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_io.h"
  13 #include "btree_iter.h"
  14 #include "buckets.h"
  15 #include "checksum.h"
  16 #include "debug.h"
  17 #include "disk_groups.h"
  18 #include "error.h"
  19 #include "extents.h"
  20 #include "inode.h"
  21 #include "journal.h"
  22 #include "replicas.h"
  23 #include "super.h"
  24 #include "super-io.h"
  25 #include "trace.h"
  26 #include "util.h"
  27
  28 static unsigned bch2_crc_field_size_max[] = {
  29         [BCH_EXTENT_ENTRY_crc32] = CRC32_SIZE_MAX,
  30         [BCH_EXTENT_ENTRY_crc64] = CRC64_SIZE_MAX,
  31         [BCH_EXTENT_ENTRY_crc128] = CRC128_SIZE_MAX,
  32 };
  33
  34 static void bch2_extent_crc_pack(union bch_extent_crc *,
  35                                  struct bch_extent_crc_unpacked,
  36                                  enum bch_extent_entry_type);
  37
  38 static struct bch_dev_io_failures *dev_io_failures(struct bch_io_failures *f,
  39                                                    unsigned dev)
  40 {
  41         struct bch_dev_io_failures *i;
  42
  43         for (i = f->devs; i < f->devs + f->nr; i++)
  44                 if (i->dev == dev)
  45                         return i;
  46
  47         return NULL;
  48 }
  49
  50 void bch2_mark_io_failure(struct bch_io_failures *failed,
  51                           struct extent_ptr_decoded *p)
  52 {
  53         struct bch_dev_io_failures *f = dev_io_failures(failed, p->ptr.dev);
  54
  55         if (!f) {
  56                 BUG_ON(failed->nr >= ARRAY_SIZE(failed->devs));
  57
  58                 f = &failed->devs[failed->nr++];
  59                 f->dev          = p->ptr.dev;
  60                 f->idx          = p->idx;
  61                 f->nr_failed    = 1;
  62                 f->nr_retries   = 0;
  63         } else if (p->idx != f->idx) {
  64                 f->idx          = p->idx;
  65                 f->nr_failed    = 1;
  66                 f->nr_retries   = 0;
  67         } else {
  68                 f->nr_failed++;
  69         }
  70 }
  71
  72 /*
  73  * returns true if p1 is better than p2:
  74  */
  75 static inline bool ptr_better(struct bch_fs *c,
  76                               const struct extent_ptr_decoded p1,
  77                               const struct extent_ptr_decoded p2)
  78 {
  79         if (likely(!p1.idx && !p2.idx)) {
  80                 struct bch_dev *dev1 = bch_dev_bkey_exists(c, p1.ptr.dev);
  81                 struct bch_dev *dev2 = bch_dev_bkey_exists(c, p2.ptr.dev);
  82
  83                 u64 l1 = atomic64_read(&dev1->cur_latency[READ]);
  84                 u64 l2 = atomic64_read(&dev2->cur_latency[READ]);
  85
  86                 /* Pick at random, biased in favor of the faster device: */
  87
  88                 return bch2_rand_range(l1 + l2) > l1;
  89         }
  90
  91         if (bch2_force_reconstruct_read)
  92                 return p1.idx > p2.idx;
  93
  94         return p1.idx < p2.idx;
  95 }
  96
  97 /*
  98  * This picks a non-stale pointer, preferably from a device other than @avoid.
  99  * Avoid can be NULL, meaning pick any. If there are no non-stale pointers to
 100  * other devices, it will still pick a pointer from avoid.
 101  */
 102 int bch2_bkey_pick_read_device(struct bch_fs *c, struct bkey_s_c k,
 103                                struct bch_io_failures *failed,
 104                                struct extent_ptr_decoded *pick)
 105 {
 106         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 107         const union bch_extent_entry *entry;
 108         struct extent_ptr_decoded p;
 109         struct bch_dev_io_failures *f;
 110         struct bch_dev *ca;
 111         int ret = 0;
 112
 113         if (k.k->type == KEY_TYPE_error)
 114                 return -EIO;
 115
 116         bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
 117                 /*
 118                  * Unwritten extent: no need to actually read, treat it as a
 119                  * hole and return 0s:
 120                  */
 121                 if (p.ptr.unwritten)
 122                         return 0;
 123
 124                 ca = bch_dev_bkey_exists(c, p.ptr.dev);
 125
 126                 /*
 127                  * If there are any dirty pointers it's an error if we can't
 128                  * read:
 129                  */
 130                 if (!ret && !p.ptr.cached)
 131                         ret = -EIO;
 132
 133                 if (p.ptr.cached && ptr_stale(ca, &p.ptr))
 134                         continue;
 135
 136                 f = failed ? dev_io_failures(failed, p.ptr.dev) : NULL;
 137                 if (f)
 138                         p.idx = f->nr_failed < f->nr_retries
 139                                 ? f->idx
 140                                 : f->idx + 1;
 141
 142                 if (!p.idx &&
 143                     !bch2_dev_is_readable(ca))
 144                         p.idx++;
 145
 146                 if (bch2_force_reconstruct_read &&
 147                     !p.idx && p.has_ec)
 148                         p.idx++;
 149
 150                 if (p.idx >= (unsigned) p.has_ec + 1)
 151                         continue;
 152
 153                 if (ret > 0 && !ptr_better(c, p, *pick))
 154                         continue;
 155
 156                 *pick = p;
 157                 ret = 1;
 158         }
 159
 160         return ret;
 161 }
 162
 163 /* KEY_TYPE_btree_ptr: */
 164
 165 int bch2_btree_ptr_invalid(const struct bch_fs *c, struct bkey_s_c k,
 166                            unsigned flags, struct printbuf *err)
 167 {
 168         if (bkey_val_u64s(k.k) > BCH_REPLICAS_MAX) {
 169                 prt_printf(err, "value too big (%zu > %u)",
 170                        bkey_val_u64s(k.k), BCH_REPLICAS_MAX);
 171                 return -BCH_ERR_invalid_bkey;
 172         }
 173
 174         return bch2_bkey_ptrs_invalid(c, k, flags, err);
 175 }
 176
 177 void bch2_btree_ptr_to_text(struct printbuf *out, struct bch_fs *c,
 178                             struct bkey_s_c k)
 179 {
 180         bch2_bkey_ptrs_to_text(out, c, k);
 181 }
 182
 183 int bch2_btree_ptr_v2_invalid(const struct bch_fs *c, struct bkey_s_c k,
 184                               unsigned flags, struct printbuf *err)
 185 {
 186         if (bkey_val_u64s(k.k) > BKEY_BTREE_PTR_VAL_U64s_MAX) {
 187                 prt_printf(err, "value too big (%zu > %zu)",
 188                        bkey_val_u64s(k.k), BKEY_BTREE_PTR_VAL_U64s_MAX);
 189                 return -BCH_ERR_invalid_bkey;
 190         }
 191
 192         return bch2_bkey_ptrs_invalid(c, k, flags, err);
 193 }
 194
 195 void bch2_btree_ptr_v2_to_text(struct printbuf *out, struct bch_fs *c,
 196                                struct bkey_s_c k)
 197 {
 198         struct bkey_s_c_btree_ptr_v2 bp = bkey_s_c_to_btree_ptr_v2(k);
 199
 200         prt_printf(out, "seq %llx written %u min_key %s",
 201                le64_to_cpu(bp.v->seq),
