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

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include "bcachefs.h"
   4 #include "alloc_foreground.h"
   5 #include "bkey_buf.h"
   6 #include "btree_update.h"
   7 #include "buckets.h"
   8 #include "data_update.h"
   9 #include "ec.h"
  10 #include "error.h"
  11 #include "extents.h"
  12 #include "io.h"
  13 #include "keylist.h"
  14 #include "move.h"
  15 #include "nocow_locking.h"
  16 #include "subvolume.h"
  17
  18 #include <trace/events/bcachefs.h>
  19
  20 static int insert_snapshot_whiteouts(struct btree_trans *trans,
  21                                      enum btree_id id,
  22                                      struct bpos old_pos,
  23                                      struct bpos new_pos)
  24 {
  25         struct bch_fs *c = trans->c;
  26         struct btree_iter iter, iter2;
  27         struct bkey_s_c k, k2;
  28         snapshot_id_list s;
  29         struct bkey_i *update;
  30         int ret;
  31
  32         if (!btree_type_has_snapshots(id))
  33                 return 0;
  34
  35         darray_init(&s);
  36
  37         if (!bch2_snapshot_has_children(c, old_pos.snapshot))
  38                 return 0;
  39
  40         bch2_trans_iter_init(trans, &iter, id, old_pos,
  41                              BTREE_ITER_NOT_EXTENTS|
  42                              BTREE_ITER_ALL_SNAPSHOTS);
  43         while (1) {
  44                 k = bch2_btree_iter_prev(&iter);
  45                 ret = bkey_err(k);
  46                 if (ret)
  47                         break;
  48
  49                 if (!k.k)
  50                         break;
  51
  52                 if (!bkey_eq(old_pos, k.k->p))
  53                         break;
  54
  55                 if (bch2_snapshot_is_ancestor(c, k.k->p.snapshot, old_pos.snapshot) &&
  56                     !snapshot_list_has_ancestor(c, &s, k.k->p.snapshot)) {
  57                         struct bpos whiteout_pos = new_pos;
  58
  59                         whiteout_pos.snapshot = k.k->p.snapshot;
  60
  61                         bch2_trans_iter_init(trans, &iter2, id, whiteout_pos,
  62                                              BTREE_ITER_NOT_EXTENTS|
  63                                              BTREE_ITER_INTENT);
  64                         k2 = bch2_btree_iter_peek_slot(&iter2);
  65                         ret = bkey_err(k2);
  66
  67                         if (!ret && k2.k->type == KEY_TYPE_deleted) {
  68                                 update = bch2_trans_kmalloc(trans, sizeof(struct bkey_i));
  69                                 ret = PTR_ERR_OR_ZERO(update);
  70                                 if (ret)
  71                                         break;
  72
  73                                 bkey_init(&update->k);
  74                                 update->k.p             = whiteout_pos;
  75                                 update->k.type          = KEY_TYPE_whiteout;
  76
  77                                 ret = bch2_trans_update(trans, &iter2, update,
  78                                                         BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE);
  79                         }
  80                         bch2_trans_iter_exit(trans, &iter2);
  81
  82                         if (ret)
  83                                 break;
  84
  85                         ret = snapshot_list_add(c, &s, k.k->p.snapshot);
  86                         if (ret)
  87                                 break;
  88                 }
  89         }
  90         bch2_trans_iter_exit(trans, &iter);
  91         darray_exit(&s);
  92
  93         return ret;
  94 }
  95
  96 static void trace_move_extent_fail2(struct data_update *m,
  97                          struct bkey_s_c new,
  98                          struct bkey_s_c wrote,
  99                          struct bkey_i *insert,
 100                          const char *msg)
 101 {
 102         struct bch_fs *c = m->op.c;
 103         struct bkey_s_c old = bkey_i_to_s_c(m->k.k);
