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

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * bcachefs setup/teardown code, and some metadata io - read a superblock and
   4  * figure out what to do with it.
   5  *
   6  * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
   7  * Copyright 2012 Google, Inc.
   8  */
   9
  10 #include "bcachefs.h"
  11 #include "alloc_background.h"
  12 #include "alloc_foreground.h"
  13 #include "bkey_sort.h"
  14 #include "btree_cache.h"
  15 #include "btree_gc.h"
  16 #include "btree_key_cache.h"
  17 #include "btree_update_interior.h"
  18 #include "btree_io.h"
  19 #include "btree_write_buffer.h"
  20 #include "buckets_waiting_for_journal.h"
  21 #include "chardev.h"
  22 #include "checksum.h"
  23 #include "clock.h"
  24 #include "compress.h"
  25 #include "counters.h"
  26 #include "debug.h"
  27 #include "disk_groups.h"
  28 #include "ec.h"
  29 #include "errcode.h"
  30 #include "error.h"
  31 #include "fs.h"
  32 #include "fs-io.h"
  33 #include "fsck.h"
  34 #include "inode.h"
  35 #include "io.h"
  36 #include "journal.h"
  37 #include "journal_reclaim.h"
  38 #include "journal_seq_blacklist.h"
  39 #include "move.h"
  40 #include "migrate.h"
  41 #include "movinggc.h"
  42 #include "nocow_locking.h"
  43 #include "quota.h"
  44 #include "rebalance.h"
  45 #include "recovery.h"
  46 #include "replicas.h"
  47 #include "subvolume.h"
  48 #include "super.h"
  49 #include "super-io.h"
  50 #include "sysfs.h"
  51 #include "trace.h"
  52
  53 #include <linux/backing-dev.h>
  54 #include <linux/blkdev.h>
  55 #include <linux/debugfs.h>
  56 #include <linux/device.h>
  57 #include <linux/idr.h>
  58 #include <linux/module.h>
  59 #include <linux/percpu.h>
  60 #include <linux/random.h>
  61 #include <linux/sysfs.h>
  62 #include <crypto/hash.h>
  63
  64 MODULE_LICENSE("GPL");
  65 MODULE_AUTHOR("Kent Overstreet <kent.overstreet@gmail.com>");
  66
  67 #define KTYPE(type)                                                     \
  68 static const struct attribute_group type ## _group = {                  \
  69         .attrs = type ## _files                                         \
  70 };                                                                      \
  71                                                                         \
  72 static const struct attribute_group *type ## _groups[] = {              \
  73         &type ## _group,                                                \
  74         NULL                                                            \
  75 };                                                                      \
  76                                                                         \
  77 static const struct kobj_type type ## _ktype = {                        \
  78         .release        = type ## _release,                             \
  79         .sysfs_ops      = &type ## _sysfs_ops,                          \
  80         .default_groups = type ## _groups                               \
  81 }
  82
  83 static void bch2_fs_release(struct kobject *);
  84 static void bch2_dev_release(struct kobject *);
  85 static void bch2_fs_counters_release(struct kobject *k)
  86 {
  87 }
  88
  89 static void bch2_fs_internal_release(struct kobject *k)
  90 {
  91 }
  92
  93 static void bch2_fs_opts_dir_release(struct kobject *k)
  94 {
  95 }
  96
  97 static void bch2_fs_time_stats_release(struct kobject *k)
  98 {
  99 }
 100
 101 KTYPE(bch2_fs);
 102 KTYPE(bch2_fs_counters);
 103 KTYPE(bch2_fs_internal);
 104 KTYPE(bch2_fs_opts_dir);