 202                le16_to_cpu(bp.v->sectors_written),
 203                BTREE_PTR_RANGE_UPDATED(bp.v) ? "R " : "");
 204
 205         bch2_bpos_to_text(out, bp.v->min_key);
 206         prt_printf(out, " ");
 207         bch2_bkey_ptrs_to_text(out, c, k);
 208 }
 209
 210 void bch2_btree_ptr_v2_compat(enum btree_id btree_id, unsigned version,
 211                               unsigned big_endian, int write,
 212                               struct bkey_s k)
 213 {
 214         struct bkey_s_btree_ptr_v2 bp = bkey_s_to_btree_ptr_v2(k);
 215
 216         compat_bpos(0, btree_id, version, big_endian, write, &bp.v->min_key);
 217
 218         if (version < bcachefs_metadata_version_inode_btree_change &&
 219             btree_node_type_is_extents(btree_id) &&
 220             !bkey_eq(bp.v->min_key, POS_MIN))
 221                 bp.v->min_key = write
 222                         ? bpos_nosnap_predecessor(bp.v->min_key)
 223                         : bpos_nosnap_successor(bp.v->min_key);
 224 }
 225
 226 /* KEY_TYPE_extent: */
 227
 228 bool bch2_extent_merge(struct bch_fs *c, struct bkey_s l, struct bkey_s_c r)
 229 {
 230         struct bkey_ptrs   l_ptrs = bch2_bkey_ptrs(l);
 231         struct bkey_ptrs_c r_ptrs = bch2_bkey_ptrs_c(r);
 232         union bch_extent_entry *en_l;
 233         const union bch_extent_entry *en_r;
 234         struct extent_ptr_decoded lp, rp;
 235         bool use_right_ptr;
 236         struct bch_dev *ca;
 237
 238         en_l = l_ptrs.start;
 239         en_r = r_ptrs.start;
 240         while (en_l < l_ptrs.end && en_r < r_ptrs.end) {
 241                 if (extent_entry_type(en_l) != extent_entry_type(en_r))
 242                         return false;
 243
 244                 en_l = extent_entry_next(en_l);
 245                 en_r = extent_entry_next(en_r);
 246         }
 247
 248         if (en_l < l_ptrs.end || en_r < r_ptrs.end)
 249                 return false;
 250
 251         en_l = l_ptrs.start;
 252         en_r = r_ptrs.start;
 253         lp.crc = bch2_extent_crc_unpack(l.k, NULL);
 254         rp.crc = bch2_extent_crc_unpack(r.k, NULL);
 255
 256         while (__bkey_ptr_next_decode(l.k, l_ptrs.end, lp, en_l) &&
 257                __bkey_ptr_next_decode(r.k, r_ptrs.end, rp, en_r)) {
 258                 if (lp.ptr.offset + lp.crc.offset + lp.crc.live_size !=
 259                     rp.ptr.offset + rp.crc.offset ||
 260                     lp.ptr.dev                  != rp.ptr.dev ||
 261                     lp.ptr.gen                  != rp.ptr.gen ||
 262                     lp.ptr.unwritten            != rp.ptr.unwritten ||
 263                     lp.has_ec                   != rp.has_ec)
 264                         return false;
 265
 266                 /* Extents may not straddle buckets: */
 267                 ca = bch_dev_bkey_exists(c, lp.ptr.dev);
 268                 if (PTR_BUCKET_NR(ca, &lp.ptr) != PTR_BUCKET_NR(ca, &rp.ptr))
 269                         return false;
 270
 271                 if (lp.has_ec                   != rp.has_ec ||
 272                     (lp.has_ec &&
 273                      (lp.ec.block               != rp.ec.block ||
 274                       lp.ec.redundancy          != rp.ec.redundancy ||
 275                       lp.ec.idx                 != rp.ec.idx)))
 276                         return false;
 277
 278                 if (lp.crc.compression_type     != rp.crc.compression_type ||
 279                     lp.crc.nonce                != rp.crc.nonce)
 280                         return false;
 281
 282                 if (lp.crc.offset + lp.crc.live_size + rp.crc.live_size <=
 283                     lp.crc.uncompressed_size) {
 284                         /* can use left extent's crc entry */
 285                 } else if (lp.crc.live_size <= rp.crc.offset) {
 286                         /* can use right extent's crc entry */
 287                 } else {
 288                         /* check if checksums can be merged: */
 289                         if (lp.crc.csum_type            != rp.crc.csum_type ||
 290                             lp.crc.nonce                != rp.crc.nonce ||
 291                             crc_is_compressed(lp.crc) ||
 292                             !bch2_checksum_mergeable(lp.crc.csum_type))
 293                                 return false;
 294
 295                         if (lp.crc.offset + lp.crc.live_size != lp.crc.compressed_size ||
 296                             rp.crc.offset)
 297                                 return false;
 298
 299                         if (lp.crc.csum_type &&
 300                             lp.crc.uncompressed_size +
 301                             rp.crc.uncompressed_size > (c->opts.encoded_extent_max >> 9))
 302                                 return false;
 303                 }
 304
 305                 en_l = extent_entry_next(en_l);
 306                 en_r = extent_entry_next(en_r);
 307         }
 308
 309         en_l = l_ptrs.start;
 310         en_r = r_ptrs.start;
 311         while (en_l < l_ptrs.end && en_r < r_ptrs.end) {
 312                 if (extent_entry_is_crc(en_l)) {
 313                         struct bch_extent_crc_unpacked crc_l = bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
 314                         struct bch_extent_crc_unpacked crc_r = bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
 315
 316                         if (crc_l.uncompressed_size + crc_r.uncompressed_size >
 317                             bch2_crc_field_size_max[extent_entry_type(en_l)])
 318                                 return false;
 319                 }
 320
 321                 en_l = extent_entry_next(en_l);
 322                 en_r = extent_entry_next(en_r);
 323         }
 324
 325         use_right_ptr = false;
 326         en_l = l_ptrs.start;
 327         en_r = r_ptrs.start;
 328         while (en_l < l_ptrs.end) {
 329                 if (extent_entry_type(en_l) == BCH_EXTENT_ENTRY_ptr &&
 330                     use_right_ptr)
 331                         en_l->ptr = en_r->ptr;
 332
 333                 if (extent_entry_is_crc(en_l)) {
 334                         struct bch_extent_crc_unpacked crc_l =
 335                                 bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
 336                         struct bch_extent_crc_unpacked crc_r =
 337                                 bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
 338
 339                         use_right_ptr = false;
 340
 341                         if (crc_l.offset + crc_l.live_size + crc_r.live_size <=
 342                             crc_l.uncompressed_size) {
 343                                 /* can use left extent's crc entry */
 344                         } else if (crc_l.live_size <= crc_r.offset) {
 345                                 /* can use right extent's crc entry */
 346                                 crc_r.offset -= crc_l.live_size;
