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 "compress.h"
  17 #include "debug.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 "trace.h"
  27 #include "util.h"
  28
  29 static unsigned bch2_crc_field_size_max[] = {
  30         [BCH_EXTENT_ENTRY_crc32] = CRC32_SIZE_MAX,
  31         [BCH_EXTENT_ENTRY_crc64] = CRC64_SIZE_MAX,
  32         [BCH_EXTENT_ENTRY_crc128] = CRC128_SIZE_MAX,
  33 };
  34
  35 static void bch2_extent_crc_pack(union bch_extent_crc *,
  36                                  struct bch_extent_crc_unpacked,
  37                                  enum bch_extent_entry_type);
  38
  39 static struct bch_dev_io_failures *dev_io_failures(struct bch_io_failures *f,
  40                                                    unsigned dev)
  41 {
  42         struct bch_dev_io_failures *i;
  43
  44         for (i = f->devs; i < f->devs + f->nr; i++)
  45                 if (i->dev == dev)
  46                         return i;
  47
  48         return NULL;
  49 }
  50
  51 void bch2_mark_io_failure(struct bch_io_failures *failed,
  52                           struct extent_ptr_decoded *p)
  53 {
  54         struct bch_dev_io_failures *f = dev_io_failures(failed, p->ptr.dev);
  55
  56         if (!f) {
  57                 BUG_ON(failed->nr >= ARRAY_SIZE(failed->devs));
  58
  59                 f = &failed->devs[failed->nr++];
  60                 f->dev          = p->ptr.dev;
  61                 f->idx          = p->idx;
  62                 f->nr_failed    = 1;
  63                 f->nr_retries   = 0;
  64         } else if (p->idx != f->idx) {
  65                 f->idx          = p->idx;
  66                 f->nr_failed    = 1;
  67                 f->nr_retries   = 0;
  68         } else {
  69                 f->nr_failed++;
  70         }
  71 }
  72
  73 /*
  74  * returns true if p1 is better than p2:
  75  */
  76 static inline bool ptr_better(struct bch_fs *c,
  77                               const struct extent_ptr_decoded p1,
  78                               const struct extent_ptr_decoded p2)
  79 {
  80         if (likely(!p1.idx && !p2.idx)) {
  81                 struct bch_dev *dev1 = bch_dev_bkey_exists(c, p1.ptr.dev);
  82                 struct bch_dev *dev2 = bch_dev_bkey_exists(c, p2.ptr.dev);
  83
  84                 u64 l1 = atomic64_read(&dev1->cur_latency[READ]);
  85                 u64 l2 = atomic64_read(&dev2->cur_latency[READ]);
  86
  87                 /* Pick at random, biased in favor of the faster device: */
  88
  89                 return bch2_rand_range(l1 + l2) > l1;
  90         }
  91
  92         if (bch2_force_reconstruct_read)
  93                 return p1.idx > p2.idx;
  94
  95         return p1.idx < p2.idx;
  96 }
  97
  98 /*
  99  * This picks a non-stale pointer, preferably from a device other than @avoid.
 100  * Avoid can be NULL, meaning pick any. If there are no non-stale pointers to
 101  * other devices, it will still pick a pointer from avoid.
 102  */
 103 int bch2_bkey_pick_read_device(struct bch_fs *c, struct bkey_s_c k,
 104                                struct bch_io_failures *failed,
 105                                struct extent_ptr_decoded *pick)
 106 {
 107         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 108         const union bch_extent_entry *entry;
 109         struct extent_ptr_decoded p;
 110         struct bch_dev_io_failures *f;
 111         struct bch_dev *ca;
 112         int ret = 0;
 113
 114         if (k.k->type == KEY_TYPE_error)
 115                 return -EIO;
 116
 117         bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
 118                 /*
 119                  * Unwritten extent: no need to actually read, treat it as a
 120                  * hole and return 0s:
 121                  */
 122                 if (p.ptr.unwritten)
 123                         return 0;
 124
 125                 ca = bch_dev_bkey_exists(c, p.ptr.dev);
 126
 127                 /*
 128                  * If there are any dirty pointers it's an error if we can't
 129                  * read:
 130                  */
 131                 if (!ret && !p.ptr.cached)
 132                         ret = -EIO;
 133
 134                 if (p.ptr.cached && ptr_stale(ca, &p.ptr))
 135                         continue;
 136
 137                 f = failed ? dev_io_failures(failed, p.ptr.dev) : NULL;
 138                 if (f)
 139                         p.idx = f->nr_failed < f->nr_retries
 140                                 ? f->idx
 141                                 : f->idx + 1;
 142
 143                 if (!p.idx &&
 144                     !bch2_dev_is_readable(ca))
 145                         p.idx++;
 146
 147                 if (bch2_force_reconstruct_read &&
 148                     !p.idx && p.has_ec)
 149                         p.idx++;
 150
 151                 if (p.idx >= (unsigned) p.has_ec + 1)
 152                         continue;
 153
 154                 if (ret > 0 && !ptr_better(c, p, *pick))
 155                         continue;
 156
 157                 *pick = p;
 158                 ret = 1;
 159         }
 160
 161         return ret;
 162 }
 163
 164 /* KEY_TYPE_btree_ptr: */
 165
 166 int bch2_btree_ptr_invalid(struct bch_fs *c, struct bkey_s_c k,
 167                            enum bkey_invalid_flags flags,
 168                            struct printbuf *err)
 169 {
 170         int ret = 0;
 171
 172         bkey_fsck_err_on(bkey_val_u64s(k.k) > BCH_REPLICAS_MAX, c, err,
 173                          btree_ptr_val_too_big,
 174                          "value too big (%zu > %u)", bkey_val_u64s(k.k), BCH_REPLICAS_MAX);
 175
 176         ret = bch2_bkey_ptrs_invalid(c, k, flags, err);
 177 fsck_err:
 178         return ret;
 179 }
 180
 181 void bch2_btree_ptr_to_text(struct printbuf *out, struct bch_fs *c,
 182                             struct bkey_s_c k)
 183 {
 184         bch2_bkey_ptrs_to_text(out, c, k);
 185 }
 186
 187 int bch2_btree_ptr_v2_invalid(struct bch_fs *c, struct bkey_s_c k,
 188                               enum bkey_invalid_flags flags,
 189                               struct printbuf *err)
 190 {
 191         int ret = 0;
 192
 193         bkey_fsck_err_on(bkey_val_u64s(k.k) > BKEY_BTREE_PTR_VAL_U64s_MAX, c, err,
 194                          btree_ptr_v2_val_too_big,
 195                          "value too big (%zu > %zu)",
 196                          bkey_val_u64s(k.k), BKEY_BTREE_PTR_VAL_U64s_MAX);
 197
 198         ret = bch2_bkey_ptrs_invalid(c, k, flags, err);
 199 fsck_err:
 200         return ret;
 201 }
 202
 203 void bch2_btree_ptr_v2_to_text(struct printbuf *out, struct bch_fs *c,
 204                                struct bkey_s_c k)
 205 {
 206         struct bkey_s_c_btree_ptr_v2 bp = bkey_s_c_to_btree_ptr_v2(k);
 207
 208         prt_printf(out, "seq %llx written %u min_key %s",
 209                le64_to_cpu(bp.v->seq),
 210                le16_to_cpu(bp.v->sectors_written),
 211                BTREE_PTR_RANGE_UPDATED(bp.v) ? "R " : "");
 212
 213         bch2_bpos_to_text(out, bp.v->min_key);
 214         prt_printf(out, " ");
 215         bch2_bkey_ptrs_to_text(out, c, k);
 216 }
 217
 218 void bch2_btree_ptr_v2_compat(enum btree_id btree_id, unsigned version,
 219                               unsigned big_endian, int write,
 220                               struct bkey_s k)
 221 {
 222         struct bkey_s_btree_ptr_v2 bp = bkey_s_to_btree_ptr_v2(k);
 223
 224         compat_bpos(0, btree_id, version, big_endian, write, &bp.v->min_key);
 225
