 868                 bch2_dump_btree_node(b);
 869                 panic("insert > next :\n"
 870                       "insert %s\n"
 871                       "next   %s\n",
 872                       buf1, buf2);
 873         }
 874 #endif
 875
 876 #endif
 877 }
 878
 879 static void extent_bset_insert(struct bch_fs *c, struct btree_iter *iter,
 880                                struct bkey_i *insert)
 881 {
 882         struct btree_iter_level *l = &iter->l[0];
 883         struct btree_node_iter node_iter;
 884         struct bkey_packed *k;
 885
 886         BUG_ON(insert->k.u64s > bch_btree_keys_u64s_remaining(c, l->b));
 887
 888         EBUG_ON(bkey_deleted(&insert->k) || !insert->k.size);
 889         verify_extent_nonoverlapping(c, l->b, &l->iter, insert);
 890
 891         if (debug_check_bkeys(c))
 892                 bch2_bkey_debugcheck(c, l->b, bkey_i_to_s_c(insert));
 893
 894         node_iter = l->iter;
 895         k = bch2_btree_node_iter_prev_filter(&node_iter, l->b, KEY_TYPE_discard);
 896         if (k && !bkey_written(l->b, k) &&
 897             bch2_extent_merge_inline(c, iter, k, bkey_to_packed(insert), true))
 898                 return;
 899
 900         node_iter = l->iter;
 901         k = bch2_btree_node_iter_peek_filter(&node_iter, l->b, KEY_TYPE_discard);
 902         if (k && !bkey_written(l->b, k) &&
 903             bch2_extent_merge_inline(c, iter, bkey_to_packed(insert), k, false))
 904                 return;
 905
 906         /*
 907          * may have skipped past some deleted extents greater than the insert
 908          * key, before we got to a non deleted extent and knew we could bail out
 909          * rewind the iterator a bit if necessary:
 910          */
 911         node_iter = l->iter;
 912         while ((k = bch2_btree_node_iter_prev_all(&node_iter, l->b)) &&
 913                bkey_cmp_left_packed(l->b, k, &insert->k.p) > 0)
 914                 l->iter = node_iter;
 915
 916         k = bch2_btree_node_iter_bset_pos(&l->iter, l->b, bset_tree_last(l->b));
 917
 918         bch2_bset_insert(l->b, &l->iter, k, insert, 0);
 919         bch2_btree_node_iter_fix(iter, l->b, &l->iter, k, 0, k->u64s);
 920 }
 921
 922 static unsigned bch2_bkey_nr_alloc_ptrs(struct bkey_s_c k)
 923 {
 924         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 925         const union bch_extent_entry *entry;
 926         unsigned ret = 0;
 927
 928         bkey_extent_entry_for_each(ptrs, entry) {
 929                 switch (__extent_entry_type(entry)) {
 930                 case BCH_EXTENT_ENTRY_ptr:
 931                 case BCH_EXTENT_ENTRY_stripe_ptr:
 932                         ret++;
 933                 }
 934         }
 935
 936         return ret;
 937 }
 938
 939 static int count_iters_for_insert(struct btree_trans *trans,
 940                                   struct bkey_s_c k,
 941                                   unsigned offset,
 942                                   struct bpos *end,
 943                                   unsigned *nr_iters,
 944                                   unsigned max_iters,
 945                                   bool overwrite)
 946 {
 947         int ret = 0;
 948
 949         switch (k.k->type) {
 950         case KEY_TYPE_extent:
 951         case KEY_TYPE_reflink_v:
 952                 *nr_iters += bch2_bkey_nr_alloc_ptrs(k);
 953
 954                 if (*nr_iters >= max_iters) {
 955                         *end = bpos_min(*end, k.k->p);
 956                         ret = 1;
 957                 }
 958
 959                 break;
 960         case KEY_TYPE_reflink_p: {
 961                 struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
 962                 u64 idx = le64_to_cpu(p.v->idx);
 963                 unsigned sectors = end->offset - bkey_start_offset(p.k);
 964                 struct btree_iter *iter;
 965                 struct bkey_s_c r_k;
 966
 967                 for_each_btree_key(trans, iter,
 968                                    BTREE_ID_REFLINK, POS(0, idx + offset),
 969                                    BTREE_ITER_SLOTS, r_k, ret) {
 970                         if (bkey_cmp(bkey_start_pos(r_k.k),
 971                                      POS(0, idx + sectors)) >= 0)
 972                                 break;
 973
 974                         *nr_iters += 1;
 975
 976                         if (overwrite &&
 977                             r_k.k->type == KEY_TYPE_reflink_v) {
 978                                 struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(r_k);
 979
 980                                 if (le64_to_cpu(r.v->refcount) == 1)
 981                                         *nr_iters += bch2_bkey_nr_alloc_ptrs(r_k);
 982                         }
 983
 984                         /*
 985                          * if we're going to be deleting an entry from
 986                          * the reflink btree, need more iters...