 104         const union bch_extent_entry *entry;
 105         struct bch_extent_ptr *ptr;
 106         struct extent_ptr_decoded p;
 107         struct printbuf buf = PRINTBUF;
 108         unsigned i, rewrites_found = 0;
 109
 110         if (!trace_move_extent_fail_enabled())
 111                 return;
 112
 113         prt_str(&buf, msg);
 114
 115         if (insert) {
 116                 i = 0;
 117                 bkey_for_each_ptr_decode(old.k, bch2_bkey_ptrs_c(old), p, entry) {
 118                         struct bkey_s new_s;
 119                         new_s.k = (void *) new.k;
 120                         new_s.v = (void *) new.v;
 121
 122                         if (((1U << i) & m->data_opts.rewrite_ptrs) &&
 123                             (ptr = bch2_extent_has_ptr(old, p, bkey_i_to_s(insert))) &&
 124                             !ptr->cached)
 125                                 rewrites_found |= 1U << i;
 126                         i++;
 127                 }
 128         }
 129
 130         prt_printf(&buf, "\nrewrite ptrs:   %u%u%u%u",
 131                    (m->data_opts.rewrite_ptrs & (1 << 0)) != 0,
 132                    (m->data_opts.rewrite_ptrs & (1 << 1)) != 0,
 133                    (m->data_opts.rewrite_ptrs & (1 << 2)) != 0,
 134                    (m->data_opts.rewrite_ptrs & (1 << 3)) != 0);
 135
 136         prt_printf(&buf, "\nrewrites found: %u%u%u%u",
 137                    (rewrites_found & (1 << 0)) != 0,
 138                    (rewrites_found & (1 << 1)) != 0,
 139                    (rewrites_found & (1 << 2)) != 0,
 140                    (rewrites_found & (1 << 3)) != 0);
 141
 142         prt_str(&buf, "\nold:    ");
 143         bch2_bkey_val_to_text(&buf, c, old);
 144
 145         prt_str(&buf, "\nnew:    ");
 146         bch2_bkey_val_to_text(&buf, c, new);
 147
 148         prt_str(&buf, "\nwrote:  ");
 149         bch2_bkey_val_to_text(&buf, c, wrote);
 150
 151         if (insert) {
 152                 prt_str(&buf, "\ninsert: ");
 153                 bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(insert));
 154         }
 155
 156         trace_move_extent_fail(c, buf.buf);
 157         printbuf_exit(&buf);
 158 }
 159
 160 static int __bch2_data_update_index_update(struct btree_trans *trans,
 161                                            struct bch_write_op *op)
 162 {
 163         struct bch_fs *c = op->c;
 164         struct btree_iter iter;
 165         struct data_update *m =
 166                 container_of(op, struct data_update, op);
 167         struct keylist *keys = &op->insert_keys;
 168         struct bkey_buf _new, _insert;
 169         int ret = 0;
 170
 171         bch2_bkey_buf_init(&_new);
 172         bch2_bkey_buf_init(&_insert);
 173         bch2_bkey_buf_realloc(&_insert, c, U8_MAX);
 174
 175         bch2_trans_iter_init(trans, &iter, m->btree_id,
 176                              bkey_start_pos(&bch2_keylist_front(keys)->k),
 177                              BTREE_ITER_SLOTS|BTREE_ITER_INTENT);
 178
 179         while (1) {
 180                 struct bkey_s_c k;
 181                 struct bkey_s_c old = bkey_i_to_s_c(m->k.k);
 182                 struct bkey_i *insert = NULL;
 183                 struct bkey_i_extent *new;
 184                 const union bch_extent_entry *entry_c;
 185                 union bch_extent_entry *entry;
 186                 struct extent_ptr_decoded p;
 187                 struct bch_extent_ptr *ptr;
 188                 const struct bch_extent_ptr *ptr_c;
 189                 struct bpos next_pos;
 190                 bool should_check_enospc;
 191                 s64 i_sectors_delta = 0, disk_sectors_delta = 0;
 192                 unsigned rewrites_found = 0, durability, i;
 193
 194                 bch2_trans_begin(trans);
 195
 196                 k = bch2_btree_iter_peek_slot(&iter);
 197                 ret = bkey_err(k);
 198                 if (ret)
 199                         goto err;
 200
 201                 new = bkey_i_to_extent(bch2_keylist_front(keys));