 226         if (version < bcachefs_metadata_version_inode_btree_change &&
 227             btree_id_is_extents(btree_id) &&
 228             !bkey_eq(bp.v->min_key, POS_MIN))
 229                 bp.v->min_key = write
 230                         ? bpos_nosnap_predecessor(bp.v->min_key)
 231                         : bpos_nosnap_successor(bp.v->min_key);
 232 }
 233
 234 /* KEY_TYPE_extent: */
 235
 236 bool bch2_extent_merge(struct bch_fs *c, struct bkey_s l, struct bkey_s_c r)
 237 {
 238         struct bkey_ptrs   l_ptrs = bch2_bkey_ptrs(l);
 239         struct bkey_ptrs_c r_ptrs = bch2_bkey_ptrs_c(r);
 240         union bch_extent_entry *en_l;
 241         const union bch_extent_entry *en_r;
 242         struct extent_ptr_decoded lp, rp;
 243         bool use_right_ptr;
 244         struct bch_dev *ca;
 245
 246         en_l = l_ptrs.start;
 247         en_r = r_ptrs.start;
 248         while (en_l < l_ptrs.end && en_r < r_ptrs.end) {
 249                 if (extent_entry_type(en_l) != extent_entry_type(en_r))
 250                         return false;
 251
 252                 en_l = extent_entry_next(en_l);
 253                 en_r = extent_entry_next(en_r);
 254         }
 255
 256         if (en_l < l_ptrs.end || en_r < r_ptrs.end)
 257                 return false;
 258
 259         en_l = l_ptrs.start;
 260         en_r = r_ptrs.start;
 261         lp.crc = bch2_extent_crc_unpack(l.k, NULL);
 262         rp.crc = bch2_extent_crc_unpack(r.k, NULL);
 263
 264         while (__bkey_ptr_next_decode(l.k, l_ptrs.end, lp, en_l) &&
 265                __bkey_ptr_next_decode(r.k, r_ptrs.end, rp, en_r)) {
 266                 if (lp.ptr.offset + lp.crc.offset + lp.crc.live_size !=
 267                     rp.ptr.offset + rp.crc.offset ||
 268                     lp.ptr.dev                  != rp.ptr.dev ||
 269                     lp.ptr.gen                  != rp.ptr.gen ||
 270                     lp.ptr.unwritten            != rp.ptr.unwritten ||
 271                     lp.has_ec                   != rp.has_ec)
 272                         return false;
 273
 274                 /* Extents may not straddle buckets: */
 275                 ca = bch_dev_bkey_exists(c, lp.ptr.dev);
 276                 if (PTR_BUCKET_NR(ca, &lp.ptr) != PTR_BUCKET_NR(ca, &rp.ptr))
 277                         return false;
 278
 279                 if (lp.has_ec                   != rp.has_ec ||
 280                     (lp.has_ec &&
 281                      (lp.ec.block               != rp.ec.block ||
 282                       lp.ec.redundancy          != rp.ec.redundancy ||
 283                       lp.ec.idx                 != rp.ec.idx)))
 284                         return false;
 285
 286                 if (lp.crc.compression_type     != rp.crc.compression_type ||
 287                     lp.crc.nonce                != rp.crc.nonce)
 288                         return false;
 289
 290                 if (lp.crc.offset + lp.crc.live_size + rp.crc.live_size <=
 291                     lp.crc.uncompressed_size) {
 292                         /* can use left extent's crc entry */
 293                 } else if (lp.crc.live_size <= rp.crc.offset) {
 294                         /* can use right extent's crc entry */
 295                 } else {
 296                         /* check if checksums can be merged: */
 297                         if (lp.crc.csum_type            != rp.crc.csum_type ||
 298                             lp.crc.nonce                != rp.crc.nonce ||
 299                             crc_is_compressed(lp.crc) ||
 300                             !bch2_checksum_mergeable(lp.crc.csum_type))
 301                                 return false;
 302
 303                         if (lp.crc.offset + lp.crc.live_size != lp.crc.compressed_size ||
 304                             rp.crc.offset)
 305                                 return false;
 306
 307                         if (lp.crc.csum_type &&
 308                             lp.crc.uncompressed_size +
 309                             rp.crc.uncompressed_size > (c->opts.encoded_extent_max >> 9))
 310                                 return false;
 311                 }
 312
 313                 en_l = extent_entry_next(en_l);
 314                 en_r = extent_entry_next(en_r);
 315         }
 316
 317         en_l = l_ptrs.start;
 318         en_r = r_ptrs.start;
 319         while (en_l < l_ptrs.end && en_r < r_ptrs.end) {
 320                 if (extent_entry_is_crc(en_l)) {
 321                         struct bch_extent_crc_unpacked crc_l = bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
 322                         struct bch_extent_crc_unpacked crc_r = bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
 323
 324                         if (crc_l.uncompressed_size + crc_r.uncompressed_size >
 325                             bch2_crc_field_size_max[extent_entry_type(en_l)])
 326                                 return false;
 327                 }
 328
 329                 en_l = extent_entry_next(en_l);
 330                 en_r = extent_entry_next(en_r);
 331         }
 332
 333         use_right_ptr = false;
 334         en_l = l_ptrs.start;
 335         en_r = r_ptrs.start;
 336         while (en_l < l_ptrs.end) {
 337                 if (extent_entry_type(en_l) == BCH_EXTENT_ENTRY_ptr &&
 338                     use_right_ptr)
 339                         en_l->ptr = en_r->ptr;
 340
 341                 if (extent_entry_is_crc(en_l)) {
 342                         struct bch_extent_crc_unpacked crc_l =
 343                                 bch2_extent_crc_unpack(l.k, entry_to_crc(en_l));
 344                         struct bch_extent_crc_unpacked crc_r =
 345                                 bch2_extent_crc_unpack(r.k, entry_to_crc(en_r));
 346
 347                         use_right_ptr = false;
 348
 349                         if (crc_l.offset + crc_l.live_size + crc_r.live_size <=
 350                             crc_l.uncompressed_size) {
 351                                 /* can use left extent's crc entry */
 352                         } else if (crc_l.live_size <= crc_r.offset) {
 353                                 /* can use right extent's crc entry */
 354                                 crc_r.offset -= crc_l.live_size;
 355                                 bch2_extent_crc_pack(entry_to_crc(en_l), crc_r,
 356                                                      extent_entry_type(en_l));
 357                                 use_right_ptr = true;
 358                         } else {
 359                                 crc_l.csum = bch2_checksum_merge(crc_l.csum_type,
 360                                                                  crc_l.csum,
 361                                                                  crc_r.csum,
 362                                                                  crc_r.uncompressed_size << 9);
 363
 364                                 crc_l.uncompressed_size += crc_r.uncompressed_size;
 365                                 crc_l.compressed_size   += crc_r.compressed_size;
 366                                 bch2_extent_crc_pack(entry_to_crc(en_l), crc_l,
 367                                                      extent_entry_type(en_l));
 368                         }
 369                 }
 370
 371                 en_l = extent_entry_next(en_l);
 372                 en_r = extent_entry_next(en_r);
 373         }
 374
 375         bch2_key_resize(l.k, l.k->size + r.k->size);
 376         return true;
 377 }
 378
 379 /* KEY_TYPE_reservation: */
 380
 381 int bch2_reservation_invalid(struct bch_fs *c, struct bkey_s_c k,