 987                          */
 988
 989                         if (*nr_iters >= max_iters) {
 990                                 struct bpos pos = bkey_start_pos(k.k);
 991                                 pos.offset += r_k.k->p.offset - idx;
 992
 993                                 *end = bpos_min(*end, pos);
 994                                 ret = 1;
 995                                 break;
 996                         }
 997                 }
 998
 999                 bch2_trans_iter_put(trans, iter);
1000                 break;
1001         }
1002         }
1003
1004         return ret;
1005 }
1006
1007 #define EXTENT_ITERS_MAX        (BTREE_ITER_MAX / 3)
1008
1009 int bch2_extent_atomic_end(struct btree_iter *iter,
1010                            struct bkey_i *insert,
1011                            struct bpos *end)
1012 {
1013         struct btree_trans *trans = iter->trans;
1014         struct btree *b = iter->l[0].b;
1015         struct btree_node_iter  node_iter = iter->l[0].iter;
1016         struct bkey_packed      *_k;
1017         unsigned                nr_iters = 0;
1018         int ret;
1019
1020         BUG_ON(iter->uptodate > BTREE_ITER_NEED_PEEK);
1021         BUG_ON(bkey_cmp(bkey_start_pos(&insert->k), b->data->min_key) < 0);
1022
1023         *end = bpos_min(insert->k.p, b->key.k.p);
1024
1025         ret = count_iters_for_insert(trans, bkey_i_to_s_c(insert), 0, end,
1026                                      &nr_iters, EXTENT_ITERS_MAX / 2, false);
1027         if (ret < 0)
1028                 return ret;
1029
1030         while ((_k = bch2_btree_node_iter_peek_filter(&node_iter, b,
1031                                                       KEY_TYPE_discard))) {
1032                 struct bkey     unpacked;
1033                 struct bkey_s_c k = bkey_disassemble(b, _k, &unpacked);
1034                 unsigned offset = 0;
1035
1036                 if (bkey_cmp(bkey_start_pos(k.k), *end) >= 0)
1037                         break;
1038
1039                 if (bkey_cmp(bkey_start_pos(&insert->k),
1040                              bkey_start_pos(k.k)) > 0)
1041                         offset = bkey_start_offset(&insert->k) -
1042                                 bkey_start_offset(k.k);
1043
1044                 ret = count_iters_for_insert(trans, k, offset, end,
1045                                         &nr_iters, EXTENT_ITERS_MAX, true);
1046                 if (ret)
1047                         break;
1048
1049                 bch2_btree_node_iter_advance(&node_iter, b);
1050         }
1051
1052         return ret < 0 ? ret : 0;
1053 }
1054
1055 int bch2_extent_trim_atomic(struct bkey_i *k, struct btree_iter *iter)
1056 {
1057         struct bpos end;
1058         int ret;
1059
1060         ret = bch2_extent_atomic_end(iter, k, &end);
1061         if (ret)
1062                 return ret;
1063
1064         bch2_cut_back(end, &k->k);
1065         return 0;
1066 }
1067
1068 int bch2_extent_is_atomic(struct bkey_i *k, struct btree_iter *iter)
1069 {
1070         struct bpos end;
1071         int ret;
1072
1073         ret = bch2_extent_atomic_end(iter, k, &end);
1074         if (ret)
1075                 return ret;
1076
1077         return !bkey_cmp(end, k->k.p);
1078 }
1079
1080 enum btree_insert_ret
1081 bch2_extent_can_insert(struct btree_trans *trans,
1082                        struct btree_insert_entry *insert,
1083                        unsigned *u64s)
1084 {
1085         struct btree_iter_level *l = &insert->iter->l[0];
1086         struct btree_node_iter node_iter = l->iter;
1087         enum bch_extent_overlap overlap;
1088         struct bkey_packed *_k;
1089         struct bkey unpacked;
1090         struct bkey_s_c k;
1091         int sectors;
1092
1093         /*
1094          * We avoid creating whiteouts whenever possible when deleting, but
1095          * those optimizations mean we may potentially insert two whiteouts
1096          * instead of one (when we overlap with the front of one extent and the
1097          * back of another):
1098          */
1099         if (bkey_whiteout(&insert->k->k))
1100                 *u64s += BKEY_U64s;
1101
1102         _k = bch2_btree_node_iter_peek_filter(&node_iter, l->b,
1103                                               KEY_TYPE_discard);
1104         if (!_k)
1105                 return BTREE_INSERT_OK;
1106
1107         k = bkey_disassemble(l->b, _k, &unpacked);
1108
1109         overlap = bch2_extent_overlap(&insert->k->k, k.k);
1110
1111         /* account for having to split existing extent: */
1112         if (overlap == BCH_EXTENT_OVERLAP_MIDDLE)
1113                 *u64s += _k->u64s;
1114
1115         if (overlap == BCH_EXTENT_OVERLAP_MIDDLE &&
1116             (sectors = bch2_extent_is_compressed(k))) {
1117                 int flags = trans->flags & BTREE_INSERT_NOFAIL
1118                         ? BCH_DISK_RESERVATION_NOFAIL : 0;
1119
1120                 switch (bch2_disk_reservation_add(trans->c,
1121                                 trans->disk_res,
1122                                 sectors, flags)) {
1123                 case 0:
1124                         break;
1125                 case -ENOSPC:
1126                         return BTREE_INSERT_ENOSPC;
1127                 default:
1128                         BUG();
1129                 }
1130         }
1131
1132         return BTREE_INSERT_OK;
1133 }
1134
1135 static void
1136 extent_squash(struct bch_fs *c, struct btree_iter *iter,
1137               struct bkey_i *insert,
1138               struct bkey_packed *_k, struct bkey_s k,
1139               enum bch_extent_overlap overlap)
1140 {
1141         struct btree_iter_level *l = &iter->l[0];
1142
1143         switch (overlap) {
1144         case BCH_EXTENT_OVERLAP_FRONT:
1145                 /* insert overlaps with start of k: */
1146                 __bch2_cut_front(insert->k.p, k);
1147                 EBUG_ON(bkey_deleted(k.k));
1148                 extent_save(l->b, _k, k.k);
1149                 bch2_btree_node_iter_fix(iter, l->b, &l->iter,
1150                                          _k, _k->u64s, _k->u64s);
1151                 break;
1152
1153         case BCH_EXTENT_OVERLAP_BACK:
1154                 /* insert overlaps with end of k: */
1155                 bch2_cut_back(bkey_start_pos(&insert->k), k.k);
1156                 EBUG_ON(bkey_deleted(k.k));
1157                 extent_save(l->b, _k, k.k);
1158
1159                 /*
1160                  * As the auxiliary tree is indexed by the end of the
1161                  * key and we've just changed the end, update the
1162                  * auxiliary tree.