 105 KTYPE(bch2_fs_time_stats);
 106 KTYPE(bch2_dev);
 107
 108 static struct kset *bcachefs_kset;
 109 static LIST_HEAD(bch_fs_list);
 110 static DEFINE_MUTEX(bch_fs_list_lock);
 111
 112 DECLARE_WAIT_QUEUE_HEAD(bch2_read_only_wait);
 113
 114 static void bch2_dev_free(struct bch_dev *);
 115 static int bch2_dev_alloc(struct bch_fs *, unsigned);
 116 static int bch2_dev_sysfs_online(struct bch_fs *, struct bch_dev *);
 117 static void __bch2_dev_read_only(struct bch_fs *, struct bch_dev *);
 118
 119 struct bch_fs *bch2_dev_to_fs(dev_t dev)
 120 {
 121         struct bch_fs *c;
 122         struct bch_dev *ca;
 123         unsigned i;
 124
 125         mutex_lock(&bch_fs_list_lock);
 126         rcu_read_lock();
 127
 128         list_for_each_entry(c, &bch_fs_list, list)
 129                 for_each_member_device_rcu(ca, c, i, NULL)
 130                         if (ca->disk_sb.bdev && ca->disk_sb.bdev->bd_dev == dev) {
 131                                 closure_get(&c->cl);
 132                                 goto found;
 133                         }
 134         c = NULL;
 135 found:
 136         rcu_read_unlock();
 137         mutex_unlock(&bch_fs_list_lock);
 138
 139         return c;
 140 }
 141
 142 static struct bch_fs *__bch2_uuid_to_fs(__uuid_t uuid)
 143 {
 144         struct bch_fs *c;
 145
 146         lockdep_assert_held(&bch_fs_list_lock);
 147
 148         list_for_each_entry(c, &bch_fs_list, list)
 149                 if (!memcmp(&c->disk_sb.sb->uuid, &uuid, sizeof(uuid)))
 150                         return c;
 151
 152         return NULL;
 153 }
 154
 155 struct bch_fs *bch2_uuid_to_fs(__uuid_t uuid)
 156 {
 157         struct bch_fs *c;
 158
 159         mutex_lock(&bch_fs_list_lock);
 160         c = __bch2_uuid_to_fs(uuid);
 161         if (c)
 162                 closure_get(&c->cl);
 163         mutex_unlock(&bch_fs_list_lock);
 164
 165         return c;
 166 }
 167
 168 static void bch2_dev_usage_journal_reserve(struct bch_fs *c)
 169 {
 170         struct bch_dev *ca;
 171         unsigned i, nr = 0, u64s =
 172                 ((sizeof(struct jset_entry_dev_usage) +
 173                   sizeof(struct jset_entry_dev_usage_type) * BCH_DATA_NR)) /
 174                 sizeof(u64);
 175
 176         rcu_read_lock();
 177         for_each_member_device_rcu(ca, c, i, NULL)
 178                 nr++;
 179         rcu_read_unlock();
 180
 181         bch2_journal_entry_res_resize(&c->journal,
 182                         &c->dev_usage_journal_res, u64s * nr);
 183 }
 184
 185 /* Filesystem RO/RW: */
 186
 187 /*
 188  * For startup/shutdown of RW stuff, the dependencies are:
 189  *
 190  * - foreground writes depend on copygc and rebalance (to free up space)
 191  *
 192  * - copygc and rebalance depend on mark and sweep gc (they actually probably
 193  *   don't because they either reserve ahead of time or don't block if
 194  *   allocations fail, but allocations can require mark and sweep gc to run
 195  *   because of generation number wraparound)
 196  *
 197  * - all of the above depends on the allocator threads
 198  *
 199  * - allocator depends on the journal (when it rewrites prios and gens)
 200  */
 201
 202 static void __bch2_fs_read_only(struct bch_fs *c)
 203 {
 204         struct bch_dev *ca;
 205         unsigned i, clean_passes = 0;
 206         u64 seq = 0;
 207
 208         bch2_fs_ec_stop(c);
 209         bch2_open_buckets_stop(c, NULL, true);
 210         bch2_rebalance_stop(c);
 211         bch2_copygc_stop(c);
 212         bch2_gc_thread_stop(c);
 213         bch2_fs_ec_flush(c);
 214