 382                              enum bkey_invalid_flags flags,
 383                              struct printbuf *err)
 384 {
 385         struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
 386         int ret = 0;
 387
 388         bkey_fsck_err_on(!r.v->nr_replicas || r.v->nr_replicas > BCH_REPLICAS_MAX, c, err,
 389                          reservation_key_nr_replicas_invalid,
 390                          "invalid nr_replicas (%u)", r.v->nr_replicas);
 391 fsck_err:
 392         return ret;
 393 }
 394
 395 void bch2_reservation_to_text(struct printbuf *out, struct bch_fs *c,
 396                               struct bkey_s_c k)
 397 {
 398         struct bkey_s_c_reservation r = bkey_s_c_to_reservation(k);
 399
 400         prt_printf(out, "generation %u replicas %u",
 401                le32_to_cpu(r.v->generation),
 402                r.v->nr_replicas);
 403 }
 404
 405 bool bch2_reservation_merge(struct bch_fs *c, struct bkey_s _l, struct bkey_s_c _r)
 406 {
 407         struct bkey_s_reservation l = bkey_s_to_reservation(_l);
 408         struct bkey_s_c_reservation r = bkey_s_c_to_reservation(_r);
 409
 410         if (l.v->generation != r.v->generation ||
 411             l.v->nr_replicas != r.v->nr_replicas)
 412                 return false;
 413
 414         bch2_key_resize(l.k, l.k->size + r.k->size);
 415         return true;
 416 }
 417
 418 /* Extent checksum entries: */
 419
 420 /* returns true if not equal */
 421 static inline bool bch2_crc_unpacked_cmp(struct bch_extent_crc_unpacked l,
 422                                          struct bch_extent_crc_unpacked r)
 423 {
 424         return (l.csum_type             != r.csum_type ||
 425                 l.compression_type      != r.compression_type ||
 426                 l.compressed_size       != r.compressed_size ||
 427                 l.uncompressed_size     != r.uncompressed_size ||
 428                 l.offset                != r.offset ||
 429                 l.live_size             != r.live_size ||
 430                 l.nonce                 != r.nonce ||
 431                 bch2_crc_cmp(l.csum, r.csum));
 432 }
 433
 434 static inline bool can_narrow_crc(struct bch_extent_crc_unpacked u,
 435                                   struct bch_extent_crc_unpacked n)
 436 {
 437         return !crc_is_compressed(u) &&
 438                 u.csum_type &&
 439                 u.uncompressed_size > u.live_size &&
 440                 bch2_csum_type_is_encryption(u.csum_type) ==
 441                 bch2_csum_type_is_encryption(n.csum_type);
 442 }
 443
 444 bool bch2_can_narrow_extent_crcs(struct bkey_s_c k,
 445                                  struct bch_extent_crc_unpacked n)
 446 {
 447         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 448         struct bch_extent_crc_unpacked crc;
 449         const union bch_extent_entry *i;
 450
 451         if (!n.csum_type)
 452                 return false;
 453
 454         bkey_for_each_crc(k.k, ptrs, crc, i)
 455                 if (can_narrow_crc(crc, n))
 456                         return true;
 457
 458         return false;
 459 }
 460
 461 /*
 462  * We're writing another replica for this extent, so while we've got the data in
 463  * memory we'll be computing a new checksum for the currently live data.
 464  *
 465  * If there are other replicas we aren't moving, and they are checksummed but
 466  * not compressed, we can modify them to point to only the data that is
 467  * currently live (so that readers won't have to bounce) while we've got the
 468  * checksum we need:
 469  */
 470 bool bch2_bkey_narrow_crcs(struct bkey_i *k, struct bch_extent_crc_unpacked n)
 471 {
 472         struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 473         struct bch_extent_crc_unpacked u;
 474         struct extent_ptr_decoded p;
 475         union bch_extent_entry *i;
 476         bool ret = false;
 477
 478         /* Find a checksum entry that covers only live data: */
 479         if (!n.csum_type) {
 480                 bkey_for_each_crc(&k->k, ptrs, u, i)
 481                         if (!crc_is_compressed(u) &&
 482                             u.csum_type &&
 483                             u.live_size == u.uncompressed_size) {
 484                                 n = u;
 485                                 goto found;
 486                         }
 487                 return false;
 488         }
 489 found:
 490         BUG_ON(crc_is_compressed(n));
 491         BUG_ON(n.offset);
 492         BUG_ON(n.live_size != k->k.size);
 493
 494 restart_narrow_pointers:
 495         ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 496
 497         bkey_for_each_ptr_decode(&k->k, ptrs, p, i)
 498                 if (can_narrow_crc(p.crc, n)) {
 499                         bch2_bkey_drop_ptr_noerror(bkey_i_to_s(k), &i->ptr);
 500                         p.ptr.offset += p.crc.offset;
 501                         p.crc = n;
 502                         bch2_extent_ptr_decoded_append(k, &p);
 503                         ret = true;
 504                         goto restart_narrow_pointers;
 505                 }
 506
 507         return ret;
 508 }
 509
 510 static void bch2_extent_crc_pack(union bch_extent_crc *dst,
 511                                  struct bch_extent_crc_unpacked src,
 512                                  enum bch_extent_entry_type type)
 513 {
 514 #define set_common_fields(_dst, _src)                                   \
 515                 _dst.type               = 1 << type;                    \
 516                 _dst.csum_type          = _src.csum_type,               \
 517                 _dst.compression_type   = _src.compression_type,        \
 518                 _dst._compressed_size   = _src.compressed_size - 1,     \
 519                 _dst._uncompressed_size = _src.uncompressed_size - 1,   \
 520                 _dst.offset             = _src.offset
 521
 522         switch (type) {
 523         case BCH_EXTENT_ENTRY_crc32:
 524                 set_common_fields(dst->crc32, src);
 525                 dst->crc32.csum         = (u32 __force) *((__le32 *) &src.csum.lo);
 526                 break;
 527         case BCH_EXTENT_ENTRY_crc64:
 528                 set_common_fields(dst->crc64, src);
 529                 dst->crc64.nonce        = src.nonce;
 530                 dst->crc64.csum_lo      = (u64 __force) src.csum.lo;
 531                 dst->crc64.csum_hi      = (u64 __force) *((__le16 *) &src.csum.hi);
 532                 break;
 533         case BCH_EXTENT_ENTRY_crc128:
 534                 set_common_fields(dst->crc128, src);
 535                 dst->crc128.nonce       = src.nonce;
 536                 dst->crc128.csum        = src.csum;
 537                 break;
 538         default:
 539                 BUG();
 540         }
 541 #undef set_common_fields
 542 }
 543
 544 void bch2_extent_crc_append(struct bkey_i *k,
 545                             struct bch_extent_crc_unpacked new)
 546 {
 547         struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 548         union bch_extent_crc *crc = (void *) ptrs.end;
 549         enum bch_extent_entry_type type;
 550
 551         if (bch_crc_bytes[new.csum_type]        <= 4 &&
 552             new.uncompressed_size               <= CRC32_SIZE_MAX &&
 553             new.nonce                           <= CRC32_NONCE_MAX)
 554                 type = BCH_EXTENT_ENTRY_crc32;
 555         else if (bch_crc_bytes[new.csum_type]   <= 10 &&
 556                    new.uncompressed_size        <= CRC64_SIZE_MAX &&