 202
 203                 if (!bch2_extents_match(k, old)) {
 204                         trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i),
 205                                                 NULL, "no match:");
 206                         goto nowork;
 207                 }
 208
 209                 bkey_reassemble(_insert.k, k);
 210                 insert = _insert.k;
 211
 212                 bch2_bkey_buf_copy(&_new, c, bch2_keylist_front(keys));
 213                 new = bkey_i_to_extent(_new.k);
 214                 bch2_cut_front(iter.pos, &new->k_i);
 215
 216                 bch2_cut_front(iter.pos,        insert);
 217                 bch2_cut_back(new->k.p,         insert);
 218                 bch2_cut_back(insert->k.p,      &new->k_i);
 219
 220                 /*
 221                  * @old: extent that we read from
 222                  * @insert: key that we're going to update, initialized from
 223                  * extent currently in btree - same as @old unless we raced with
 224                  * other updates
 225                  * @new: extent with new pointers that we'll be adding to @insert
 226                  *
 227                  * Fist, drop rewrite_ptrs from @new:
 228                  */
 229                 i = 0;
 230                 bkey_for_each_ptr_decode(old.k, bch2_bkey_ptrs_c(old), p, entry_c) {
 231                         if (((1U << i) & m->data_opts.rewrite_ptrs) &&
 232                             (ptr = bch2_extent_has_ptr(old, p, bkey_i_to_s(insert))) &&
 233                             !ptr->cached) {
 234                                 bch2_bkey_drop_ptr_noerror(bkey_i_to_s(insert), ptr);
 235                                 /*
 236                                  * See comment below:
 237                                 bch2_extent_ptr_set_cached(bkey_i_to_s(insert), ptr);
 238                                 */
 239                                 rewrites_found |= 1U << i;
 240                         }
 241                         i++;
 242                 }
 243
 244                 if (m->data_opts.rewrite_ptrs &&
 245                     !rewrites_found &&
 246                     bch2_bkey_durability(c, k) >= m->op.opts.data_replicas) {
 247                         trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i), insert, "no rewrites found:");
 248                         goto nowork;
 249                 }
 250
 251                 /*
 252                  * A replica that we just wrote might conflict with a replica
 253                  * that we want to keep, due to racing with another move:
 254                  */
 255 restart_drop_conflicting_replicas:
 256                 extent_for_each_ptr(extent_i_to_s(new), ptr)
 257                         if ((ptr_c = bch2_bkey_has_device_c(bkey_i_to_s_c(insert), ptr->dev)) &&
 258                             !ptr_c->cached) {
 259                                 bch2_bkey_drop_ptr_noerror(bkey_i_to_s(&new->k_i), ptr);
 260                                 goto restart_drop_conflicting_replicas;
 261                         }
 262
 263                 if (!bkey_val_u64s(&new->k)) {
 264                         trace_move_extent_fail2(m, k, bkey_i_to_s_c(&new->k_i), insert, "new replicas conflicted:");
 265                         goto nowork;
 266                 }
 267
 268                 /* Now, drop pointers that conflict with what we just wrote: */
 269                 extent_for_each_ptr_decode(extent_i_to_s(new), p, entry)
 270                         if ((ptr = bch2_bkey_has_device(bkey_i_to_s(insert), p.ptr.dev)))
 271                                 bch2_bkey_drop_ptr_noerror(bkey_i_to_s(insert), ptr);
 272
 273                 durability = bch2_bkey_durability(c, bkey_i_to_s_c(insert)) +
 274                         bch2_bkey_durability(c, bkey_i_to_s_c(&new->k_i));
 275
 276                 /* Now, drop excess replicas: */
 277 restart_drop_extra_replicas:
 278                 bkey_for_each_ptr_decode(old.k, bch2_bkey_ptrs(bkey_i_to_s(insert)), p, entry) {