1163                  */
1164                 bch2_bset_fix_invalidated_key(l->b, _k);
1165                 bch2_btree_node_iter_fix(iter, l->b, &l->iter,
1166                                          _k, _k->u64s, _k->u64s);
1167                 break;
1168
1169         case BCH_EXTENT_OVERLAP_ALL: {
1170                 /* The insert key completely covers k, invalidate k */
1171                 if (!bkey_whiteout(k.k))
1172                         btree_account_key_drop(l->b, _k);
1173
1174                 k.k->size = 0;
1175                 k.k->type = KEY_TYPE_deleted;
1176
1177                 if (_k >= btree_bset_last(l->b)->start) {
1178                         unsigned u64s = _k->u64s;
1179
1180                         bch2_bset_delete(l->b, _k, _k->u64s);
1181                         bch2_btree_node_iter_fix(iter, l->b, &l->iter,
1182                                                  _k, u64s, 0);
1183                 } else {
1184                         extent_save(l->b, _k, k.k);
1185                         bch2_btree_node_iter_fix(iter, l->b, &l->iter,
1186                                                  _k, _k->u64s, _k->u64s);
1187                 }
1188
1189                 break;
1190         }
1191         case BCH_EXTENT_OVERLAP_MIDDLE: {
1192                 BKEY_PADDED(k) split;
1193                 /*
1194                  * The insert key falls 'in the middle' of k
1195                  * The insert key splits k in 3:
1196                  * - start only in k, preserve
1197                  * - middle common section, invalidate in k
1198                  * - end only in k, preserve
1199                  *
1200                  * We update the old key to preserve the start,
1201                  * insert will be the new common section,
1202                  * we manually insert the end that we are preserving.
1203                  *
1204                  * modify k _before_ doing the insert (which will move
1205                  * what k points to)
1206                  */
1207                 bkey_reassemble(&split.k, k.s_c);
1208                 split.k.k.needs_whiteout |= bkey_written(l->b, _k);
1209
1210                 bch2_cut_back(bkey_start_pos(&insert->k), &split.k.k);
1211                 BUG_ON(bkey_deleted(&split.k.k));
1212
1213                 __bch2_cut_front(insert->k.p, k);
1214                 BUG_ON(bkey_deleted(k.k));
1215                 extent_save(l->b, _k, k.k);
1216                 bch2_btree_node_iter_fix(iter, l->b, &l->iter,
1217                                          _k, _k->u64s, _k->u64s);
1218
1219                 extent_bset_insert(c, iter, &split.k);
1220                 break;
1221         }
1222         }
1223 }
1224
1225 struct extent_insert_state {
1226         struct bkey_i                   whiteout;
1227         bool                            update_journal;
1228         bool                            update_btree;
1229         bool                            deleting;
1230 };
1231
1232 static void __bch2_insert_fixup_extent(struct bch_fs *c,
1233                                        struct btree_iter *iter,
1234                                        struct bkey_i *insert,
1235                                        struct extent_insert_state *s)
1236 {
1237         struct btree_iter_level *l = &iter->l[0];
1238         struct bkey_packed *_k;
1239         struct bkey unpacked;
1240
1241         while ((_k = bch2_btree_node_iter_peek_filter(&l->iter, l->b,
1242                                                       KEY_TYPE_discard))) {
1243                 struct bkey_s k = __bkey_disassemble(l->b, _k, &unpacked);
1244                 struct bpos cur_end = bpos_min(insert->k.p, k.k->p);
1245                 enum bch_extent_overlap overlap =
1246                         bch2_extent_overlap(&insert->k, k.k);
1247
1248                 if (bkey_cmp(bkey_start_pos(k.k), insert->k.p) >= 0)
1249                         break;
1250
1251                 if (!bkey_whiteout(k.k))
1252                         s->update_journal = true;
1253
1254                 if (!s->update_journal) {
1255                         bch2_cut_front(cur_end, insert);
1256                         bch2_cut_front(cur_end, &s->whiteout);
1257                         bch2_btree_iter_set_pos_same_leaf(iter, cur_end);
1258                         goto next;
1259                 }
1260
1261                 /*
1262                  * When deleting, if possible just do it by switching the type
1263                  * of the key we're deleting, instead of creating and inserting
1264                  * a new whiteout:
1265                  */
1266                 if (s->deleting &&
1267                     !s->update_btree &&
1268                     !bkey_cmp(insert->k.p, k.k->p) &&
1269                     !bkey_cmp(bkey_start_pos(&insert->k), bkey_start_pos(k.k))) {
1270                         if (!bkey_whiteout(k.k)) {
1271                                 btree_account_key_drop(l->b, _k);
1272                                 _k->type = KEY_TYPE_discard;
1273                                 reserve_whiteout(l->b, _k);
1274                                 bch2_btree_node_iter_fix(iter, l->b, &l->iter,
1275                                                         _k, _k->u64s, _k->u64s);
1276                         }
1277                         break;
1278                 }
1279
1280                 if (k.k->needs_whiteout || bkey_written(l->b, _k)) {
1281                         insert->k.needs_whiteout = true;
1282                         s->update_btree = true;
1283                 }
1284
1285                 if (s->update_btree &&
1286                     overlap == BCH_EXTENT_OVERLAP_ALL &&
1287                     bkey_whiteout(k.k) &&
1288                     k.k->needs_whiteout) {
1289                         unreserve_whiteout(l->b, _k);
1290                         _k->needs_whiteout = false;
1291                 }
1292
1293                 extent_squash(c, iter, insert, _k, k, overlap);
1294
1295                 if (!s->update_btree)
1296                         bch2_cut_front(cur_end, insert);
1297 next:
1298                 if (overlap == BCH_EXTENT_OVERLAP_FRONT ||
1299                     overlap == BCH_EXTENT_OVERLAP_MIDDLE)
1300                         break;
1301         }
1302 }
1303
1304 /**
1305  * bch_extent_insert_fixup - insert a new extent and deal with overlaps
1306  *
1307  * this may result in not actually doing the insert, or inserting some subset
1308  * of the insert key. For cmpxchg operations this is where that logic lives.