 557                    new.nonce                    <= CRC64_NONCE_MAX)
 558                 type = BCH_EXTENT_ENTRY_crc64;
 559         else if (bch_crc_bytes[new.csum_type]   <= 16 &&
 560                    new.uncompressed_size        <= CRC128_SIZE_MAX &&
 561                    new.nonce                    <= CRC128_NONCE_MAX)
 562                 type = BCH_EXTENT_ENTRY_crc128;
 563         else
 564                 BUG();
 565
 566         bch2_extent_crc_pack(crc, new, type);
 567
 568         k->k.u64s += extent_entry_u64s(ptrs.end);
 569
 570         EBUG_ON(bkey_val_u64s(&k->k) > BKEY_EXTENT_VAL_U64s_MAX);
 571 }
 572
 573 /* Generic code for keys with pointers: */
 574
 575 unsigned bch2_bkey_nr_ptrs(struct bkey_s_c k)
 576 {
 577         return bch2_bkey_devs(k).nr;
 578 }
 579
 580 unsigned bch2_bkey_nr_ptrs_allocated(struct bkey_s_c k)
 581 {
 582         return k.k->type == KEY_TYPE_reservation
 583                 ? bkey_s_c_to_reservation(k).v->nr_replicas
 584                 : bch2_bkey_dirty_devs(k).nr;
 585 }
 586
 587 unsigned bch2_bkey_nr_ptrs_fully_allocated(struct bkey_s_c k)
 588 {
 589         unsigned ret = 0;
 590
 591         if (k.k->type == KEY_TYPE_reservation) {
 592                 ret = bkey_s_c_to_reservation(k).v->nr_replicas;
 593         } else {
 594                 struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 595                 const union bch_extent_entry *entry;
 596                 struct extent_ptr_decoded p;
 597
 598                 bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 599                         ret += !p.ptr.cached && !crc_is_compressed(p.crc);
 600         }
 601
 602         return ret;
 603 }
 604
 605 unsigned bch2_bkey_sectors_compressed(struct bkey_s_c k)
 606 {
 607         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 608         const union bch_extent_entry *entry;
 609         struct extent_ptr_decoded p;
 610         unsigned ret = 0;
 611
 612         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 613                 if (!p.ptr.cached && crc_is_compressed(p.crc))
 614                         ret += p.crc.compressed_size;
 615
 616         return ret;
 617 }
 618
 619 bool bch2_bkey_is_incompressible(struct bkey_s_c k)
 620 {
 621         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 622         const union bch_extent_entry *entry;
 623         struct bch_extent_crc_unpacked crc;
 624
 625         bkey_for_each_crc(k.k, ptrs, crc, entry)
 626                 if (crc.compression_type == BCH_COMPRESSION_TYPE_incompressible)
 627                         return true;
 628         return false;
 629 }
 630
 631 unsigned bch2_bkey_replicas(struct bch_fs *c, struct bkey_s_c k)
 632 {
 633         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 634         const union bch_extent_entry *entry;
 635         struct extent_ptr_decoded p = { 0 };
 636         unsigned replicas = 0;
 637
 638         bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
 639                 if (p.ptr.cached)
 640                         continue;
 641
 642                 if (p.has_ec)
 643                         replicas += p.ec.redundancy;
 644
 645                 replicas++;
 646
 647         }
 648
 649         return replicas;
 650 }
 651
 652 static inline unsigned __extent_ptr_durability(struct bch_dev *ca, struct extent_ptr_decoded *p)
 653 {
 654         if (p->ptr.cached)
 655                 return 0;
 656
 657         return p->has_ec
 658                 ? p->ec.redundancy + 1
 659                 : ca->mi.durability;
 660 }
 661
 662 unsigned bch2_extent_ptr_desired_durability(struct bch_fs *c, struct extent_ptr_decoded *p)
 663 {
 664         struct bch_dev *ca = bch_dev_bkey_exists(c, p->ptr.dev);
 665
 666         return __extent_ptr_durability(ca, p);
 667 }
 668
 669 unsigned bch2_extent_ptr_durability(struct bch_fs *c, struct extent_ptr_decoded *p)
 670 {
 671         struct bch_dev *ca = bch_dev_bkey_exists(c, p->ptr.dev);
 672
 673         if (ca->mi.state == BCH_MEMBER_STATE_failed)
 674                 return 0;
 675
 676         return __extent_ptr_durability(ca, p);
 677 }
 678
 679 unsigned bch2_bkey_durability(struct bch_fs *c, struct bkey_s_c k)
 680 {
 681         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 682         const union bch_extent_entry *entry;
 683         struct extent_ptr_decoded p;
 684         unsigned durability = 0;
 685
 686         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 687                 durability += bch2_extent_ptr_durability(c, &p);
 688
 689         return durability;
 690 }
 691
 692 static unsigned bch2_bkey_durability_safe(struct bch_fs *c, struct bkey_s_c k)
 693 {
 694         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 695         const union bch_extent_entry *entry;
 696         struct extent_ptr_decoded p;
 697         unsigned durability = 0;
 698
 699         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 700                 if (p.ptr.dev < c->sb.nr_devices && c->devs[p.ptr.dev])
 701                         durability += bch2_extent_ptr_durability(c, &p);
 702
 703         return durability;
 704 }
 705
 706 void bch2_bkey_extent_entry_drop(struct bkey_i *k, union bch_extent_entry *entry)
 707 {
 708         union bch_extent_entry *end = bkey_val_end(bkey_i_to_s(k));
 709         union bch_extent_entry *next = extent_entry_next(entry);
 710
 711         memmove_u64s(entry, next, (u64 *) end - (u64 *) next);
 712         k->k.u64s -= extent_entry_u64s(entry);
 713 }
 714
 715 void bch2_extent_ptr_decoded_append(struct bkey_i *k,
 716                                     struct extent_ptr_decoded *p)
 717 {
 718         struct bkey_ptrs ptrs = bch2_bkey_ptrs(bkey_i_to_s(k));
 719         struct bch_extent_crc_unpacked crc =
 720                 bch2_extent_crc_unpack(&k->k, NULL);
 721         union bch_extent_entry *pos;
 722
 723         if (!bch2_crc_unpacked_cmp(crc, p->crc)) {
 724                 pos = ptrs.start;
 725                 goto found;
 726         }
 727
 728         bkey_for_each_crc(&k->k, ptrs, crc, pos)
 729                 if (!bch2_crc_unpacked_cmp(crc, p->crc)) {
 730                         pos = extent_entry_next(pos);
 731                         goto found;
 732                 }
 733
 734         bch2_extent_crc_append(k, p->crc);
 735         pos = bkey_val_end(bkey_i_to_s(k));
 736 found:
 737         p->ptr.type = 1 << BCH_EXTENT_ENTRY_ptr;
 738         __extent_entry_insert(k, pos, to_entry(&p->ptr));
 739
 740         if (p->has_ec) {
 741                 p->ec.type = 1 << BCH_EXTENT_ENTRY_stripe_ptr;
 742                 __extent_entry_insert(k, pos, to_entry(&p->ec));
 743         }
 744 }
 745
 746 static union bch_extent_entry *extent_entry_prev(struct bkey_ptrs ptrs,
 747                                           union bch_extent_entry *entry)
 748 {
 749         union bch_extent_entry *i = ptrs.start;
 750
 751         if (i == entry)
 752                 return NULL;
 753
 754         while (extent_entry_next(i) != entry)
 755                 i = extent_entry_next(i);
 756         return i;
 757 }
 758
 759 /*
 760  * Returns pointer to the next entry after the one being dropped:
 761  */
 762 union bch_extent_entry *bch2_bkey_drop_ptr_noerror(struct bkey_s k,
 763                                                    struct bch_extent_ptr *ptr)
 764 {
 765         struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
 766         union bch_extent_entry *entry = to_entry(ptr), *next;
 767         union bch_extent_entry *ret = entry;