 279                         unsigned ptr_durability = bch2_extent_ptr_durability(c, &p);
 280
 281                         if (!p.ptr.cached &&
 282                             durability - ptr_durability >= m->op.opts.data_replicas) {
 283                                 durability -= ptr_durability;
 284                                 bch2_bkey_drop_ptr_noerror(bkey_i_to_s(insert), &entry->ptr);
 285                                 /*
 286                                  * Currently, we're dropping unneeded replicas
 287                                  * instead of marking them as cached, since
 288                                  * cached data in stripe buckets prevents them
 289                                  * from being reused:
 290                                 bch2_extent_ptr_set_cached(bkey_i_to_s(insert), &entry->ptr);
 291                                 */
 292                                 goto restart_drop_extra_replicas;
 293                         }
 294                 }
 295
 296                 /* Finally, add the pointers we just wrote: */
 297                 extent_for_each_ptr_decode(extent_i_to_s(new), p, entry)
 298                         bch2_extent_ptr_decoded_append(insert, &p);
 299
 300                 bch2_bkey_narrow_crcs(insert, (struct bch_extent_crc_unpacked) { 0 });
 301                 bch2_extent_normalize(c, bkey_i_to_s(insert));
 302
 303                 ret = bch2_sum_sector_overwrites(trans, &iter, insert,
 304                                                  &should_check_enospc,
 305                                                  &i_sectors_delta,
 306                                                  &disk_sectors_delta);
 307                 if (ret)
 308                         goto err;
 309
 310                 if (disk_sectors_delta > (s64) op->res.sectors) {
 311                         ret = bch2_disk_reservation_add(c, &op->res,
 312                                                 disk_sectors_delta - op->res.sectors,
 313                                                 !should_check_enospc
 314                                                 ? BCH_DISK_RESERVATION_NOFAIL : 0);
 315                         if (ret)
 316                                 goto out;
 317                 }
 318
 319                 next_pos = insert->k.p;
 320
 321                 if (!bkey_eq(bkey_start_pos(&insert->k), bkey_start_pos(k.k))) {
 322                         ret = insert_snapshot_whiteouts(trans, m->btree_id, k.k->p,
 323                                                         bkey_start_pos(&insert->k));
 324                         if (ret)
 325                                 goto err;
 326                 }
 327
 328                 if (!bkey_eq(insert->k.p, k.k->p)) {
 329                         ret = insert_snapshot_whiteouts(trans, m->btree_id,
 330                                                         k.k->p, insert->k.p);
 331                         if (ret)
 332                                 goto err;
 333                 }
 334
 335                 ret   = bch2_trans_update(trans, &iter, insert,
 336                                 BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE) ?:
 337                         bch2_trans_commit(trans, &op->res,
 338                                 NULL,
 339                                 BTREE_INSERT_NOCHECK_RW|
 340                                 BTREE_INSERT_NOFAIL|
 341                                 m->data_opts.btree_insert_flags);
 342                 if (!ret) {
 343                         bch2_btree_iter_set_pos(&iter, next_pos);
 344
 345                         this_cpu_add(c->counters[BCH_COUNTER_move_extent_finish], new->k.size);
 346                         trace_move_extent_finish(&new->k);
 347                 }
 348 err:
 349                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 350                         ret = 0;
 351                 if (ret)
 352                         break;
 353 next:
 354                 while (bkey_ge(iter.pos, bch2_keylist_front(keys)->k.p)) {
 355                         bch2_keylist_pop_front(keys);
 356                         if (bch2_keylist_empty(keys))
 357                                 goto out;
 358                 }
 359                 continue;
 360 nowork:
 361                 if (m->ctxt && m->ctxt->stats) {
 362                         BUG_ON(k.k->p.offset <= iter.pos.offset);
 363                         atomic64_inc(&m->ctxt->stats->keys_raced);
 364                         atomic64_add(k.k->p.offset - iter.pos.offset,
 365                                      &m->ctxt->stats->sectors_raced);
 366                 }
 367
 368                 this_cpu_add(c->counters[BCH_COUNTER_move_extent_fail], new->k.size);
 369
 370                 bch2_btree_iter_advance(&iter);
 371                 goto next;
 372         }
 373 out:
 374         bch2_trans_iter_exit(trans, &iter);
 375         bch2_bkey_buf_exit(&_insert, c);
 376         bch2_bkey_buf_exit(&_new, c);
 377         BUG_ON(bch2_err_matches(ret, BCH_ERR_transaction_restart));
 378         return ret;
 379 }
 380
 381 int bch2_data_update_index_update(struct bch_write_op *op)
 382 {
 383         return bch2_trans_run(op->c, __bch2_data_update_index_update(&trans, op));
 384 }
 385
 386 void bch2_data_update_read_done(struct data_update *m,
 387                                 struct bch_extent_crc_unpacked crc)
 388 {
 389         /* write bio must own pages: */
 390         BUG_ON(!m->op.wbio.bio.bi_vcnt);
 391
 392         m->op.crc = crc;
 393         m->op.wbio.bio.bi_iter.bi_size = crc.compressed_size << 9;
 394
 395         closure_call(&m->op.cl, bch2_write, NULL, NULL);
 396 }
 397
 398 void bch2_data_update_exit(struct data_update *update)
 399 {
 400         struct bch_fs *c = update->op.c;
 401         struct bkey_ptrs_c ptrs =
 402                 bch2_bkey_ptrs_c(bkey_i_to_s_c(update->k.k));
 403         const struct bch_extent_ptr *ptr;
 404
 405         bkey_for_each_ptr(ptrs, ptr) {
 406                 if (c->opts.nocow_enabled)
 407                         bch2_bucket_nocow_unlock(&c->nocow_locks,
 408                                                  PTR_BUCKET_POS(c, ptr), 0);
 409                 percpu_ref_put(&bch_dev_bkey_exists(c, ptr->dev)->ref);
 410         }
 411
 412         bch2_bkey_buf_exit(&update->k, c);
 413         bch2_disk_reservation_put(c, &update->op.res);
 414         bch2_bio_free_pages_pool(c, &update->op.wbio.bio);
 415 }
 416
 417 void bch2_update_unwritten_extent(struct btree_trans *trans,
 418                                   struct data_update *update)
 419 {
 420         struct bch_fs *c = update->op.c;
 421         struct bio *bio = &update->op.wbio.bio;
 422         struct bkey_i_extent *e;
 423         struct write_point *wp;
 424         struct bch_extent_ptr *ptr;
 425         struct closure cl;
 426         struct btree_iter iter;
 427         struct bkey_s_c k;
 428         int ret;
 429
 430         closure_init_stack(&cl);
 431         bch2_keylist_init(&update->op.insert_keys, update->op.inline_keys);
 432
 433         while (bio_sectors(bio)) {
 434                 unsigned sectors = bio_sectors(bio);
 435
 436                 bch2_trans_iter_init(trans, &iter, update->btree_id, update->op.pos,
 437                                      BTREE_ITER_SLOTS);
 438                 ret = lockrestart_do(trans, ({
 439                         k = bch2_btree_iter_peek_slot(&iter);
 440                         bkey_err(k);
 441                 }));
 442                 bch2_trans_iter_exit(trans, &iter);
 443
 444                 if (ret || !bch2_extents_match(k, bkey_i_to_s_c(update->k.k)))
 445                         break;
 446
 447                 e = bkey_extent_init(update->op.insert_keys.top);
 448                 e->k.p = update->op.pos;
 449
 450                 ret = bch2_alloc_sectors_start_trans(trans,
 451                                 update->op.target,
 452                                 false,
 453                                 update->op.write_point,