1309  *
1310  * All subsets of @insert that need to be inserted are inserted using
1311  * bch2_btree_insert_and_journal(). If @b or @res fills up, this function
1312  * returns false, setting @iter->pos for the prefix of @insert that actually got
1313  * inserted.
1314  *
1315  * BSET INVARIANTS: this function is responsible for maintaining all the
1316  * invariants for bsets of extents in memory. things get really hairy with 0
1317  * size extents
1318  *
1319  * within one bset:
1320  *
1321  * bkey_start_pos(bkey_next(k)) >= k
1322  * or bkey_start_offset(bkey_next(k)) >= k->offset
1323  *
1324  * i.e. strict ordering, no overlapping extents.
1325  *
1326  * multiple bsets (i.e. full btree node):
1327  *
1328  * ∀ k, j
1329  *   k.size != 0 ∧ j.size != 0 →
1330  *     ¬ (k > bkey_start_pos(j) ∧ k < j)
1331  *
1332  * i.e. no two overlapping keys _of nonzero size_
1333  *
1334  * We can't realistically maintain this invariant for zero size keys because of
1335  * the key merging done in bch2_btree_insert_key() - for two mergeable keys k, j
1336  * there may be another 0 size key between them in another bset, and it will
1337  * thus overlap with the merged key.
1338  *
1339  * In addition, the end of iter->pos indicates how much has been processed.
1340  * If the end of iter->pos is not the same as the end of insert, then
1341  * key insertion needs to continue/be retried.
1342  */
1343 void bch2_insert_fixup_extent(struct btree_trans *trans,
1344                               struct btree_insert_entry *insert)
1345 {
1346         struct bch_fs *c = trans->c;
1347         struct btree_iter *iter = insert->iter;
1348         struct extent_insert_state s = {
1349                 .whiteout       = *insert->k,
1350                 .update_journal = !bkey_whiteout(&insert->k->k),
1351                 .update_btree   = !bkey_whiteout(&insert->k->k),
1352                 .deleting       = bkey_whiteout(&insert->k->k),
1353         };
1354         BKEY_PADDED(k) tmp;
1355
1356         EBUG_ON(iter->level);
1357         EBUG_ON(!insert->k->k.size);
1358         EBUG_ON(bkey_cmp(iter->pos, bkey_start_pos(&insert->k->k)));
1359
1360         __bch2_insert_fixup_extent(c, iter, insert->k, &s);
1361
1362         bch2_btree_iter_set_pos_same_leaf(iter, insert->k->k.p);
1363
1364         if (s.update_btree) {
1365                 bkey_copy(&tmp.k, insert->k);
1366
1367                 if (s.deleting)
1368                         tmp.k.k.type = KEY_TYPE_discard;
1369
1370                 EBUG_ON(bkey_deleted(&tmp.k.k) || !tmp.k.k.size);
1371
1372                 extent_bset_insert(c, iter, &tmp.k);
1373         }
1374
1375         if (s.update_journal) {
1376                 bkey_copy(&tmp.k, !s.deleting ? insert->k : &s.whiteout);
1377
1378                 if (s.deleting)
1379                         tmp.k.k.type = KEY_TYPE_discard;
1380
1381                 EBUG_ON(bkey_deleted(&tmp.k.k) || !tmp.k.k.size);
1382
1383                 bch2_btree_journal_key(trans, iter, &tmp.k);
1384         }
1385
1386         bch2_cut_front(insert->k->k.p, insert->k);
1387 }
1388
1389 const char *bch2_extent_invalid(const struct bch_fs *c, struct bkey_s_c k)
1390 {
1391         return bch2_bkey_ptrs_invalid(c, k);
1392 }
1393
1394 void bch2_extent_debugcheck(struct bch_fs *c, struct bkey_s_c k)
1395 {
1396         struct bkey_s_c_extent e = bkey_s_c_to_extent(k);
1397         const union bch_extent_entry *entry;
1398         struct extent_ptr_decoded p;
1399         char buf[160];
1400
1401         /*
1402          * XXX: we should be doing most/all of these checks at startup time,
1403          * where we check bch2_bkey_invalid() in btree_node_read_done()
1404          *
1405          * But note that we can't check for stale pointers or incorrect gc marks
1406          * until after journal replay is done (it might be an extent that's
1407          * going to get overwritten during replay)
1408          */
1409
1410         if (percpu_down_read_trylock(&c->mark_lock)) {
1411                 bch2_fs_bug_on(!test_bit(BCH_FS_REBUILD_REPLICAS, &c->flags) &&
1412                                !bch2_bkey_replicas_marked_locked(c, e.s_c, false), c,
1413                                "extent key bad (replicas not marked in superblock):\n%s",
1414                                (bch2_bkey_val_to_text(&PBUF(buf), c, e.s_c), buf));
1415                 percpu_up_read(&c->mark_lock);
1416         }
1417         /*
1418          * If journal replay hasn't finished, we might be seeing keys
1419          * that will be overwritten by the time journal replay is done:
1420          */
1421         if (!test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags))