 768         bool drop_crc = true;
 769
 770         EBUG_ON(ptr < &ptrs.start->ptr ||
 771                 ptr >= &ptrs.end->ptr);
 772         EBUG_ON(ptr->type != 1 << BCH_EXTENT_ENTRY_ptr);
 773
 774         for (next = extent_entry_next(entry);
 775              next != ptrs.end;
 776              next = extent_entry_next(next)) {
 777                 if (extent_entry_is_crc(next)) {
 778                         break;
 779                 } else if (extent_entry_is_ptr(next)) {
 780                         drop_crc = false;
 781                         break;
 782                 }
 783         }
 784
 785         extent_entry_drop(k, entry);
 786
 787         while ((entry = extent_entry_prev(ptrs, entry))) {
 788                 if (extent_entry_is_ptr(entry))
 789                         break;
 790
 791                 if ((extent_entry_is_crc(entry) && drop_crc) ||
 792                     extent_entry_is_stripe_ptr(entry)) {
 793                         ret = (void *) ret - extent_entry_bytes(entry);
 794                         extent_entry_drop(k, entry);
 795                 }
 796         }
 797
 798         return ret;
 799 }
 800
 801 union bch_extent_entry *bch2_bkey_drop_ptr(struct bkey_s k,
 802                                            struct bch_extent_ptr *ptr)
 803 {
 804         bool have_dirty = bch2_bkey_dirty_devs(k.s_c).nr;
 805         union bch_extent_entry *ret =
 806                 bch2_bkey_drop_ptr_noerror(k, ptr);
 807
 808         /*
 809          * If we deleted all the dirty pointers and there's still cached
 810          * pointers, we could set the cached pointers to dirty if they're not
 811          * stale - but to do that correctly we'd need to grab an open_bucket
 812          * reference so that we don't race with bucket reuse:
 813          */
 814         if (have_dirty &&
 815             !bch2_bkey_dirty_devs(k.s_c).nr) {
 816                 k.k->type = KEY_TYPE_error;
 817                 set_bkey_val_u64s(k.k, 0);
 818                 ret = NULL;
 819         } else if (!bch2_bkey_nr_ptrs(k.s_c)) {
 820                 k.k->type = KEY_TYPE_deleted;
 821                 set_bkey_val_u64s(k.k, 0);
 822                 ret = NULL;
 823         }
 824
 825         return ret;
 826 }
 827
 828 void bch2_bkey_drop_device(struct bkey_s k, unsigned dev)
 829 {
 830         struct bch_extent_ptr *ptr;
 831
 832         bch2_bkey_drop_ptrs(k, ptr, ptr->dev == dev);
 833 }
 834
 835 void bch2_bkey_drop_device_noerror(struct bkey_s k, unsigned dev)
 836 {
 837         struct bch_extent_ptr *ptr = bch2_bkey_has_device(k, dev);
 838
 839         if (ptr)
 840                 bch2_bkey_drop_ptr_noerror(k, ptr);
 841 }
 842
 843 const struct bch_extent_ptr *bch2_bkey_has_device_c(struct bkey_s_c k, unsigned dev)
 844 {
 845         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 846         const struct bch_extent_ptr *ptr;
 847
 848         bkey_for_each_ptr(ptrs, ptr)
 849                 if (ptr->dev == dev)
 850                         return ptr;
 851
 852         return NULL;
 853 }
 854
 855 bool bch2_bkey_has_target(struct bch_fs *c, struct bkey_s_c k, unsigned target)
 856 {
 857         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 858         const struct bch_extent_ptr *ptr;
 859
 860         bkey_for_each_ptr(ptrs, ptr)
 861                 if (bch2_dev_in_target(c, ptr->dev, target) &&
 862                     (!ptr->cached ||
 863                      !ptr_stale(bch_dev_bkey_exists(c, ptr->dev), ptr)))
 864                         return true;
 865
 866         return false;
 867 }
 868
 869 bool bch2_bkey_matches_ptr(struct bch_fs *c, struct bkey_s_c k,
 870                            struct bch_extent_ptr m, u64 offset)
 871 {
 872         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 873         const union bch_extent_entry *entry;
 874         struct extent_ptr_decoded p;
 875
 876         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 877                 if (p.ptr.dev   == m.dev &&
 878                     p.ptr.gen   == m.gen &&
 879                     (s64) p.ptr.offset + p.crc.offset - bkey_start_offset(k.k) ==
 880                     (s64) m.offset  - offset)
 881                         return true;
 882
 883         return false;
 884 }
 885
 886 /*
 887  * Returns true if two extents refer to the same data:
 888  */
 889 bool bch2_extents_match(struct bkey_s_c k1, struct bkey_s_c k2)
 890 {
 891         if (k1.k->type != k2.k->type)
 892                 return false;
 893
 894         if (bkey_extent_is_direct_data(k1.k)) {
 895                 struct bkey_ptrs_c ptrs1 = bch2_bkey_ptrs_c(k1);
 896                 struct bkey_ptrs_c ptrs2 = bch2_bkey_ptrs_c(k2);
 897                 const union bch_extent_entry *entry1, *entry2;
 898                 struct extent_ptr_decoded p1, p2;
 899
 900                 if (bkey_extent_is_unwritten(k1) != bkey_extent_is_unwritten(k2))
 901                         return false;
 902
 903                 bkey_for_each_ptr_decode(k1.k, ptrs1, p1, entry1)
 904                         bkey_for_each_ptr_decode(k2.k, ptrs2, p2, entry2)
 905                                 if (p1.ptr.dev          == p2.ptr.dev &&
 906                                     p1.ptr.gen          == p2.ptr.gen &&
 907                                     (s64) p1.ptr.offset + p1.crc.offset - bkey_start_offset(k1.k) ==
 908                                     (s64) p2.ptr.offset + p2.crc.offset - bkey_start_offset(k2.k))
 909                                         return true;
 910
 911                 return false;
 912         } else {
 913                 /* KEY_TYPE_deleted, etc. */
 914                 return true;
 915         }
 916 }
 917
 918 struct bch_extent_ptr *
 919 bch2_extent_has_ptr(struct bkey_s_c k1, struct extent_ptr_decoded p1, struct bkey_s k2)
 920 {
 921         struct bkey_ptrs ptrs2 = bch2_bkey_ptrs(k2);
 922         union bch_extent_entry *entry2;
 923         struct extent_ptr_decoded p2;
 924
 925         bkey_for_each_ptr_decode(k2.k, ptrs2, p2, entry2)
 926                 if (p1.ptr.dev          == p2.ptr.dev &&
 927                     p1.ptr.gen          == p2.ptr.gen &&
 928                     (s64) p1.ptr.offset + p1.crc.offset - bkey_start_offset(k1.k) ==
 929                     (s64) p2.ptr.offset + p2.crc.offset - bkey_start_offset(k2.k))
 930                         return &entry2->ptr;
 931
 932         return NULL;
 933 }
 934
 935 void bch2_extent_ptr_set_cached(struct bkey_s k, struct bch_extent_ptr *ptr)
 936 {
 937         struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
 938         union bch_extent_entry *entry;
 939         union bch_extent_entry *ec = NULL;
 940
 941         bkey_extent_entry_for_each(ptrs, entry) {
 942                 if (&entry->ptr == ptr) {
 943                         ptr->cached = true;
 944                         if (ec)
 945                                 extent_entry_drop(k, ec);
 946                         return;
 947                 }
 948
 949                 if (extent_entry_is_stripe_ptr(entry))
 950                         ec = entry;
 951                 else if (extent_entry_is_ptr(entry))
 952                         ec = NULL;
 953         }
 954
 955         BUG();
 956 }
 957
 958 /*
 959  * bch_extent_normalize - clean up an extent, dropping stale pointers etc.
 960  *
 961  * Returns true if @k should be dropped entirely
 962  *
 963  * For existing keys, only called when btree nodes are being rewritten, not when
 964  * they're merely being compacted/resorted in memory.