 454                                 &update->op.devs_have,
 455                                 update->op.nr_replicas,
 456                                 update->op.nr_replicas,
 457                                 update->op.alloc_reserve,
 458                                 0, &cl, &wp);
 459                 if (bch2_err_matches(ret, BCH_ERR_operation_blocked)) {
 460                         bch2_trans_unlock(trans);
 461                         closure_sync(&cl);
 462                         continue;
 463                 }
 464
 465                 if (ret)
 466                         return;
 467
 468                 sectors = min(sectors, wp->sectors_free);
 469
 470                 bch2_key_resize(&e->k, sectors);
 471
 472                 bch2_open_bucket_get(c, wp, &update->op.open_buckets);
 473                 bch2_alloc_sectors_append_ptrs(c, wp, &e->k_i, sectors, false);
 474                 bch2_alloc_sectors_done(c, wp);
 475
 476                 bio_advance(bio, sectors << 9);
 477                 update->op.pos.offset += sectors;
 478
 479                 extent_for_each_ptr(extent_i_to_s(e), ptr)
 480                         ptr->unwritten = true;
 481                 bch2_keylist_push(&update->op.insert_keys);
 482
 483                 ret = __bch2_data_update_index_update(trans, &update->op);
 484
 485                 bch2_open_buckets_put(c, &update->op.open_buckets);
 486
 487                 if (ret)
 488                         break;
 489         }
 490
 491         if ((atomic_read(&cl.remaining) & CLOSURE_REMAINING_MASK) != 1) {
 492                 bch2_trans_unlock(trans);
 493                 closure_sync(&cl);
 494         }
 495 }
 496
 497 int bch2_data_update_init(struct btree_trans *trans,
 498                           struct moving_context *ctxt,
 499                           struct data_update *m,
 500                           struct write_point_specifier wp,
 501                           struct bch_io_opts io_opts,
 502                           struct data_update_opts data_opts,
 503                           enum btree_id btree_id,
 504                           struct bkey_s_c k)
 505 {
 506         struct bch_fs *c = trans->c;
 507         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 508         const union bch_extent_entry *entry;
 509         struct extent_ptr_decoded p;
 510         const struct bch_extent_ptr *ptr;
 511         unsigned i, reserve_sectors = k.k->size * data_opts.extra_replicas;
 512         unsigned ptrs_locked = 0;
 513         int ret;
 514
 515         bch2_bkey_buf_init(&m->k);
 516         bch2_bkey_buf_reassemble(&m->k, c, k);
 517         m->btree_id     = btree_id;
 518         m->data_opts    = data_opts;
 519
 520         bch2_write_op_init(&m->op, c, io_opts);
 521         m->op.pos       = bkey_start_pos(k.k);
 522         m->op.version   = k.k->version;
 523         m->op.target    = data_opts.target;
 524         m->op.write_point = wp;
 525         m->op.nr_replicas = 0;
 526         m->op.flags     |= BCH_WRITE_PAGES_STABLE|
 527                 BCH_WRITE_PAGES_OWNED|
 528                 BCH_WRITE_DATA_ENCODED|
 529                 BCH_WRITE_MOVE|
 530                 m->data_opts.write_flags;
 531         m->op.compression_type =
 532                 bch2_compression_opt_to_type[io_opts.background_compression ?:
 533                                              io_opts.compression];
 534         if (m->data_opts.btree_insert_flags & BTREE_INSERT_USE_RESERVE)
 535                 m->op.alloc_reserve = RESERVE_movinggc;
 536
 537         bkey_for_each_ptr(ptrs, ptr)
 538                 percpu_ref_get(&bch_dev_bkey_exists(c, ptr->dev)->ref);
 539
 540         i = 0;
 541         bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
 542                 bool locked;
 543
 544                 if (((1U << i) & m->data_opts.rewrite_ptrs)) {
 545                         BUG_ON(p.ptr.cached);
 546
 547                         if (crc_is_compressed(p.crc))