 347                                 bch2_extent_crc_pack(entry_to_crc(en_l), crc_r,
 348                                                      extent_entry_type(en_l));
 349                                 use_right_ptr = true;
 350                         } else {
 351                                 crc_l.csum = bch2_checksum_merge(crc_l.csum_type,
 352                                                                  crc_l.csum,
 353                                                                  crc_r.csum,
 354                                                                  crc_r.uncompressed_size << 9);
 355
 356                                 crc_l.uncompressed_size += crc_r.uncompressed_size;
 357                                 crc_l.compressed_size   += crc_r.compressed_size;
 358                                 bch2_extent_crc_pack(entry_to_crc(en_l), crc_l,
 359                                                      extent_entry_type(en_l));
 360                         }
 361                 }
 362
 363                 en_l = extent_entry_next(en_l);
 364                 en_r = extent_entry_next(en_r);
 365         }
 366
 367         bch2_key_resize(l.k, l.k->size + r.k->size);
 368         return true;
 369 }
 370
 371 /* KEY_TYPE_reservation: */
 372
 373 int bch2_reservation_invalid(const struct bch_fs *c, struct bkey_s_c k,
 374                              unsigned flags, struct printbuf *err)
 375 {
 376         struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
 377
 378         if (!r.v->nr_replicas || r.v->nr_replicas > BCH_REPLICAS_MAX) {
 379                 prt_printf(err, "invalid nr_replicas (%u)",
 380                        r.v->nr_replicas);
 381                 return -BCH_ERR_invalid_bkey;
 382         }
 383
 384         return 0;
 385 }
 386
 387 void bch2_reservation_to_text(struct printbuf *out, struct bch_fs *c,
 388                               struct bkey_s_c k)
 389 {
 390         struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
 391
 392         prt_printf(out, "generation %u replicas %u",
 393                le32_to_cpu(r.v->generation),
 394                r.v->nr_replicas);
 395 }
 396
 397 bool bch2_reservation_merge(struct bch_fs *c, struct bkey_s _l, struct bkey_s_c _r)
 398 {
 399         struct bkey_s_reservation l = bkey_s_to_reservation(_l);
 400         struct bkey_s_c_reservation r = bkey_s_c_to_reservation(_r);
 401
 402         if (l.v->generation != r.v->generation ||
 403             l.v->nr_replicas != r.v->nr_replicas)
 404                 return false;
 405
 406         bch2_key_resize(l.k, l.k->size + r.k->size);
 407         return true;
 408 }
 409
 410 /* Extent checksum entries: */
 411
 412 /* returns true if not equal */
 413 static inline bool bch2_crc_unpacked_cmp(struct bch_extent_crc_unpacked l,
 414                                          struct bch_extent_crc_unpacked r)
 415 {
 416         return (l.csum_type             != r.csum_type ||
 417                 l.compression_type      != r.compression_type ||
 418                 l.compressed_size       != r.compressed_size ||
 419                 l.uncompressed_size     != r.uncompressed_size ||
 420                 l.offset                != r.offset ||
 421                 l.live_size             != r.live_size ||
 422                 l.nonce                 != r.nonce ||
 423                 bch2_crc_cmp(l.csum, r.csum));
 424 }
 425
 426 static inline bool can_narrow_crc(struct bch_extent_crc_unpacked u,
 427                                   struct bch_extent_crc_unpacked n)
 428 {
 429         return !crc_is_compressed(u) &&
 430                 u.csum_type &&
 431                 u.uncompressed_size > u.live_size &&
 432                 bch2_csum_type_is_encryption(u.csum_type) ==
 433                 bch2_csum_type_is_encryption(n.csum_type);
 434 }
 435
 436 bool bch2_can_narrow_extent_crcs(struct bkey_s_c k,
 437                                  struct bch_extent_crc_unpacked n)
 438 {
 439         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 440         struct bch_extent_crc_unpacked crc;
 441         const union bch_extent_entry *i;
 442
 443         if (!n.csum_type)
 444                 return false;
 445
 446         bkey_for_each_crc(k.k, ptrs, crc, i)
 447                 if (can_narrow_crc(crc, n))
 448                         return true;
 449
 450         return false;
 451 }
 452
 453 /*
 454  * We're writing another replica for this extent, so while we've got the data in
 455  * memory we'll be computing a new checksum for the currently live data.
 456  *
 457  * If there are other replicas we aren't moving, and they are checksummed but
 458  * not compressed, we can modify them to point to only the data that is
 459  * currently live (so that readers won't have to bounce) while we've got the
 460  * checksum we need:
 461  */
 462 bool bch2_bkey_narrow_crcs(struct bkey_i *k, struct bch_extent_crc_unpacked n)
 463 {
 464         struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 465         struct bch_extent_crc_unpacked u;
 466         struct extent_ptr_decoded p;
 467         union bch_extent_entry *i;
 468         bool ret = false;
 469
 470         /* Find a checksum entry that covers only live data: */
 471         if (!n.csum_type) {
 472                 bkey_for_each_crc(&k->k, ptrs, u, i)
 473                         if (!crc_is_compressed(u) &&
 474                             u.csum_type &&
 475                             u.live_size == u.uncompressed_size) {
 476                                 n = u;
 477                                 goto found;
 478                         }
 479                 return false;
 480         }
 481 found:
 482         BUG_ON(crc_is_compressed(n));
 483         BUG_ON(n.offset);
 484         BUG_ON(n.live_size != k->k.size);
 485
 486 restart_narrow_pointers:
 487         ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 488
 489         bkey_for_each_ptr_decode(&k->k, ptrs, p, i)
 490                 if (can_narrow_crc(p.crc, n)) {
 491                         bch2_bkey_drop_ptr_noerror(bkey_i_to_s(k), &i->ptr);
 492                         p.ptr.offset += p.crc.offset;
 493                         p.crc = n;
 494                         bch2_extent_ptr_decoded_append(k, &p);
 495                         ret = true;
 496                         goto restart_narrow_pointers;
 497                 }
 498
 499         return ret;
 500 }
 501
 502 static void bch2_extent_crc_pack(union bch_extent_crc *dst,
 503                                  struct bch_extent_crc_unpacked src,
 504                                  enum bch_extent_entry_type type)
 505 {
 506 #define set_common_fields(_dst, _src)                                   \
 507                 _dst.type               = 1 << type;                    \
 508                 _dst.csum_type          = _src.csum_type,               \
 509                 _dst.compression_type   = _src.compression_type,        \