 965  */
 966 bool bch2_extent_normalize(struct bch_fs *c, struct bkey_s k)
 967 {
 968         struct bch_extent_ptr *ptr;
 969
 970         bch2_bkey_drop_ptrs(k, ptr,
 971                 ptr->cached &&
 972                 ptr_stale(bch_dev_bkey_exists(c, ptr->dev), ptr));
 973
 974         return bkey_deleted(k.k);
 975 }
 976
 977 void bch2_bkey_ptrs_to_text(struct printbuf *out, struct bch_fs *c,
 978                             struct bkey_s_c k)
 979 {
 980         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 981         const union bch_extent_entry *entry;
 982         bool first = true;
 983
 984         if (c)
 985                 prt_printf(out, "durability: %u ", bch2_bkey_durability_safe(c, k));
 986
 987         bkey_extent_entry_for_each(ptrs, entry) {
 988                 if (!first)
 989                         prt_printf(out, " ");
 990
 991                 switch (__extent_entry_type(entry)) {
 992                 case BCH_EXTENT_ENTRY_ptr: {
 993                         const struct bch_extent_ptr *ptr = entry_to_ptr(entry);
 994                         struct bch_dev *ca = c && ptr->dev < c->sb.nr_devices && c->devs[ptr->dev]
 995                                 ? bch_dev_bkey_exists(c, ptr->dev)
 996                                 : NULL;
 997
 998                         if (!ca) {
 999                                 prt_printf(out, "ptr: %u:%llu gen %u%s", ptr->dev,
1000                                        (u64) ptr->offset, ptr->gen,
1001                                        ptr->cached ? " cached" : "");
1002                         } else {
1003                                 u32 offset;
1004                                 u64 b = sector_to_bucket_and_offset(ca, ptr->offset, &offset);
1005
1006                                 prt_printf(out, "ptr: %u:%llu:%u gen %u",
1007                                            ptr->dev, b, offset, ptr->gen);
1008                                 if (ptr->cached)
1009                                         prt_str(out, " cached");
1010                                 if (ptr->unwritten)
1011                                         prt_str(out, " unwritten");
1012                                 if (ca && ptr_stale(ca, ptr))
1013                                         prt_printf(out, " stale");
1014                         }
1015                         break;
1016                 }
1017                 case BCH_EXTENT_ENTRY_crc32:
1018                 case BCH_EXTENT_ENTRY_crc64:
1019                 case BCH_EXTENT_ENTRY_crc128: {
1020                         struct bch_extent_crc_unpacked crc =
1021                                 bch2_extent_crc_unpack(k.k, entry_to_crc(entry));
1022
1023                         prt_printf(out, "crc: c_size %u size %u offset %u nonce %u csum %s compress %s",
1024                                crc.compressed_size,
1025                                crc.uncompressed_size,
1026                                crc.offset, crc.nonce,
1027                                bch2_csum_types[crc.csum_type],
1028                                bch2_compression_types[crc.compression_type]);
1029                         break;
1030                 }
1031                 case BCH_EXTENT_ENTRY_stripe_ptr: {
1032                         const struct bch_extent_stripe_ptr *ec = &entry->stripe_ptr;
1033
1034                         prt_printf(out, "ec: idx %llu block %u",
1035                                (u64) ec->idx, ec->block);
1036                         break;
1037                 }
1038                 case BCH_EXTENT_ENTRY_rebalance: {
1039                         const struct bch_extent_rebalance *r = &entry->rebalance;
1040
1041                         prt_str(out, "rebalance: target ");
1042                         if (c)
1043                                 bch2_target_to_text(out, c, r->target);
1044                         else
1045                                 prt_printf(out, "%u", r->target);
1046                         prt_str(out, " compression ");
1047                         bch2_compression_opt_to_text(out, r->compression);
1048                         break;
1049                 }
1050                 default:
1051                         prt_printf(out, "(invalid extent entry %.16llx)", *((u64 *) entry));
1052                         return;
1053                 }
1054
1055                 first = false;
1056         }
1057 }
1058
1059 static int extent_ptr_invalid(struct bch_fs *c,
1060                               struct bkey_s_c k,
1061                               enum bkey_invalid_flags flags,
1062                               const struct bch_extent_ptr *ptr,
1063                               unsigned size_ondisk,
1064                               bool metadata,
1065                               struct printbuf *err)
1066 {
1067         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1068         const struct bch_extent_ptr *ptr2;
1069         u64 bucket;
1070         u32 bucket_offset;
1071         struct bch_dev *ca;
1072         int ret = 0;
1073
1074         if (!bch2_dev_exists2(c, ptr->dev)) {
1075                 /*
1076                  * If we're in the write path this key might have already been
1077                  * overwritten, and we could be seeing a device that doesn't
1078                  * exist anymore due to racing with device removal:
1079                  */
1080                 if (flags & BKEY_INVALID_WRITE)
1081                         return 0;
1082
1083                 bkey_fsck_err(c, err, ptr_to_invalid_device,
1084                            "pointer to invalid device (%u)", ptr->dev);
1085         }
1086
1087         ca = bch_dev_bkey_exists(c, ptr->dev);
1088         bkey_for_each_ptr(ptrs, ptr2)
1089                 bkey_fsck_err_on(ptr != ptr2 && ptr->dev == ptr2->dev, c, err,
1090                                  ptr_to_duplicate_device,
1091                                  "multiple pointers to same device (%u)", ptr->dev);
1092
1093         bucket = sector_to_bucket_and_offset(ca, ptr->offset, &bucket_offset);
1094
1095         bkey_fsck_err_on(bucket >= ca->mi.nbuckets, c, err,
1096                          ptr_after_last_bucket,
1097                          "pointer past last bucket (%llu > %llu)", bucket, ca->mi.nbuckets);
1098         bkey_fsck_err_on(ptr->offset < bucket_to_sector(ca, ca->mi.first_bucket), c, err,
1099                          ptr_before_first_bucket,
1100                          "pointer before first bucket (%llu < %u)", bucket, ca->mi.first_bucket);
1101         bkey_fsck_err_on(bucket_offset + size_ondisk > ca->mi.bucket_size, c, err,
1102                          ptr_spans_multiple_buckets,
1103                          "pointer spans multiple buckets (%u + %u > %u)",
1104                        bucket_offset, size_ondisk, ca->mi.bucket_size);
1105 fsck_err:
1106         return ret;
1107 }
1108
1109 int bch2_bkey_ptrs_invalid(struct bch_fs *c, struct bkey_s_c k,
1110                            enum bkey_invalid_flags flags,
1111                            struct printbuf *err)
1112 {
1113         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1114         const union bch_extent_entry *entry;
1115         struct bch_extent_crc_unpacked crc;
1116         unsigned size_ondisk = k.k->size;
1117         unsigned nonce = UINT_MAX;
1118         unsigned nr_ptrs = 0;
1119         bool have_written = false, have_unwritten = false, have_ec = false, crc_since_last_ptr = false;
1120         int ret = 0;
1121
1122         if (bkey_is_btree_ptr(k.k))
1123                 size_ondisk = btree_sectors(c);
1124
1125         bkey_extent_entry_for_each(ptrs, entry) {
1126                 bkey_fsck_err_on(__extent_entry_type(entry) >= BCH_EXTENT_ENTRY_MAX, c, err,
1127                         extent_ptrs_invalid_entry,
1128                         "invalid extent entry type (got %u, max %u)",
1129                         __extent_entry_type(entry), BCH_EXTENT_ENTRY_MAX);
1130
1131                 bkey_fsck_err_on(bkey_is_btree_ptr(k.k) &&
1132                                  !extent_entry_is_ptr(entry), c, err,
1133                                  btree_ptr_has_non_ptr,
1134                                  "has non ptr field");