 548                                 reserve_sectors += k.k->size;
 549
 550                         m->op.nr_replicas += bch2_extent_ptr_durability(c, &p);
 551                 } else if (!p.ptr.cached) {
 552                         bch2_dev_list_add_dev(&m->op.devs_have, p.ptr.dev);
 553                 }
 554
 555                 /*
 556                  * op->csum_type is normally initialized from the fs/file's
 557                  * current options - but if an extent is encrypted, we require
 558                  * that it stays encrypted:
 559                  */
 560                 if (bch2_csum_type_is_encryption(p.crc.csum_type)) {
 561                         m->op.nonce     = p.crc.nonce + p.crc.offset;
 562                         m->op.csum_type = p.crc.csum_type;
 563                 }
 564
 565                 if (p.crc.compression_type == BCH_COMPRESSION_TYPE_incompressible)
 566                         m->op.incompressible = true;
 567
 568                 if (c->opts.nocow_enabled) {
 569                         if (ctxt) {
 570                                 move_ctxt_wait_event(ctxt, trans,
 571                                                 (locked = bch2_bucket_nocow_trylock(&c->nocow_locks,
 572                                                                           PTR_BUCKET_POS(c, &p.ptr), 0)) ||
 573                                                 !atomic_read(&ctxt->read_sectors));
 574
 575                                 if (!locked)
 576                                         bch2_bucket_nocow_lock(&c->nocow_locks,
 577                                                                PTR_BUCKET_POS(c, &p.ptr), 0);
 578                         } else {
 579                                 if (!bch2_bucket_nocow_trylock(&c->nocow_locks,
 580                                                                PTR_BUCKET_POS(c, &p.ptr), 0)) {
 581                                         ret = -BCH_ERR_nocow_lock_blocked;
 582                                         goto err;
 583                                 }
 584                         }
 585                         ptrs_locked |= (1U << i);
 586                 }
 587
 588                 i++;
 589         }
 590
 591         if (reserve_sectors) {
 592                 ret = bch2_disk_reservation_add(c, &m->op.res, reserve_sectors,
 593                                 m->data_opts.extra_replicas
 594                                 ? 0
 595                                 : BCH_DISK_RESERVATION_NOFAIL);
 596                 if (ret)
 597                         goto err;
 598         }
 599
 600         m->op.nr_replicas += m->data_opts.extra_replicas;
 601         m->op.nr_replicas_required = m->op.nr_replicas;
 602
 603         BUG_ON(!m->op.nr_replicas);
 604
 605         /* Special handling required: */
 606         if (bkey_extent_is_unwritten(k))
 607                 return -BCH_ERR_unwritten_extent_update;
 608         return 0;
 609 err:
 610         i = 0;
 611         bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
 612                 if ((1U << i) & ptrs_locked)
 613                         bch2_bucket_nocow_unlock(&c->nocow_locks,
 614                                                  PTR_BUCKET_POS(c, &p.ptr), 0);
 615                 percpu_ref_put(&bch_dev_bkey_exists(c, p.ptr.dev)->ref);
 616                 i++;
 617         }
 618
 619         bch2_bkey_buf_exit(&m->k, c);
 620         bch2_bio_free_pages_pool(c, &m->op.wbio.bio);
 621         return ret;
 622 }
 623
 624 void bch2_data_update_opts_normalize(struct bkey_s_c k, struct data_update_opts *opts)
 625 {
 626         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 627         const struct bch_extent_ptr *ptr;
 628         unsigned i = 0;
 629
 630         bkey_for_each_ptr(ptrs, ptr) {
 631                 if ((opts->rewrite_ptrs & (1U << i)) && ptr->cached) {
 632                         opts->kill_ptrs |= 1U << i;
 633                         opts->rewrite_ptrs ^= 1U << i;
 634                 }
 635
 636                 i++;
 637         }
 638 }