1422                 return;
1423
1424         extent_for_each_ptr_decode(e, p, entry) {
1425                 struct bch_dev *ca      = bch_dev_bkey_exists(c, p.ptr.dev);
1426                 struct bucket_mark mark = ptr_bucket_mark(ca, &p.ptr);
1427                 unsigned stale          = gen_after(mark.gen, p.ptr.gen);
1428                 unsigned disk_sectors   = ptr_disk_sectors(p);
1429                 unsigned mark_sectors   = p.ptr.cached
1430                         ? mark.cached_sectors
1431                         : mark.dirty_sectors;
1432
1433                 bch2_fs_bug_on(stale && !p.ptr.cached, c,
1434                                "stale dirty pointer (ptr gen %u bucket %u",
1435                                p.ptr.gen, mark.gen);
1436
1437                 bch2_fs_bug_on(stale > 96, c, "key too stale: %i", stale);
1438
1439                 bch2_fs_bug_on(!stale &&
1440                                (mark.data_type != BCH_DATA_USER ||
1441                                 mark_sectors < disk_sectors), c,
1442                                "extent pointer not marked: %s:\n"
1443                                "type %u sectors %u < %u",
1444                                (bch2_bkey_val_to_text(&PBUF(buf), c, e.s_c), buf),
1445                                mark.data_type,
1446                                mark_sectors, disk_sectors);
1447         }
1448 }
1449
1450 void bch2_extent_to_text(struct printbuf *out, struct bch_fs *c,
1451                          struct bkey_s_c k)
1452 {
1453         bch2_bkey_ptrs_to_text(out, c, k);
1454 }
1455
1456 static unsigned bch2_crc_field_size_max[] = {
1457         [BCH_EXTENT_ENTRY_crc32] = CRC32_SIZE_MAX,
1458         [BCH_EXTENT_ENTRY_crc64] = CRC64_SIZE_MAX,
1459         [BCH_EXTENT_ENTRY_crc128] = CRC128_SIZE_MAX,
1460 };
1461
1462 static void bch2_extent_crc_pack(union bch_extent_crc *dst,
1463                                  struct bch_extent_crc_unpacked src)
1464 {
1465 #define set_common_fields(_dst, _src)                                   \
1466                 _dst.csum_type          = _src.csum_type,               \
1467                 _dst.compression_type   = _src.compression_type,        \
1468                 _dst._compressed_size   = _src.compressed_size - 1,     \
1469                 _dst._uncompressed_size = _src.uncompressed_size - 1,   \
1470                 _dst.offset             = _src.offset
1471
1472         switch (extent_entry_type(to_entry(dst))) {
1473         case BCH_EXTENT_ENTRY_crc32:
1474                 set_common_fields(dst->crc32, src);
1475                 dst->crc32.csum  = *((__le32 *) &src.csum.lo);
1476                 break;
1477         case BCH_EXTENT_ENTRY_crc64:
1478                 set_common_fields(dst->crc64, src);
1479                 dst->crc64.nonce        = src.nonce;
1480                 dst->crc64.csum_lo      = src.csum.lo;
1481                 dst->crc64.csum_hi      = *((__le16 *) &src.csum.hi);
1482                 break;
1483         case BCH_EXTENT_ENTRY_crc128:
1484                 set_common_fields(dst->crc128, src);
1485                 dst->crc128.nonce       = src.nonce;
1486                 dst->crc128.csum        = src.csum;
1487                 break;
1488         default:
1489                 BUG();
1490         }
1491 #undef set_common_fields
1492 }
1493
1494 static void bch2_extent_crc_append(struct bkey_i *k,
1495                                    struct bch_extent_crc_unpacked new)
1496 {
1497         struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
1498         union bch_extent_crc *crc = (void *) ptrs.end;
1499
1500         if (bch_crc_bytes[new.csum_type]        <= 4 &&
1501             new.uncompressed_size - 1           <= CRC32_SIZE_MAX &&
1502             new.nonce                           <= CRC32_NONCE_MAX)
1503                 crc->type = 1 << BCH_EXTENT_ENTRY_crc32;
1504         else if (bch_crc_bytes[new.csum_type]   <= 10 &&
1505                    new.uncompressed_size - 1    <= CRC64_SIZE_MAX &&
1506                    new.nonce                    <= CRC64_NONCE_MAX)
1507                 crc->type = 1 << BCH_EXTENT_ENTRY_crc64;
1508         else if (bch_crc_bytes[new.csum_type]   <= 16 &&
1509                    new.uncompressed_size - 1    <= CRC128_SIZE_MAX &&
1510                    new.nonce                    <= CRC128_NONCE_MAX)
1511                 crc->type = 1 << BCH_EXTENT_ENTRY_crc128;
1512         else
1513                 BUG();
1514
1515         bch2_extent_crc_pack(crc, new);
1516
1517         k->k.u64s += extent_entry_u64s(ptrs.end);
1518
1519         EBUG_ON(bkey_val_u64s(&k->k) > BKEY_EXTENT_VAL_U64s_MAX);