 215         bch_verbose(c, "flushing journal and stopping allocators, journal seq %llu",
 216                     journal_cur_seq(&c->journal));
 217
 218         do {
 219                 clean_passes++;
 220
 221                 if (bch2_btree_interior_updates_flush(c) ||
 222                     bch2_journal_flush_all_pins(&c->journal) ||
 223                     bch2_btree_flush_all_writes(c) ||
 224                     seq != atomic64_read(&c->journal.seq)) {
 225                         seq = atomic64_read(&c->journal.seq);
 226                         clean_passes = 0;
 227                 }
 228         } while (clean_passes < 2);
 229
 230         bch_verbose(c, "flushing journal and stopping allocators complete, journal seq %llu",
 231                     journal_cur_seq(&c->journal));
 232
 233         if (test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags) &&
 234             !test_bit(BCH_FS_EMERGENCY_RO, &c->flags))
 235                 set_bit(BCH_FS_CLEAN_SHUTDOWN, &c->flags);
 236         bch2_fs_journal_stop(&c->journal);
 237
 238         /*
 239          * After stopping journal:
 240          */
 241         for_each_member_device(ca, c, i)
 242                 bch2_dev_allocator_remove(c, ca);
 243 }
 244
 245 #ifndef BCH_WRITE_REF_DEBUG
 246 static void bch2_writes_disabled(struct percpu_ref *writes)
 247 {
 248         struct bch_fs *c = container_of(writes, struct bch_fs, writes);
 249
 250         set_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags);
 251         wake_up(&bch2_read_only_wait);
 252 }
 253 #endif
 254
 255 void bch2_fs_read_only(struct bch_fs *c)
 256 {
 257         if (!test_bit(BCH_FS_RW, &c->flags)) {
 258                 bch2_journal_reclaim_stop(&c->journal);
 259                 return;
 260         }
 261
 262         BUG_ON(test_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags));
 263
 264         /*
 265          * Block new foreground-end write operations from starting - any new
 266          * writes will return -EROFS:
 267          */
 268         set_bit(BCH_FS_GOING_RO, &c->flags);
 269 #ifndef BCH_WRITE_REF_DEBUG
 270         percpu_ref_kill(&c->writes);
 271 #else
 272         for (unsigned i = 0; i < BCH_WRITE_REF_NR; i++)
 273                 bch2_write_ref_put(c, i);
 274 #endif
 275
 276         /*
 277          * If we're not doing an emergency shutdown, we want to wait on
 278          * outstanding writes to complete so they don't see spurious errors due
 279          * to shutting down the allocator:
 280          *
 281          * If we are doing an emergency shutdown outstanding writes may
 282          * hang until we shutdown the allocator so we don't want to wait
 283          * on outstanding writes before shutting everything down - but
 284          * we do need to wait on them before returning and signalling
 285          * that going RO is complete:
 286          */
 287         wait_event(bch2_read_only_wait,
 288                    test_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags) ||
 289                    test_bit(BCH_FS_EMERGENCY_RO, &c->flags));
 290
 291         __bch2_fs_read_only(c);
 292
 293         wait_event(bch2_read_only_wait,
 294                    test_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags));
 295
 296         clear_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags);
 297         clear_bit(BCH_FS_GOING_RO, &c->flags);
 298
 299         if (!bch2_journal_error(&c->journal) &&
 300             !test_bit(BCH_FS_ERROR, &c->flags) &&
 301             !test_bit(BCH_FS_EMERGENCY_RO, &c->flags) &&