1135
1136                 switch (extent_entry_type(entry)) {
1137                 case BCH_EXTENT_ENTRY_ptr:
1138                         ret = extent_ptr_invalid(c, k, flags, &entry->ptr,
1139                                                  size_ondisk, false, err);
1140                         if (ret)
1141                                 return ret;
1142
1143                         bkey_fsck_err_on(entry->ptr.cached && have_ec, c, err,
1144                                          ptr_cached_and_erasure_coded,
1145                                          "cached, erasure coded ptr");
1146
1147                         if (!entry->ptr.unwritten)
1148                                 have_written = true;
1149                         else
1150                                 have_unwritten = true;
1151
1152                         have_ec = false;
1153                         crc_since_last_ptr = false;
1154                         nr_ptrs++;
1155                         break;
1156                 case BCH_EXTENT_ENTRY_crc32:
1157                 case BCH_EXTENT_ENTRY_crc64:
1158                 case BCH_EXTENT_ENTRY_crc128:
1159                         crc = bch2_extent_crc_unpack(k.k, entry_to_crc(entry));
1160
1161                         bkey_fsck_err_on(crc.offset + crc.live_size > crc.uncompressed_size, c, err,
1162                                          ptr_crc_uncompressed_size_too_small,
1163                                          "checksum offset + key size > uncompressed size");
1164                         bkey_fsck_err_on(!bch2_checksum_type_valid(c, crc.csum_type), c, err,
1165                                          ptr_crc_csum_type_unknown,
1166                                          "invalid checksum type");
1167                         bkey_fsck_err_on(crc.compression_type >= BCH_COMPRESSION_TYPE_NR, c, err,
1168                                          ptr_crc_compression_type_unknown,
1169                                          "invalid compression type");
1170
1171                         if (bch2_csum_type_is_encryption(crc.csum_type)) {
1172                                 if (nonce == UINT_MAX)
1173                                         nonce = crc.offset + crc.nonce;
1174                                 else if (nonce != crc.offset + crc.nonce)
1175                                         bkey_fsck_err(c, err, ptr_crc_nonce_mismatch,
1176                                                       "incorrect nonce");
1177                         }
1178
1179                         bkey_fsck_err_on(crc_since_last_ptr, c, err,
1180                                          ptr_crc_redundant,
1181                                          "redundant crc entry");
1182                         crc_since_last_ptr = true;
1183
1184                         bkey_fsck_err_on(crc_is_encoded(crc) &&
1185                                          (crc.uncompressed_size > c->opts.encoded_extent_max >> 9) &&
1186                                          (flags & (BKEY_INVALID_WRITE|BKEY_INVALID_COMMIT)), c, err,
1187                                          ptr_crc_uncompressed_size_too_big,
1188                                          "too large encoded extent");
1189
1190                         size_ondisk = crc.compressed_size;
1191                         break;
1192                 case BCH_EXTENT_ENTRY_stripe_ptr:
1193                         bkey_fsck_err_on(have_ec, c, err,
1194                                          ptr_stripe_redundant,
1195                                          "redundant stripe entry");
1196                         have_ec = true;
1197                         break;
1198                 case BCH_EXTENT_ENTRY_rebalance: {
1199                         const struct bch_extent_rebalance *r = &entry->rebalance;
1200
1201                         if (!bch2_compression_opt_valid(r->compression)) {
1202                                 struct bch_compression_opt opt = __bch2_compression_decode(r->compression);
1203                                 prt_printf(err, "invalid compression opt %u:%u",
1204                                            opt.type, opt.level);
1205                                 return -BCH_ERR_invalid_bkey;
1206                         }
1207                         break;
1208                 }
1209                 }
1210         }
1211
1212         bkey_fsck_err_on(!nr_ptrs, c, err,
1213                          extent_ptrs_no_ptrs,
1214                          "no ptrs");
1215         bkey_fsck_err_on(nr_ptrs > BCH_BKEY_PTRS_MAX, c, err,
1216                          extent_ptrs_too_many_ptrs,
1217                          "too many ptrs: %u > %u", nr_ptrs, BCH_BKEY_PTRS_MAX);
1218         bkey_fsck_err_on(have_written && have_unwritten, c, err,
1219                          extent_ptrs_written_and_unwritten,
1220                          "extent with unwritten and written ptrs");
1221         bkey_fsck_err_on(k.k->type != KEY_TYPE_extent && have_unwritten, c, err,
1222                          extent_ptrs_unwritten,
1223                          "has unwritten ptrs");
1224         bkey_fsck_err_on(crc_since_last_ptr, c, err,
1225                          extent_ptrs_redundant_crc,
1226                          "redundant crc entry");
1227         bkey_fsck_err_on(have_ec, c, err,
1228                          extent_ptrs_redundant_stripe,
1229                          "redundant stripe entry");
1230 fsck_err:
1231         return ret;
1232 }
1233
1234 void bch2_ptr_swab(struct bkey_s k)
1235 {
1236         struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
1237         union bch_extent_entry *entry;
1238         u64 *d;
1239
1240         for (d =  (u64 *) ptrs.start;
1241              d != (u64 *) ptrs.end;
1242              d++)
1243                 *d = swab64(*d);
1244
1245         for (entry = ptrs.start;
1246              entry < ptrs.end;
1247              entry = extent_entry_next(entry)) {
1248                 switch (extent_entry_type(entry)) {
1249                 case BCH_EXTENT_ENTRY_ptr:
1250                         break;
1251                 case BCH_EXTENT_ENTRY_crc32:
1252                         entry->crc32.csum = swab32(entry->crc32.csum);
1253                         break;
1254                 case BCH_EXTENT_ENTRY_crc64:
1255                         entry->crc64.csum_hi = swab16(entry->crc64.csum_hi);
1256                         entry->crc64.csum_lo = swab64(entry->crc64.csum_lo);
1257                         break;
1258                 case BCH_EXTENT_ENTRY_crc128:
1259                         entry->crc128.csum.hi = (__force __le64)
1260                                 swab64((__force u64) entry->crc128.csum.hi);
1261                         entry->crc128.csum.lo = (__force __le64)
1262                                 swab64((__force u64) entry->crc128.csum.lo);
1263                         break;
1264                 case BCH_EXTENT_ENTRY_stripe_ptr:
1265                         break;
1266                 case BCH_EXTENT_ENTRY_rebalance:
1267                         break;
1268                 }
1269         }
1270 }
1271
1272 const struct bch_extent_rebalance *bch2_bkey_rebalance_opts(struct bkey_s_c k)
1273 {
1274         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1275         const union bch_extent_entry *entry;
1276
1277         bkey_extent_entry_for_each(ptrs, entry)
1278                 if (__extent_entry_type(entry) == BCH_EXTENT_ENTRY_rebalance)
1279                         return &entry->rebalance;
1280
1281         return NULL;
1282 }
1283
1284 unsigned bch2_bkey_ptrs_need_rebalance(struct bch_fs *c, struct bkey_s_c k,
1285                                        unsigned target, unsigned compression)
1286 {
1287         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
1288         unsigned rewrite_ptrs = 0;
1289
1290         if (compression) {
1291                 unsigned compression_type = bch2_compression_opt_to_type(compression);
1292                 const union bch_extent_entry *entry;
1293                 struct extent_ptr_decoded p;
1294                 unsigned i = 0;
1295
1296                 bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