1520 }
1521
1522 static inline void __extent_entry_insert(struct bkey_i *k,
1523                                          union bch_extent_entry *dst,
1524                                          union bch_extent_entry *new)
1525 {
1526         union bch_extent_entry *end = bkey_val_end(bkey_i_to_s(k));
1527
1528         memmove_u64s_up((u64 *) dst + extent_entry_u64s(new),
1529                         dst, (u64 *) end - (u64 *) dst);
1530         k->k.u64s += extent_entry_u64s(new);
1531         memcpy(dst, new, extent_entry_bytes(new));
1532 }
1533
1534 void bch2_extent_ptr_decoded_append(struct bkey_i *k,
1535                                     struct extent_ptr_decoded *p)
1536 {
1537         struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
1538         struct bch_extent_crc_unpacked crc =
1539                 bch2_extent_crc_unpack(&k->k, NULL);
1540         union bch_extent_entry *pos;
1541         unsigned i;
1542
1543         if (!bch2_crc_unpacked_cmp(crc, p->crc)) {
1544                 pos = ptrs.start;
1545                 goto found;
1546         }
1547
1548         bkey_for_each_crc(&k->k, ptrs, crc, pos)
1549                 if (!bch2_crc_unpacked_cmp(crc, p->crc)) {
1550                         pos = extent_entry_next(pos);
1551                         goto found;
1552                 }
1553
1554         bch2_extent_crc_append(k, p->crc);
1555         pos = bkey_val_end(bkey_i_to_s(k));
1556 found:
1557         p->ptr.type = 1 << BCH_EXTENT_ENTRY_ptr;
1558         __extent_entry_insert(k, pos, to_entry(&p->ptr));
1559
1560         for (i = 0; i < p->ec_nr; i++) {
1561                 p->ec[i].type = 1 << BCH_EXTENT_ENTRY_stripe_ptr;
1562                 __extent_entry_insert(k, pos, to_entry(&p->ec[i]));
1563         }
1564 }
1565
1566 /*
1567  * bch_extent_normalize - clean up an extent, dropping stale pointers etc.
1568  *
1569  * Returns true if @k should be dropped entirely
1570  *
1571  * For existing keys, only called when btree nodes are being rewritten, not when
1572  * they're merely being compacted/resorted in memory.
1573  */
1574 bool bch2_extent_normalize(struct bch_fs *c, struct bkey_s k)
1575 {
1576         struct bch_extent_ptr *ptr;
1577
1578         bch2_bkey_drop_ptrs(k, ptr,
1579                 ptr->cached &&
1580                 ptr_stale(bch_dev_bkey_exists(c, ptr->dev), ptr));
1581
1582         /* will only happen if all pointers were cached: */
1583         if (!bkey_val_u64s(k.k))
1584                 k.k->type = KEY_TYPE_discard;
1585
1586         return bkey_whiteout(k.k);
1587 }
1588
1589 void bch2_bkey_mark_replicas_cached(struct bch_fs *c, struct bkey_s k,
1590                                     unsigned target,
1591                                     unsigned nr_desired_replicas)
1592 {
1593         struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
1594         union bch_extent_entry *entry;
1595         struct extent_ptr_decoded p;
1596         int extra = bch2_bkey_durability(c, k.s_c) - nr_desired_replicas;
1597
1598         if (target && extra > 0)
1599                 bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
1600                         int n = bch2_extent_ptr_durability(c, p);
1601
1602                         if (n && n <= extra &&
1603                             !bch2_dev_in_target(c, p.ptr.dev, target)) {
1604                                 entry->ptr.cached = true;
1605                                 extra -= n;
1606                         }
1607                 }
1608
1609         if (extra > 0)
1610                 bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
1611                         int n = bch2_extent_ptr_durability(c, p);
1612
1613                         if (n && n <= extra) {
1614                                 entry->ptr.cached = true;
1615                                 extra -= n;
1616                         }
1617                 }
1618 }
1619
1620 enum merge_result bch2_extent_merge(struct bch_fs *c,
1621                                     struct bkey_s _l, struct bkey_s _r)
1622 {
1623         struct bkey_s_extent l = bkey_s_to_extent(_l);
1624         struct bkey_s_extent r = bkey_s_to_extent(_r);
1625         union bch_extent_entry *en_l = l.v->start;
1626         union bch_extent_entry *en_r = r.v->start;
1627         struct bch_extent_crc_unpacked crc_l, crc_r;
1628
1629         if (bkey_val_u64s(l.k) != bkey_val_u64s(r.k))
1630                 return BCH_MERGE_NOMERGE;
1631
1632         crc_l = bch2_extent_crc_unpack(l.k, NULL);
1633
1634         extent_for_each_entry(l, en_l) {
1635                 en_r = vstruct_idx(r.v, (u64 *) en_l - l.v->_data);
1636