 302             test_bit(BCH_FS_STARTED, &c->flags) &&
 303             test_bit(BCH_FS_CLEAN_SHUTDOWN, &c->flags) &&
 304             !c->opts.norecovery) {
 305                 BUG_ON(c->journal.last_empty_seq != journal_cur_seq(&c->journal));
 306                 BUG_ON(atomic_read(&c->btree_cache.dirty));
 307                 BUG_ON(atomic_long_read(&c->btree_key_cache.nr_dirty));
 308                 BUG_ON(c->btree_write_buffer.state.nr);
 309
 310                 bch_verbose(c, "marking filesystem clean");
 311                 bch2_fs_mark_clean(c);
 312         }
 313
 314         clear_bit(BCH_FS_RW, &c->flags);
 315 }
 316
 317 static void bch2_fs_read_only_work(struct work_struct *work)
 318 {
 319         struct bch_fs *c =
 320                 container_of(work, struct bch_fs, read_only_work);
 321
 322         down_write(&c->state_lock);
 323         bch2_fs_read_only(c);
 324         up_write(&c->state_lock);
 325 }
 326
 327 static void bch2_fs_read_only_async(struct bch_fs *c)
 328 {
 329         queue_work(system_long_wq, &c->read_only_work);
 330 }
 331
 332 bool bch2_fs_emergency_read_only(struct bch_fs *c)
 333 {
 334         bool ret = !test_and_set_bit(BCH_FS_EMERGENCY_RO, &c->flags);
 335
 336         bch2_journal_halt(&c->journal);
 337         bch2_fs_read_only_async(c);
 338
 339         wake_up(&bch2_read_only_wait);
 340         return ret;
 341 }
 342
 343 static int bch2_fs_read_write_late(struct bch_fs *c)
 344 {
 345         int ret;
 346
 347         ret = bch2_rebalance_start(c);
 348         if (ret) {
 349                 bch_err(c, "error starting rebalance thread");
 350                 return ret;
 351         }
 352
 353         return 0;
 354 }
 355
 356 static int __bch2_fs_read_write(struct bch_fs *c, bool early)
 357 {
 358         struct bch_dev *ca;
 359         unsigned i;
 360         int ret;
 361
 362         if (test_bit(BCH_FS_INITIAL_GC_UNFIXED, &c->flags)) {
 363                 bch_err(c, "cannot go rw, unfixed btree errors");
 364                 return -EROFS;
 365         }
 366
 367         if (test_bit(BCH_FS_RW, &c->flags))
 368                 return 0;
 369
 370         /*
 371          * nochanges is used for fsck -n mode - we have to allow going rw
 372          * during recovery for that to work:
 373          */
 374         if (c->opts.norecovery ||
 375             (c->opts.nochanges &&
 376              (!early || c->opts.read_only)))
 377                 return -EROFS;
 378
 379         bch_info(c, "going read-write");
 380
 381         ret = bch2_fs_mark_dirty(c);
 382         if (ret)
 383                 goto err;
 384
 385         clear_bit(BCH_FS_CLEAN_SHUTDOWN, &c->flags);
 386
 387         /*
 388          * First journal write must be a flush write: after a clean shutdown we
 389          * don't read the journal, so the first journal write may end up
 390          * overwriting whatever was there previously, and there must always be
 391          * at least one non-flush write in the journal or recovery will fail:
 392          */
 393         set_bit(JOURNAL_NEED_FLUSH_WRITE, &c->journal.flags);
 394
 395         for_each_rw_member(ca, c, i)
 396                 bch2_dev_allocator_add(c, ca);
 397         bch2_recalc_capacity(c);
 398
 399         ret = bch2_gc_thread_start(c);
 400         if (ret) {
 401                 bch_err(c, "error starting gc thread");
 402                 return ret;
 403         }
 404
 405         ret = bch2_copygc_start(c);
 406         if (ret) {
 407                 bch_err(c, "error starting copygc thread");