 510                 _dst._compressed_size   = _src.compressed_size - 1,     \
 511                 _dst._uncompressed_size = _src.uncompressed_size - 1,   \
 512                 _dst.offset             = _src.offset
 513
 514         switch (type) {
 515         case BCH_EXTENT_ENTRY_crc32:
 516                 set_common_fields(dst->crc32, src);
 517                 dst->crc32.csum  = *((__le32 *) &src.csum.lo);
 518                 break;
 519         case BCH_EXTENT_ENTRY_crc64:
 520                 set_common_fields(dst->crc64, src);
 521                 dst->crc64.nonce        = src.nonce;
 522                 dst->crc64.csum_lo      = src.csum.lo;
 523                 dst->crc64.csum_hi      = *((__le16 *) &src.csum.hi);
 524                 break;
 525         case BCH_EXTENT_ENTRY_crc128:
 526                 set_common_fields(dst->crc128, src);
 527                 dst->crc128.nonce       = src.nonce;
 528                 dst->crc128.csum        = src.csum;
 529                 break;
 530         default:
 531                 BUG();
 532         }
 533 #undef set_common_fields
 534 }
 535
 536 void bch2_extent_crc_append(struct bkey_i *k,
 537                             struct bch_extent_crc_unpacked new)
 538 {
 539         struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 540         union bch_extent_crc *crc = (void *) ptrs.end;
 541         enum bch_extent_entry_type type;
 542
 543         if (bch_crc_bytes[new.csum_type]        <= 4 &&
 544             new.uncompressed_size               <= CRC32_SIZE_MAX &&
 545             new.nonce                           <= CRC32_NONCE_MAX)
 546                 type = BCH_EXTENT_ENTRY_crc32;
 547         else if (bch_crc_bytes[new.csum_type]   <= 10 &&
 548                    new.uncompressed_size        <= CRC64_SIZE_MAX &&
 549                    new.nonce                    <= CRC64_NONCE_MAX)
 550                 type = BCH_EXTENT_ENTRY_crc64;
 551         else if (bch_crc_bytes[new.csum_type]   <= 16 &&
 552                    new.uncompressed_size        <= CRC128_SIZE_MAX &&
 553                    new.nonce                    <= CRC128_NONCE_MAX)
 554                 type = BCH_EXTENT_ENTRY_crc128;
 555         else
 556                 BUG();
 557
 558         bch2_extent_crc_pack(crc, new, type);
 559
 560         k->k.u64s += extent_entry_u64s(ptrs.end);
 561
 562         EBUG_ON(bkey_val_u64s(&k->k) > BKEY_EXTENT_VAL_U64s_MAX);
 563 }
 564
 565 /* Generic code for keys with pointers: */
 566
 567 unsigned bch2_bkey_nr_ptrs(struct bkey_s_c k)
 568 {
 569         return bch2_bkey_devs(k).nr;
 570 }
 571
 572 unsigned bch2_bkey_nr_ptrs_allocated(struct bkey_s_c k)
 573 {
 574         return k.k->type == KEY_TYPE_reservation
 575                 ? bkey_s_c_to_reservation(k).v->nr_replicas
 576                 : bch2_bkey_dirty_devs(k).nr;
 577 }
 578
 579 unsigned bch2_bkey_nr_ptrs_fully_allocated(struct bkey_s_c k)
 580 {
 581         unsigned ret = 0;
 582
 583         if (k.k->type == KEY_TYPE_reservation) {
 584                 ret = bkey_s_c_to_reservation(k).v->nr_replicas;
 585         } else {
 586                 struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 587                 const union bch_extent_entry *entry;
 588                 struct extent_ptr_decoded p;
 589
 590                 bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 591                         ret += !p.ptr.cached && !crc_is_compressed(p.crc);
 592         }
 593
 594         return ret;
 595 }
 596
 597 unsigned bch2_bkey_sectors_compressed(struct bkey_s_c k)
 598 {
 599         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 600         const union bch_extent_entry *entry;
 601         struct extent_ptr_decoded p;
 602         unsigned ret = 0;
 603
 604         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 605                 if (!p.ptr.cached && crc_is_compressed(p.crc))
 606                         ret += p.crc.compressed_size;
 607
 608         return ret;
 609 }
 610
 611 bool bch2_bkey_is_incompressible(struct bkey_s_c k)
 612 {
 613         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 614         const union bch_extent_entry *entry;
 615         struct bch_extent_crc_unpacked crc;
 616
 617         bkey_for_each_crc(k.k, ptrs, crc, entry)
 618                 if (crc.compression_type == BCH_COMPRESSION_TYPE_incompressible)
 619                         return true;
 620         return false;
 621 }
 622
 623 unsigned bch2_bkey_replicas(struct bch_fs *c, struct bkey_s_c k)
 624 {
 625         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 626         const union bch_extent_entry *entry;
 627         struct extent_ptr_decoded p = { 0 };
 628         unsigned replicas = 0;
 629
 630         bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
 631                 if (p.ptr.cached)
 632                         continue;
 633
 634                 if (p.has_ec)
 635                         replicas += p.ec.redundancy;
 636
 637                 replicas++;
 638
 639         }
 640
 641         return replicas;
 642 }
 643
 644 unsigned bch2_extent_ptr_desired_durability(struct bch_fs *c, struct extent_ptr_decoded *p)
 645 {
 646         struct bch_dev *ca;
 647
 648         if (p->ptr.cached)
 649                 return 0;
 650
 651         ca = bch_dev_bkey_exists(c, p->ptr.dev);
 652
 653         return ca->mi.durability +
 654                 (p->has_ec
 655                  ? p->ec.redundancy
 656                  : 0);
 657 }
 658
 659 unsigned bch2_extent_ptr_durability(struct bch_fs *c, struct extent_ptr_decoded *p)
 660 {
 661         struct bch_dev *ca;
 662
 663         if (p->ptr.cached)
 664                 return 0;
 665
 666         ca = bch_dev_bkey_exists(c, p->ptr.dev);
 667
 668         if (ca->mi.state == BCH_MEMBER_STATE_failed)
 669                 return 0;
 670
 671         return ca->mi.durability +
 672                 (p->has_ec
 673                  ? p->ec.redundancy
 674                  : 0);
 675 }
 676
 677 unsigned bch2_bkey_durability(struct bch_fs *c, struct bkey_s_c k)
 678 {
 679         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 680         const union bch_extent_entry *entry;
 681         struct extent_ptr_decoded p;
 682         unsigned durability = 0;
 683
 684         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 685                 durability += bch2_extent_ptr_durability(c, &p);
 686
 687         return durability;
 688 }
 689
 690 static unsigned bch2_bkey_durability_safe(struct bch_fs *c, struct bkey_s_c k)
 691 {
 692         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 693         const union bch_extent_entry *entry;
 694         struct extent_ptr_decoded p;
 695         unsigned durability = 0;
 696
 697         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 698                 if (p.ptr.dev < c->sb.nr_devices && c->devs[p.ptr.dev])
 699                         durability += bch2_extent_ptr_durability(c, &p);