1637                 if (extent_entry_type(en_l) != extent_entry_type(en_r))
1638                         return BCH_MERGE_NOMERGE;
1639
1640                 switch (extent_entry_type(en_l)) {
1641                 case BCH_EXTENT_ENTRY_ptr: {
1642                         const struct bch_extent_ptr *lp = &en_l->ptr;
1643                         const struct bch_extent_ptr *rp = &en_r->ptr;
1644                         struct bch_dev *ca;
1645
1646                         if (lp->offset + crc_l.compressed_size != rp->offset ||
1647                             lp->dev                     != rp->dev ||
1648                             lp->gen                     != rp->gen)
1649                                 return BCH_MERGE_NOMERGE;
1650
1651                         /* We don't allow extents to straddle buckets: */
1652                         ca = bch_dev_bkey_exists(c, lp->dev);
1653
1654                         if (PTR_BUCKET_NR(ca, lp) != PTR_BUCKET_NR(ca, rp))
1655                                 return BCH_MERGE_NOMERGE;
1656
1657                         break;
1658                 }
1659                 case BCH_EXTENT_ENTRY_stripe_ptr:
1660                         if (en_l->stripe_ptr.block      != en_r->stripe_ptr.block ||
1661                             en_l->stripe_ptr.idx        != en_r->stripe_ptr.idx)
1662                                 return BCH_MERGE_NOMERGE;
1663                         break;
1664                 case BCH_EXTENT_ENTRY_crc32:
1665                 case BCH_EXTENT_ENTRY_crc64:
1666                 case BCH_EXTENT_ENTRY_crc128:
1667                         crc_l = bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
1668                         crc_r = bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
1669
1670                         if (crc_l.csum_type             != crc_r.csum_type ||
1671                             crc_l.compression_type      != crc_r.compression_type ||
1672                             crc_l.nonce                 != crc_r.nonce)
1673                                 return BCH_MERGE_NOMERGE;
1674
1675                         if (crc_l.offset + crc_l.live_size != crc_l.compressed_size ||
1676                             crc_r.offset)
1677                                 return BCH_MERGE_NOMERGE;
1678
1679                         if (!bch2_checksum_mergeable(crc_l.csum_type))
1680                                 return BCH_MERGE_NOMERGE;
1681
1682                         if (crc_l.compression_type)
1683                                 return BCH_MERGE_NOMERGE;
1684
1685                         if (crc_l.csum_type &&
1686                             crc_l.uncompressed_size +
1687                             crc_r.uncompressed_size > c->sb.encoded_extent_max)
1688                                 return BCH_MERGE_NOMERGE;
1689
1690                         if (crc_l.uncompressed_size + crc_r.uncompressed_size - 1 >
1691                             bch2_crc_field_size_max[extent_entry_type(en_l)])
1692                                 return BCH_MERGE_NOMERGE;
1693
1694                         break;
1695                 default:
1696                         return BCH_MERGE_NOMERGE;
1697                 }
1698         }
1699
1700         extent_for_each_entry(l, en_l) {
1701                 struct bch_extent_crc_unpacked crc_l, crc_r;
1702
1703                 en_r = vstruct_idx(r.v, (u64 *) en_l - l.v->_data);
1704
1705                 if (!extent_entry_is_crc(en_l))
1706                         continue;
1707
1708                 crc_l = bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
1709                 crc_r = bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
1710
1711                 crc_l.csum = bch2_checksum_merge(crc_l.csum_type,
1712                                                  crc_l.csum,
1713                                                  crc_r.csum,
1714                                                  crc_r.uncompressed_size << 9);
1715
1716                 crc_l.uncompressed_size += crc_r.uncompressed_size;
1717                 crc_l.compressed_size   += crc_r.compressed_size;
1718
1719                 bch2_extent_crc_pack(entry_to_crc(en_l), crc_l);
1720         }
1721
1722         bch2_key_resize(l.k, l.k->size + r.k->size);
1723
1724         return BCH_MERGE_MERGE;
1725 }
1726
1727 /*
1728  * When merging an extent that we're inserting into a btree node, the new merged
1729  * extent could overlap with an existing 0 size extent - if we don't fix that,
1730  * it'll break the btree node iterator so this code finds those 0 size extents
1731  * and shifts them out of the way.
1732  *
1733  * Also unpacks and repacks.