 408                 return ret;
 409         }
 410
 411         if (!early) {
 412                 ret = bch2_fs_read_write_late(c);
 413                 if (ret)
 414                         goto err;
 415         }
 416
 417 #ifndef BCH_WRITE_REF_DEBUG
 418         percpu_ref_reinit(&c->writes);
 419 #else
 420         for (unsigned i = 0; i < BCH_WRITE_REF_NR; i++) {
 421                 BUG_ON(atomic_long_read(&c->writes[i]));
 422                 atomic_long_inc(&c->writes[i]);
 423         }
 424 #endif
 425         set_bit(BCH_FS_RW, &c->flags);
 426         set_bit(BCH_FS_WAS_RW, &c->flags);
 427
 428         bch2_do_discards(c);
 429         bch2_do_invalidates(c);
 430         bch2_do_stripe_deletes(c);
 431         bch2_do_pending_node_rewrites(c);
 432         return 0;
 433 err:
 434         __bch2_fs_read_only(c);
 435         return ret;
 436 }
 437
 438 int bch2_fs_read_write(struct bch_fs *c)
 439 {
 440         return __bch2_fs_read_write(c, false);
 441 }
 442
 443 int bch2_fs_read_write_early(struct bch_fs *c)
 444 {
 445         lockdep_assert_held(&c->state_lock);
 446
 447         return __bch2_fs_read_write(c, true);
 448 }
 449
 450 /* Filesystem startup/shutdown: */
 451
 452 static void __bch2_fs_free(struct bch_fs *c)
 453 {
 454         unsigned i;
 455         int cpu;
 456
 457         for (i = 0; i < BCH_TIME_STAT_NR; i++)
 458                 bch2_time_stats_exit(&c->times[i]);
 459
 460         bch2_free_pending_node_rewrites(c);
 461         bch2_fs_counters_exit(c);
 462         bch2_fs_snapshots_exit(c);
 463         bch2_fs_quota_exit(c);
 464         bch2_fs_fsio_exit(c);
 465         bch2_fs_ec_exit(c);
 466         bch2_fs_encryption_exit(c);
 467         bch2_fs_io_exit(c);
 468         bch2_fs_buckets_waiting_for_journal_exit(c);
 469         bch2_fs_btree_interior_update_exit(c);
 470         bch2_fs_btree_iter_exit(c);
 471         bch2_fs_btree_key_cache_exit(&c->btree_key_cache);
 472         bch2_fs_btree_cache_exit(c);
 473         bch2_fs_replicas_exit(c);
 474         bch2_fs_journal_exit(&c->journal);
 475         bch2_io_clock_exit(&c->io_clock[WRITE]);
 476         bch2_io_clock_exit(&c->io_clock[READ]);
 477         bch2_fs_compress_exit(c);
 478         bch2_journal_keys_free(&c->journal_keys);
 479         bch2_journal_entries_free(c);
 480         bch2_fs_btree_write_buffer_exit(c);
 481         percpu_free_rwsem(&c->mark_lock);
 482         free_percpu(c->online_reserved);
 483
 484         if (c->btree_paths_bufs)
 485                 for_each_possible_cpu(cpu)
 486                         kfree(per_cpu_ptr(c->btree_paths_bufs, cpu)->path);
 487
 488         free_percpu(c->btree_paths_bufs);
 489         free_percpu(c->pcpu);
 490         mempool_exit(&c->large_bkey_pool);
 491         mempool_exit(&c->btree_bounce_pool);
 492         bioset_exit(&c->btree_bio);
 493         mempool_exit(&c->fill_iter);
 494 #ifndef BCH_WRITE_REF_DEBUG
 495         percpu_ref_exit(&c->writes);
 496 #endif
 497         kfree(rcu_dereference_protected(c->disk_groups, 1));
 498         kfree(c->journal_seq_blacklist_table);
 499         kfree(c->unused_inode_hints);
 500
 501         if (c->write_ref_wq)
 502                 destroy_workqueue(c->write_ref_wq);
 503         if (c->io_complete_wq)
 504                 destroy_workqueue(c->io_complete_wq);
 505         if (c->copygc_wq)
 506                 destroy_workqueue(c->copygc_wq);
 507         if (c->btree_io_complete_wq)
 508                 destroy_workqueue(c->btree_io_complete_wq);
 509         if (c->btree_update_wq)