 700
 701         return durability;
 702 }
 703
 704 void bch2_bkey_extent_entry_drop(struct bkey_i *k, union bch_extent_entry *entry)
 705 {
 706         union bch_extent_entry *end = bkey_val_end(bkey_i_to_s(k));
 707         union bch_extent_entry *next = extent_entry_next(entry);
 708
 709         memmove_u64s(entry, next, (u64 *) end - (u64 *) next);
 710         k->k.u64s -= extent_entry_u64s(entry);
 711 }
 712
 713 void bch2_extent_ptr_decoded_append(struct bkey_i *k,
 714                                     struct extent_ptr_decoded *p)
 715 {
 716         struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 717         struct bch_extent_crc_unpacked crc =
 718                 bch2_extent_crc_unpack(&k->k, NULL);
 719         union bch_extent_entry *pos;
 720
 721         if (!bch2_crc_unpacked_cmp(crc, p->crc)) {
 722                 pos = ptrs.start;
 723                 goto found;
 724         }
 725
 726         bkey_for_each_crc(&k->k, ptrs, crc, pos)
 727                 if (!bch2_crc_unpacked_cmp(crc, p->crc)) {
 728                         pos = extent_entry_next(pos);
 729                         goto found;
 730                 }
 731
 732         bch2_extent_crc_append(k, p->crc);
 733         pos = bkey_val_end(bkey_i_to_s(k));
 734 found:
 735         p->ptr.type = 1 << BCH_EXTENT_ENTRY_ptr;
 736         __extent_entry_insert(k, pos, to_entry(&p->ptr));
 737
 738         if (p->has_ec) {
 739                 p->ec.type = 1 << BCH_EXTENT_ENTRY_stripe_ptr;
 740                 __extent_entry_insert(k, pos, to_entry(&p->ec));
 741         }
 742 }
 743
 744 static union bch_extent_entry *extent_entry_prev(struct bkey_ptrs ptrs,
 745                                           union bch_extent_entry *entry)
 746 {
 747         union bch_extent_entry *i = ptrs.start;
 748
 749         if (i == entry)
 750                 return NULL;
 751
 752         while (extent_entry_next(i) != entry)
 753                 i = extent_entry_next(i);
 754         return i;
 755 }
 756
 757 static void extent_entry_drop(struct bkey_s k, union bch_extent_entry *entry)
 758 {
 759         union bch_extent_entry *next = extent_entry_next(entry);
 760
 761         /* stripes have ptrs, but their layout doesn't work with this code */
 762         BUG_ON(k.k->type == KEY_TYPE_stripe);
 763
 764         memmove_u64s_down(entry, next,
 765                           (u64 *) bkey_val_end(k) - (u64 *) next);
 766         k.k->u64s -= (u64 *) next - (u64 *) entry;
 767 }
 768
 769 /*
 770  * Returns pointer to the next entry after the one being dropped:
 771  */
 772 union bch_extent_entry *bch2_bkey_drop_ptr_noerror(struct bkey_s k,
 773                                                    struct bch_extent_ptr *ptr)
 774 {
 775         struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
 776         union bch_extent_entry *entry = to_entry(ptr), *next;
 777         union bch_extent_entry *ret = entry;
 778         bool drop_crc = true;
 779
 780         EBUG_ON(ptr < &ptrs.start->ptr ||
 781                 ptr >= &ptrs.end->ptr);
 782         EBUG_ON(ptr->type != 1 << BCH_EXTENT_ENTRY_ptr);
 783
 784         for (next = extent_entry_next(entry);
 785              next != ptrs.end;
 786              next = extent_entry_next(next)) {
 787                 if (extent_entry_is_crc(next)) {
 788                         break;
 789                 } else if (extent_entry_is_ptr(next)) {
 790                         drop_crc = false;
 791                         break;
 792                 }
 793         }
 794
 795         extent_entry_drop(k, entry);
 796
 797         while ((entry = extent_entry_prev(ptrs, entry))) {
 798                 if (extent_entry_is_ptr(entry))
 799                         break;
 800
 801                 if ((extent_entry_is_crc(entry) && drop_crc) ||
 802                     extent_entry_is_stripe_ptr(entry)) {
 803                         ret = (void *) ret - extent_entry_bytes(entry);
 804                         extent_entry_drop(k, entry);
 805                 }
 806         }
 807
 808         return ret;
 809 }
 810
 811 union bch_extent_entry *bch2_bkey_drop_ptr(struct bkey_s k,
 812                                            struct bch_extent_ptr *ptr)
 813 {
 814         bool have_dirty = bch2_bkey_dirty_devs(k.s_c).nr;
 815         union bch_extent_entry *ret =
 816                 bch2_bkey_drop_ptr_noerror(k, ptr);
 817
 818         /*
 819          * If we deleted all the dirty pointers and there's still cached
 820          * pointers, we could set the cached pointers to dirty if they're not
 821          * stale - but to do that correctly we'd need to grab an open_bucket
 822          * reference so that we don't race with bucket reuse:
 823          */
 824         if (have_dirty &&
 825             !bch2_bkey_dirty_devs(k.s_c).nr) {
 826                 k.k->type = KEY_TYPE_error;
 827                 set_bkey_val_u64s(k.k, 0);
 828                 ret = NULL;
 829         } else if (!bch2_bkey_nr_ptrs(k.s_c)) {
 830                 k.k->type = KEY_TYPE_deleted;
 831                 set_bkey_val_u64s(k.k, 0);
 832                 ret = NULL;
 833         }
 834
 835         return ret;
 836 }
 837
 838 void bch2_bkey_drop_device(struct bkey_s k, unsigned dev)
 839 {
 840         struct bch_extent_ptr *ptr;
 841
 842         bch2_bkey_drop_ptrs(k, ptr, ptr->dev == dev);
 843 }
 844
 845 void bch2_bkey_drop_device_noerror(struct bkey_s k, unsigned dev)
 846 {
 847         struct bch_extent_ptr *ptr = bch2_bkey_has_device(k, dev);
 848
 849         if (ptr)
 850                 bch2_bkey_drop_ptr_noerror(k, ptr);
 851 }
 852
 853 const struct bch_extent_ptr *bch2_bkey_has_device_c(struct bkey_s_c k, unsigned dev)
 854 {
 855         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 856         const struct bch_extent_ptr *ptr;
 857
 858         bkey_for_each_ptr(ptrs, ptr)
 859                 if (ptr->dev == dev)
 860                         return ptr;
 861
 862         return NULL;
 863 }
 864
 865 bool bch2_bkey_has_target(struct bch_fs *c, struct bkey_s_c k, unsigned target)
 866 {
 867         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 868         const struct bch_extent_ptr *ptr;
 869
 870         bkey_for_each_ptr(ptrs, ptr)
 871                 if (bch2_dev_in_target(c, ptr->dev, target) &&
 872                     (!ptr->cached ||
 873                      !ptr_stale(bch_dev_bkey_exists(c, ptr->dev), ptr)))
 874                         return true;
 875
 876         return false;
 877 }
 878
 879 bool bch2_bkey_matches_ptr(struct bch_fs *c, struct bkey_s_c k,
 880                            struct bch_extent_ptr m, u64 offset)
 881 {
 882         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 883         const union bch_extent_entry *entry;
 884         struct extent_ptr_decoded p;
 885
 886         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 887                 if (p.ptr.dev   == m.dev &&