1734  */
1735 static bool bch2_extent_merge_inline(struct bch_fs *c,
1736                                      struct btree_iter *iter,
1737                                      struct bkey_packed *l,
1738                                      struct bkey_packed *r,
1739                                      bool back_merge)
1740 {
1741         struct btree *b = iter->l[0].b;
1742         struct btree_node_iter *node_iter = &iter->l[0].iter;
1743         BKEY_PADDED(k) li, ri;
1744         struct bkey_packed *m   = back_merge ? l : r;
1745         struct bkey_i *mi       = back_merge ? &li.k : &ri.k;
1746         struct bset_tree *t     = bch2_bkey_to_bset(b, m);
1747         enum merge_result ret;
1748
1749         EBUG_ON(bkey_written(b, m));
1750
1751         if (bkey_val_u64s(l) > BKEY_EXTENT_VAL_U64s_MAX ||
1752             bkey_val_u64s(r) > BKEY_EXTENT_VAL_U64s_MAX)
1753                 return BCH_MERGE_NOMERGE;
1754
1755         /*
1756          * We need to save copies of both l and r, because we might get a
1757          * partial merge (which modifies both) and then fails to repack
1758          */
1759         bch2_bkey_unpack(b, &li.k, l);
1760         bch2_bkey_unpack(b, &ri.k, r);
1761
1762         ret = bch2_bkey_merge(c,
1763                               bkey_i_to_s(&li.k),
1764                               bkey_i_to_s(&ri.k));
1765         if (ret == BCH_MERGE_NOMERGE)
1766                 return false;
1767
1768         if (debug_check_bkeys(c))
1769                 bch2_bkey_debugcheck(c, b, bkey_i_to_s_c(&li.k));
1770         if (debug_check_bkeys(c) &&
1771             ret == BCH_MERGE_PARTIAL)
1772                 bch2_bkey_debugcheck(c, b, bkey_i_to_s_c(&ri.k));
1773
1774         /*
1775          * check if we overlap with deleted extents - would break the sort
1776          * order:
1777          */
1778         if (back_merge) {
1779                 struct bkey_packed *n = bkey_next(m);
1780
1781                 if (n != btree_bkey_last(b, t) &&
1782                     bkey_cmp_left_packed(b, n, &li.k.k.p) <= 0 &&
1783                     bkey_deleted(n))
1784                         return false;
1785         } else if (ret == BCH_MERGE_MERGE) {
1786                 struct bkey_packed *prev = bch2_bkey_prev_all(b, t, m);
1787
1788                 if (prev &&
1789                     bkey_cmp_left_packed_byval(b, prev,
1790                                 bkey_start_pos(&li.k.k)) > 0)
1791                         return false;
1792         }
1793
1794         if (ret == BCH_MERGE_PARTIAL) {
1795                 if (!extent_i_save(b, m, mi))
1796                         return false;
1797
1798                 if (!back_merge)
1799                         bkey_copy(packed_to_bkey(l), &li.k);
1800                 else
1801                         bkey_copy(packed_to_bkey(r), &ri.k);
1802         } else {
1803                 if (!extent_i_save(b, m, &li.k))
1804                         return false;
1805         }
1806
1807         bch2_bset_fix_invalidated_key(b, m);
1808         bch2_btree_node_iter_fix(iter, b, node_iter,
1809                                  m, m->u64s, m->u64s);
1810
1811         return ret == BCH_MERGE_MERGE;
1812 }
1813
1814 bool bch2_check_range_allocated(struct bch_fs *c, struct bpos pos, u64 size,
1815                                unsigned nr_replicas)
1816 {
1817         struct btree_trans trans;
1818         struct btree_iter *iter;
1819         struct bpos end = pos;
1820         struct bkey_s_c k;
1821         bool ret = true;
1822         int err;
1823
1824         end.offset += size;
1825
1826         bch2_trans_init(&trans, c, 0, 0);
1827
1828         for_each_btree_key(&trans, iter, BTREE_ID_EXTENTS, pos,
1829                            BTREE_ITER_SLOTS, k, err) {
1830                 if (bkey_cmp(bkey_start_pos(k.k), end) >= 0)
1831                         break;
1832
1833                 if (nr_replicas > bch2_bkey_nr_ptrs_allocated(k)) {
1834                         ret = false;
1835                         break;
1836                 }
1837         }
1838         bch2_trans_exit(&trans);
1839
1840         return ret;
1841 }
1842
1843 unsigned bch2_bkey_nr_ptrs_allocated(struct bkey_s_c k)
1844 {
1845         unsigned ret = 0;
1846
1847         switch (k.k->type) {
1848         case KEY_TYPE_extent: {
1849                 struct bkey_s_c_extent e = bkey_s_c_to_extent(k);
1850                 const union bch_extent_entry *entry;
1851                 struct extent_ptr_decoded p;
1852
1853                 extent_for_each_ptr_decode(e, p, entry)
1854                         ret += !p.ptr.cached &&
1855                                 p.crc.compression_type == BCH_COMPRESSION_NONE;
1856                 break;
1857         }
1858         case KEY_TYPE_reservation:
1859                 ret = bkey_s_c_to_reservation(k).v->nr_replicas;
1860                 break;
1861         }
1862
1863         return ret;
1864 }
1865
1866 /* KEY_TYPE_reservation: */
1867
1868 const char *bch2_reservation_invalid(const struct bch_fs *c, struct bkey_s_c k)
1869 {
1870         struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
1871
1872         if (bkey_val_bytes(k.k) != sizeof(struct bch_reservation))
1873                 return "incorrect value size";
1874
1875         if (!r.v->nr_replicas || r.v->nr_replicas > BCH_REPLICAS_MAX)
1876                 return "invalid nr_replicas";
1877
1878         return NULL;
1879 }
1880
1881 void bch2_reservation_to_text(struct printbuf *out, struct bch_fs *c,
1882                               struct bkey_s_c k)
1883 {
1884         struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
1885
1886         pr_buf(out, "generation %u replicas %u",
1887                le32_to_cpu(r.v->generation),
1888                r.v->nr_replicas);
1889 }
1890
1891 enum merge_result bch2_reservation_merge(struct bch_fs *c,
1892                                          struct bkey_s _l, struct bkey_s _r)
1893 {
1894         struct bkey_s_reservation l = bkey_s_to_reservation(_l);
1895         struct bkey_s_reservation r = bkey_s_to_reservation(_r);
1896
1897         if (l.v->generation != r.v->generation ||
1898             l.v->nr_replicas != r.v->nr_replicas)
1899                 return BCH_MERGE_NOMERGE;
1900
1901         if ((u64) l.k->size + r.k->size > KEY_SIZE_MAX) {
1902                 bch2_key_resize(l.k, KEY_SIZE_MAX);
1903                 __bch2_cut_front(l.k->p, r.s);
1904                 return BCH_MERGE_PARTIAL;
1905         }
1906
1907         bch2_key_resize(l.k, l.k->size + r.k->size);
1908
1909         return BCH_MERGE_MERGE;
1910 }