1297                         if (p.crc.compression_type == BCH_COMPRESSION_TYPE_incompressible) {
1298                                 rewrite_ptrs = 0;
1299                                 goto incompressible;
1300                         }
1301
1302                         if (!p.ptr.cached && p.crc.compression_type != compression_type)
1303                                 rewrite_ptrs |= 1U << i;
1304                         i++;
1305                 }
1306         }
1307 incompressible:
1308         if (target && bch2_target_accepts_data(c, BCH_DATA_user, target)) {
1309                 const struct bch_extent_ptr *ptr;
1310                 unsigned i = 0;
1311
1312                 bkey_for_each_ptr(ptrs, ptr) {
1313                         if (!ptr->cached && !bch2_dev_in_target(c, ptr->dev, target))
1314                                 rewrite_ptrs |= 1U << i;
1315                         i++;
1316                 }
1317         }
1318
1319         return rewrite_ptrs;
1320 }
1321
1322 bool bch2_bkey_needs_rebalance(struct bch_fs *c, struct bkey_s_c k)
1323 {
1324         const struct bch_extent_rebalance *r = bch2_bkey_rebalance_opts(k);
1325
1326         /*
1327          * If it's an indirect extent, we don't delete the rebalance entry when
1328          * done so that we know what options were applied - check if it still
1329          * needs work done:
1330          */
1331         if (r &&
1332             k.k->type == KEY_TYPE_reflink_v &&
1333             !bch2_bkey_ptrs_need_rebalance(c, k, r->target, r->compression))
1334                 r = NULL;
1335
1336         return r != NULL;
1337 }
1338
1339 int bch2_bkey_set_needs_rebalance(struct bch_fs *c, struct bkey_i *_k,
1340                                   unsigned target, unsigned compression)
1341 {
1342         struct bkey_s k = bkey_i_to_s(_k);
1343         struct bch_extent_rebalance *r;
1344         bool needs_rebalance;
1345
1346         if (!bkey_extent_is_direct_data(k.k))
1347                 return 0;
1348
1349         /* get existing rebalance entry: */
1350         r = (struct bch_extent_rebalance *) bch2_bkey_rebalance_opts(k.s_c);
1351         if (r) {
1352                 if (k.k->type == KEY_TYPE_reflink_v) {
1353                         /*
1354                          * indirect extents: existing options take precedence,
1355                          * so that we don't move extents back and forth if
1356                          * they're referenced by different inodes with different
1357                          * options:
1358                          */
1359                         if (r->target)
1360                                 target = r->target;
1361                         if (r->compression)
1362                                 compression = r->compression;
1363                 }
1364
1365                 r->target       = target;
1366                 r->compression  = compression;
1367         }
1368
1369         needs_rebalance = bch2_bkey_ptrs_need_rebalance(c, k.s_c, target, compression);
1370
1371         if (needs_rebalance && !r) {
1372                 union bch_extent_entry *new = bkey_val_end(k);
1373
1374                 new->rebalance.type             = 1U << BCH_EXTENT_ENTRY_rebalance;
1375                 new->rebalance.compression      = compression;
1376                 new->rebalance.target           = target;
1377                 new->rebalance.unused           = 0;
1378                 k.k->u64s += extent_entry_u64s(new);
1379         } else if (!needs_rebalance && r && k.k->type != KEY_TYPE_reflink_v) {
1380                 /*
1381                  * For indirect extents, don't delete the rebalance entry when
1382                  * we're finished so that we know we specifically moved it or
1383                  * compressed it to its current location/compression type
1384                  */
1385                 extent_entry_drop(k, (union bch_extent_entry *) r);
1386         }
1387
1388         return 0;
1389 }
1390
1391 /* Generic extent code: */
1392
1393 int bch2_cut_front_s(struct bpos where, struct bkey_s k)
1394 {
1395         unsigned new_val_u64s = bkey_val_u64s(k.k);
1396         int val_u64s_delta;
1397         u64 sub;
1398
1399         if (bkey_le(where, bkey_start_pos(k.k)))
1400                 return 0;
1401
1402         EBUG_ON(bkey_gt(where, k.k->p));
1403
1404         sub = where.offset - bkey_start_offset(k.k);
1405
1406         k.k->size -= sub;
1407
1408         if (!k.k->size) {
1409                 k.k->type = KEY_TYPE_deleted;
1410                 new_val_u64s = 0;
1411         }
1412
1413         switch (k.k->type) {
1414         case KEY_TYPE_extent:
1415         case KEY_TYPE_reflink_v: {
1416                 struct bkey_ptrs ptrs = bch2_bkey_ptrs(k);
1417                 union bch_extent_entry *entry;
1418                 bool seen_crc = false;
1419
1420                 bkey_extent_entry_for_each(ptrs, entry) {
1421                         switch (extent_entry_type(entry)) {
1422                         case BCH_EXTENT_ENTRY_ptr:
1423                                 if (!seen_crc)
1424                                         entry->ptr.offset += sub;
1425                                 break;
1426                         case BCH_EXTENT_ENTRY_crc32:
1427                                 entry->crc32.offset += sub;
1428                                 break;
1429                         case BCH_EXTENT_ENTRY_crc64:
1430                                 entry->crc64.offset += sub;
1431                                 break;
1432                         case BCH_EXTENT_ENTRY_crc128:
1433                                 entry->crc128.offset += sub;
1434                                 break;
1435                         case BCH_EXTENT_ENTRY_stripe_ptr:
1436                                 break;
1437                         case BCH_EXTENT_ENTRY_rebalance:
1438                                 break;
1439                         }
1440
1441                         if (extent_entry_is_crc(entry))
1442                                 seen_crc = true;
1443                 }
1444
1445                 break;
1446         }
1447         case KEY_TYPE_reflink_p: {
1448                 struct bkey_s_reflink_p p = bkey_s_to_reflink_p(k);
1449
1450                 le64_add_cpu(&p.v->idx, sub);
1451                 break;
1452         }
1453         case KEY_TYPE_inline_data:
1454         case KEY_TYPE_indirect_inline_data: {
1455                 void *p = bkey_inline_data_p(k);
1456                 unsigned bytes = bkey_inline_data_bytes(k.k);
1457
1458                 sub = min_t(u64, sub << 9, bytes);
1459
1460                 memmove(p, p + sub, bytes - sub);
1461
1462                 new_val_u64s -= sub >> 3;
1463                 break;
1464         }
1465         }
1466
1467         val_u64s_delta = bkey_val_u64s(k.k) - new_val_u64s;
1468         BUG_ON(val_u64s_delta < 0);
1469
1470         set_bkey_val_u64s(k.k, new_val_u64s);
1471         memset(bkey_val_end(k), 0, val_u64s_delta * sizeof(u64));
1472         return -val_u64s_delta;
1473 }
1474
1475 int bch2_cut_back_s(struct bpos where, struct bkey_s k)
1476 {
1477         unsigned new_val_u64s = bkey_val_u64s(k.k);
1478         int val_u64s_delta;
1479         u64 len = 0;
1480
1481         if (bkey_ge(where, k.k->p))
1482                 return 0;
1483
1484         EBUG_ON(bkey_lt(where, bkey_start_pos(k.k)));
1485
1486         len = where.offset - bkey_start_offset(k.k);
1487
1488         k.k->p.offset = where.offset;
1489         k.k->size = len;
1490
1491         if (!len) {
1492                 k.k->type = KEY_TYPE_deleted;
1493                 new_val_u64s = 0;
1494         }
1495
1496         switch (k.k->type) {
1497         case KEY_TYPE_inline_data:
1498         case KEY_TYPE_indirect_inline_data:
1499                 new_val_u64s = (bkey_inline_data_offset(k.k) +
1500                                 min(bkey_inline_data_bytes(k.k), k.k->size << 9)) >> 3;
1501                 break;
1502         }
1503
1504         val_u64s_delta = bkey_val_u64s(k.k) - new_val_u64s;
1505         BUG_ON(val_u64s_delta < 0);
1506
1507         set_bkey_val_u64s(k.k, new_val_u64s);
1508         memset(bkey_val_end(k), 0, val_u64s_delta * sizeof(u64));
1509         return -val_u64s_delta;
1510 }