 888                     p.ptr.gen   == m.gen &&
 889                     (s64) p.ptr.offset + p.crc.offset - bkey_start_offset(k.k) ==
 890                     (s64) m.offset  - offset)
 891                         return true;
 892
 893         return false;
 894 }
 895
 896 /*
 897  * Returns true if two extents refer to the same data:
 898  */
 899 bool bch2_extents_match(struct bkey_s_c k1, struct bkey_s_c k2)
 900 {
 901         if (k1.k->type != k2.k->type)
 902                 return false;
 903
 904         if (bkey_extent_is_direct_data(k1.k)) {
 905                 struct bkey_ptrs_c ptrs1 = bch2_bkey_ptrs_c(k1);
 906                 struct bkey_ptrs_c ptrs2 = bch2_bkey_ptrs_c(k2);
 907                 const union bch_extent_entry *entry1, *entry2;
 908                 struct extent_ptr_decoded p1, p2;
 909
 910                 if (bkey_extent_is_unwritten(k1) != bkey_extent_is_unwritten(k2))
 911                         return false;
 912
 913                 bkey_for_each_ptr_decode(k1.k, ptrs1, p1, entry1)
 914                         bkey_for_each_ptr_decode(k2.k, ptrs2, p2, entry2)
 915                         if (p1.ptr.dev          == p2.ptr.dev &&
 916                             p1.ptr.gen          == p2.ptr.gen &&
 917                             (s64) p1.ptr.offset + p1.crc.offset - bkey_start_offset(k1.k) ==
 918                             (s64) p2.ptr.offset + p2.crc.offset - bkey_start_offset(k2.k))
 919                                 return true;
 920
 921                 return false;
 922         } else {
 923                 /* KEY_TYPE_deleted, etc. */
 924                 return true;
 925         }
 926 }
 927
 928 struct bch_extent_ptr *
 929 bch2_extent_has_ptr(struct bkey_s_c k1, struct extent_ptr_decoded p1, struct bkey_s k2)
 930 {
 931         struct bkey_ptrs ptrs2 = bch2_bkey_ptrs(k2);
 932         union bch_extent_entry *entry2;
 933         struct extent_ptr_decoded p2;
 934
 935         bkey_for_each_ptr_decode(k2.k, ptrs2, p2, entry2)
 936                 if (p1.ptr.dev          == p2.ptr.dev &&
 937                     p1.ptr.gen          == p2.ptr.gen &&
 938                     (s64) p1.ptr.offset + p1.crc.offset - bkey_start_offset(k1.k) ==
 939                     (s64) p2.ptr.offset + p2.crc.offset - bkey_start_offset(k2.k))
 940                         return &entry2->ptr;
 941
 942         return NULL;
 943 }
 944
 945 void bch2_extent_ptr_set_cached(struct bkey_s k, struct bch_extent_ptr *ptr)
 946 {
 947         struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
 948         union bch_extent_entry *entry;
 949         union bch_extent_entry *ec = NULL;
 950
 951         bkey_extent_entry_for_each(ptrs, entry) {
 952                 if (&entry->ptr == ptr) {
 953                         ptr->cached = true;
 954                         if (ec)
 955                                 extent_entry_drop(k, ec);
 956                         return;
 957                 }
 958
 959                 if (extent_entry_is_stripe_ptr(entry))
 960                         ec = entry;
 961                 else if (extent_entry_is_ptr(entry))
 962                         ec = NULL;
 963         }
 964
 965         BUG();
 966 }
 967
 968 /*
 969  * bch_extent_normalize - clean up an extent, dropping stale pointers etc.
 970  *
 971  * Returns true if @k should be dropped entirely
 972  *
 973  * For existing keys, only called when btree nodes are being rewritten, not when
 974  * they're merely being compacted/resorted in memory.
 975  */
 976 bool bch2_extent_normalize(struct bch_fs *c, struct bkey_s k)
 977 {
 978         struct bch_extent_ptr *ptr;
 979
 980         bch2_bkey_drop_ptrs(k, ptr,
 981                 ptr->cached &&
 982                 ptr_stale(bch_dev_bkey_exists(c, ptr->dev), ptr));
 983
 984         return bkey_deleted(k.k);
 985 }
 986
 987 void bch2_bkey_ptrs_to_text(struct printbuf *out, struct bch_fs *c,
 988                             struct bkey_s_c k)
 989 {
 990         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 991         const union bch_extent_entry *entry;
 992         struct bch_extent_crc_unpacked crc;
 993         const struct bch_extent_ptr *ptr;
 994         const struct bch_extent_stripe_ptr *ec;
 995         struct bch_dev *ca;
 996         bool first = true;
 997
 998         if (c)
 999                 prt_printf(out, "durability: %u ", bch2_bkey_durability_safe(c, k));
1000
1001         bkey_extent_entry_for_each(ptrs, entry) {
1002                 if (!first)
1003                         prt_printf(out, " ");
1004
1005                 switch (__extent_entry_type(entry)) {
1006                 case BCH_EXTENT_ENTRY_ptr:
1007                         ptr = entry_to_ptr(entry);
1008                         ca = c && ptr->dev < c->sb.nr_devices && c->devs[ptr->dev]
1009                                 ? bch_dev_bkey_exists(c, ptr->dev)
1010                                 : NULL;
1011
1012                         if (!ca) {
1013                                 prt_printf(out, "ptr: %u:%llu gen %u%s", ptr->dev,
1014                                        (u64) ptr->offset, ptr->gen,
1015                                        ptr->cached ? " cached" : "");
1016                         } else {
1017                                 u32 offset;
1018                                 u64 b = sector_to_bucket_and_offset(ca, ptr->offset, &offset);
1019
1020                                 prt_printf(out, "ptr: %u:%llu:%u gen %u",
1021                                            ptr->dev, b, offset, ptr->gen);
1022                                 if (ptr->cached)
1023                                         prt_str(out, " cached");
1024                                 if (ptr->unwritten)
1025                                         prt_str(out, " unwritten");
1026                                 if (ca && ptr_stale(ca, ptr))
1027                                         prt_printf(out, " stale");
1028                         }
1029                         break;
1030                 case BCH_EXTENT_ENTRY_crc32:
1031                 case BCH_EXTENT_ENTRY_crc64:
1032                 case BCH_EXTENT_ENTRY_crc128:
1033                         crc = bch2_extent_crc_unpack(k.k, entry_to_crc(entry));
1034
1035                         prt_printf(out, "crc: c_size %u size %u offset %u nonce %u csum %s compress %s",
1036                                crc.compressed_size,
1037                                crc.uncompressed_size,
1038                                crc.offset, crc.nonce,
1039                                bch2_csum_types[crc.csum_type],
1040                                bch2_compression_types[crc.compression_type]);
1041                         break;
1042                 case BCH_EXTENT_ENTRY_stripe_ptr:
1043                         ec = &entry->stripe_ptr;
1044
1045                         prt_printf(out, "ec: idx %llu block %u",
1046                                (u64) ec->idx, ec->block);
1047                         break;
1048                 default:
1049                         prt_printf(out, "(invalid extent entry %.16llx)", *((u64 *) entry));
1050                         return;
1051                 }
1052
1053                 first = false;
1054         }
1055 }
1056
1057 static int extent_ptr_invalid(const struct bch_fs *c,
1058                               struct bkey_s_c k,
1059                               const struct bch_extent_ptr *ptr,
1060                               unsigned size_ondisk,
1061                               bool metadata,
1062                               struct printbuf *err)
1063 {
1064         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1065         const struct bch_extent_ptr *ptr2;
1066         u64 bucket;
1067         u32 bucket_offset;
1068         struct bch_dev *ca;
1069
1070         if (!bch2_dev_exists2(c, ptr->dev)) {
1071                 prt_printf(err, "pointer to invalid device (%u)", ptr->dev);
1072                 return -BCH_ERR_invalid_bkey;
1073         }
1074
1075         ca = bch_dev_bkey_exists(c, ptr->dev);
1076         bkey_for_each_ptr(ptrs, ptr2)
1077                 if (ptr != ptr2 && ptr->dev == ptr2->dev) {
1078                         prt_printf(err, "multiple pointers to same device (%u)", ptr->dev);
1079                         return -BCH_ERR_invalid_bkey;
1080                 }
1081
1082         bucket = sector_to_bucket_and_offset(ca, ptr->offset, &bucket_offset);
1083
1084         if (bucket >= ca->mi.nbuckets) {
1085                 prt_printf(err, "pointer past last bucket (%llu > %llu)",
1086                        bucket, ca->mi.nbuckets);
1087                 return -BCH_ERR_invalid_bkey;
1088         }
1089
1090         if (ptr->offset < bucket_to_sector(ca, ca->mi.first_bucket)) {
1091                 prt_printf(err, "pointer before first bucket (%llu < %u)",
1092                        bucket, ca->mi.first_bucket);
1093                 return -BCH_ERR_invalid_bkey;
1094         }
1095
1096         if (bucket_offset + size_ondisk > ca->mi.bucket_size) {
1097                 prt_printf(err, "pointer spans multiple buckets (%u + %u > %u)",
1098                        bucket_offset, size_ondisk, ca->mi.bucket_size);
1099                 return -BCH_ERR_invalid_bkey;
1100         }
1101
1102         return 0;
1103 }
1104
1105 int bch2_bkey_ptrs_invalid(const struct bch_fs *c, struct bkey_s_c k,
1106                            unsigned flags, struct printbuf *err)
1107 {
1108         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1109         const union bch_extent_entry *entry;
1110         struct bch_extent_crc_unpacked crc;
1111         unsigned size_ondisk = k.k->size;
1112         unsigned nonce = UINT_MAX;
1113         unsigned nr_ptrs = 0;
1114         bool unwritten = false, have_ec = false, crc_since_last_ptr = false;
1115         int ret;
1116
1117         if (bkey_is_btree_ptr(k.k))
1118                 size_ondisk = btree_sectors(c);
1119
1120         bkey_extent_entry_for_each(ptrs, entry) {
1121                 if (__extent_entry_type(entry) >= BCH_EXTENT_ENTRY_MAX) {
1122                         prt_printf(err, "invalid extent entry type (got %u, max %u)",
1123                                __extent_entry_type(entry), BCH_EXTENT_ENTRY_MAX);
1124                         return -BCH_ERR_invalid_bkey;
1125                 }
1126
1127                 if (bkey_is_btree_ptr(k.k) &&
1128                     !extent_entry_is_ptr(entry)) {
1129                         prt_printf(err, "has non ptr field");
1130                         return -BCH_ERR_invalid_bkey;
1131                 }
1132
1133                 switch (extent_entry_type(entry)) {
1134                 case BCH_EXTENT_ENTRY_ptr:
1135                         ret = extent_ptr_invalid(c, k, &entry->ptr, size_ondisk,
1136                                                  false, err);
1137                         if (ret)
1138                                 return ret;
1139
1140                         if (nr_ptrs && unwritten != entry->ptr.unwritten) {
1141                                 prt_printf(err, "extent with unwritten and written ptrs");
1142                                 return -BCH_ERR_invalid_bkey;
1143                         }
1144
1145                         if (k.k->type != KEY_TYPE_extent && entry->ptr.unwritten) {
1146                                 prt_printf(err, "has unwritten ptrs");
1147                                 return -BCH_ERR_invalid_bkey;
1148                         }
1149
1150                         if (entry->ptr.cached && have_ec) {
1151                                 prt_printf(err, "cached, erasure coded ptr");
1152                                 return -BCH_ERR_invalid_bkey;
1153                         }
1154
1155                         unwritten = entry->ptr.unwritten;
1156                         have_ec = false;
1157                         crc_since_last_ptr = false;
1158                         nr_ptrs++;
1159                         break;
1160                 case BCH_EXTENT_ENTRY_crc32:
1161                 case BCH_EXTENT_ENTRY_crc64:
1162                 case BCH_EXTENT_ENTRY_crc128:
1163                         crc = bch2_extent_crc_unpack(k.k, entry_to_crc(entry));
1164
1165                         if (crc.offset + crc.live_size >
1166                             crc.uncompressed_size) {
1167                                 prt_printf(err, "checksum offset + key size > uncompressed size");
1168                                 return -BCH_ERR_invalid_bkey;
1169                         }
1170
1171                         size_ondisk = crc.compressed_size;
1172
1173                         if (!bch2_checksum_type_valid(c, crc.csum_type)) {
1174                                 prt_printf(err, "invalid checksum type");
1175                                 return -BCH_ERR_invalid_bkey;
1176                         }
1177
1178                         if (crc.compression_type >= BCH_COMPRESSION_TYPE_NR) {
1179                                 prt_printf(err, "invalid compression type");
1180                                 return -BCH_ERR_invalid_bkey;
1181                         }
1182
1183                         if (bch2_csum_type_is_encryption(crc.csum_type)) {
1184                                 if (nonce == UINT_MAX)
1185                                         nonce = crc.offset + crc.nonce;
1186                                 else if (nonce != crc.offset + crc.nonce) {
1187                                         prt_printf(err, "incorrect nonce");
1188                                         return -BCH_ERR_invalid_bkey;
1189                                 }
1190                         }
1191
1192                         if (crc_since_last_ptr) {
1193                                 prt_printf(err, "redundant crc entry");
1194                                 return -BCH_ERR_invalid_bkey;
1195                         }
1196                         crc_since_last_ptr = true;
1197                         break;
1198                 case BCH_EXTENT_ENTRY_stripe_ptr:
1199                         if (have_ec) {
1200                                 prt_printf(err, "redundant stripe entry");
1201                                 return -BCH_ERR_invalid_bkey;
1202                         }
1203                         have_ec = true;
1204                         break;
1205                 }
1206         }
1207
1208         if (!nr_ptrs) {
1209                 prt_str(err, "no ptrs");
1210                 return -BCH_ERR_invalid_bkey;
1211         }
1212
1213         if (nr_ptrs >= BCH_BKEY_PTRS_MAX) {
1214                 prt_str(err, "too many ptrs");
1215                 return -BCH_ERR_invalid_bkey;
1216         }
1217
1218         if (crc_since_last_ptr) {
1219                 prt_printf(err, "redundant crc entry");
1220                 return -BCH_ERR_invalid_bkey;
1221         }
1222
1223         if (have_ec) {
1224                 prt_printf(err, "redundant stripe entry");
1225                 return -BCH_ERR_invalid_bkey;
1226         }
1227
1228         return 0;
1229 }
1230
1231 void bch2_ptr_swab(struct bkey_s k)
1232 {
1233         struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
1234         union bch_extent_entry *entry;
1235         u64 *d;
1236
1237         for (d =  (u64 *) ptrs.start;
1238              d != (u64 *) ptrs.end;
1239              d++)
1240                 *d = swab64(*d);
1241
1242         for (entry = ptrs.start;
1243              entry < ptrs.end;
1244              entry = extent_entry_next(entry)) {
1245                 switch (extent_entry_type(entry)) {
1246                 case BCH_EXTENT_ENTRY_ptr:
1247                         break;
1248                 case BCH_EXTENT_ENTRY_crc32:
1249                         entry->crc32.csum = swab32(entry->crc32.csum);
1250                         break;
1251                 case BCH_EXTENT_ENTRY_crc64:
1252                         entry->crc64.csum_hi = swab16(entry->crc64.csum_hi);
1253                         entry->crc64.csum_lo = swab64(entry->crc64.csum_lo);
1254                         break;
1255                 case BCH_EXTENT_ENTRY_crc128:
1256                         entry->crc128.csum.hi = (__force __le64)
1257                                 swab64((__force u64) entry->crc128.csum.hi);
1258                         entry->crc128.csum.lo = (__force __le64)
1259                                 swab64((__force u64) entry->crc128.csum.lo);
1260                         break;
1261                 case BCH_EXTENT_ENTRY_stripe_ptr:
1262                         break;
1263                 }
1264         }
1265 }
1266
1267 /* Generic extent code: */
1268
1269 int bch2_cut_front_s(struct bpos where, struct bkey_s k)
1270 {
1271         unsigned new_val_u64s = bkey_val_u64s(k.k);
1272         int val_u64s_delta;
1273         u64 sub;
1274
1275         if (bkey_le(where, bkey_start_pos(k.k)))
1276                 return 0;
1277
1278         EBUG_ON(bkey_gt(where, k.k->p));
1279
1280         sub = where.offset - bkey_start_offset(k.k);
1281
1282         k.k->size -= sub;
1283
1284         if (!k.k->size) {
1285                 k.k->type = KEY_TYPE_deleted;
1286                 new_val_u64s = 0;
1287         }
1288
1289         switch (k.k->type) {
1290         case KEY_TYPE_extent:
1291         case KEY_TYPE_reflink_v: {
1292                 struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
1293                 union bch_extent_entry *entry;
1294                 bool seen_crc = false;
1295
1296                 bkey_extent_entry_for_each(ptrs, entry) {
1297                         switch (extent_entry_type(entry)) {
1298                         case BCH_EXTENT_ENTRY_ptr:
1299                                 if (!seen_crc)
1300                                         entry->ptr.offset += sub;
1301                                 break;
1302                         case BCH_EXTENT_ENTRY_crc32:
1303                                 entry->crc32.offset += sub;
1304                                 break;
1305                         case BCH_EXTENT_ENTRY_crc64:
1306                                 entry->crc64.offset += sub;
1307                                 break;
1308                         case BCH_EXTENT_ENTRY_crc128:
1309                                 entry->crc128.offset += sub;
1310                                 break;
1311                         case BCH_EXTENT_ENTRY_stripe_ptr:
1312                                 break;
1313                         }
1314
1315                         if (extent_entry_is_crc(entry))
1316                                 seen_crc = true;
1317                 }
1318
1319                 break;
1320         }
1321         case KEY_TYPE_reflink_p: {
1322                 struct bkey_s_reflink_p p = bkey_s_to_reflink_p(k);
1323
1324                 le64_add_cpu(&p.v->idx, sub);
1325                 break;
1326         }
1327         case KEY_TYPE_inline_data:
1328         case KEY_TYPE_indirect_inline_data: {
1329                 void *p = bkey_inline_data_p(k);
1330                 unsigned bytes = bkey_inline_data_bytes(k.k);
1331
1332                 sub = min_t(u64, sub << 9, bytes);
1333
1334                 memmove(p, p + sub, bytes - sub);
1335
1336                 new_val_u64s -= sub >> 3;
1337                 break;
1338         }
1339         }
1340
1341         val_u64s_delta = bkey_val_u64s(k.k) - new_val_u64s;
1342         BUG_ON(val_u64s_delta < 0);
1343
1344         set_bkey_val_u64s(k.k, new_val_u64s);
1345         memset(bkey_val_end(k), 0, val_u64s_delta * sizeof(u64));
1346         return -val_u64s_delta;
1347 }
1348
1349 int bch2_cut_back_s(struct bpos where, struct bkey_s k)
1350 {
1351         unsigned new_val_u64s = bkey_val_u64s(k.k);
1352         int val_u64s_delta;
1353         u64 len = 0;
1354
1355         if (bkey_ge(where, k.k->p))
1356                 return 0;
1357
1358         EBUG_ON(bkey_lt(where, bkey_start_pos(k.k)));
1359
1360         len = where.offset - bkey_start_offset(k.k);
1361
1362         k.k->p.offset = where.offset;
1363         k.k->size = len;
1364
1365         if (!len) {
1366                 k.k->type = KEY_TYPE_deleted;
1367                 new_val_u64s = 0;
1368         }
1369
1370         switch (k.k->type) {
1371         case KEY_TYPE_inline_data:
1372         case KEY_TYPE_indirect_inline_data:
1373                 new_val_u64s = (bkey_inline_data_offset(k.k) +
1374                                 min(bkey_inline_data_bytes(k.k), k.k->size << 9)) >> 3;
1375                 break;
1376         }
1377
1378         val_u64s_delta = bkey_val_u64s(k.k) - new_val_u64s;
1379         BUG_ON(val_u64s_delta < 0);
1380
1381         set_bkey_val_u64s(k.k, new_val_u64s);
1382         memset(bkey_val_end(k), 0, val_u64s_delta * sizeof(u64));
1383         return -val_u64s_delta;
1384 }