 510                 destroy_workqueue(c->btree_update_wq);
 511
 512         bch2_free_super(&c->disk_sb);
 513         kvpfree(c, sizeof(*c));
 514         module_put(THIS_MODULE);
 515 }
 516
 517 static void bch2_fs_release(struct kobject *kobj)
 518 {
 519         struct bch_fs *c = container_of(kobj, struct bch_fs, kobj);
 520
 521         __bch2_fs_free(c);
 522 }
 523
 524 void __bch2_fs_stop(struct bch_fs *c)
 525 {
 526         struct bch_dev *ca;
 527         unsigned i;
 528
 529         bch_verbose(c, "shutting down");
 530
 531         set_bit(BCH_FS_STOPPING, &c->flags);
 532
 533         cancel_work_sync(&c->journal_seq_blacklist_gc_work);
 534
 535         down_write(&c->state_lock);
 536         bch2_fs_read_only(c);
 537         up_write(&c->state_lock);
 538
 539         for_each_member_device(ca, c, i)
 540                 if (ca->kobj.state_in_sysfs &&
 541                     ca->disk_sb.bdev)
 542                         sysfs_remove_link(bdev_kobj(ca->disk_sb.bdev), "bcachefs");
 543
 544         if (c->kobj.state_in_sysfs)
 545                 kobject_del(&c->kobj);
 546
 547         bch2_fs_debug_exit(c);
 548         bch2_fs_chardev_exit(c);
 549
 550         kobject_put(&c->counters_kobj);
 551         kobject_put(&c->time_stats);
 552         kobject_put(&c->opts_dir);
 553         kobject_put(&c->internal);
 554
 555         /* btree prefetch might have kicked off reads in the background: */
 556         bch2_btree_flush_all_reads(c);
 557
 558         for_each_member_device(ca, c, i)
 559                 cancel_work_sync(&ca->io_error_work);
 560
 561         cancel_work_sync(&c->read_only_work);
 562
 563         for (i = 0; i < c->sb.nr_devices; i++)
 564                 if (c->devs[i])
 565                         bch2_free_super(&c->devs[i]->disk_sb);
 566 }
 567
 568 void bch2_fs_free(struct bch_fs *c)
 569 {
 570         unsigned i;
 571
 572         mutex_lock(&bch_fs_list_lock);
 573         list_del(&c->list);
 574         mutex_unlock(&bch_fs_list_lock);
 575
 576         closure_sync(&c->cl);
 577         closure_debug_destroy(&c->cl);
 578
 579         for (i = 0; i < c->sb.nr_devices; i++)
 580                 if (c->devs[i])
 581                         bch2_dev_free(rcu_dereference_protected(c->devs[i], 1));
 582
 583         bch_verbose(c, "shutdown complete");
 584
 585         kobject_put(&c->kobj);
 586 }
 587
 588 void bch2_fs_stop(struct bch_fs *c)
 589 {
 590         __bch2_fs_stop(c);
 591         bch2_fs_free(c);
 592 }
 593
 594 static int bch2_fs_online(struct bch_fs *c)
 595 {
 596         struct bch_dev *ca;
 597         unsigned i;
 598         int ret = 0;
 599
 600         lockdep_assert_held(&bch_fs_list_lock);
 601
 602         if (__bch2_uuid_to_fs(c->sb.uuid)) {
 603                 bch_err(c, "filesystem UUID already open");
 604                 return -EINVAL;
 605         }
 606
 607         ret = bch2_fs_chardev_init(c);
 608         if (ret) {
 609                 bch_err(c, "error creating character device");
 610                 return ret;
 611         }
 612
 613         bch2_fs_debug_init(c);
 614
 615         ret = kobject_add(&c->kobj, NULL, "%pU", c->sb.user_uuid.b) ?:
 616             kobject_add(&c->internal, &c->kobj, "internal") ?:
 617             kobject_add(&c->opts_dir, &c->kobj, "options") ?:
 618             kobject_add(&c->time_stats, &c->kobj, "time_stats") ?:
 619             kobject_add(&c->counters_kobj, &c->kobj, "counters") ?:
 620             bch2_opts_create_sysfs_files(&c->opts_dir);
 621         if (ret) {
 622                 bch_err(c, "error creating sysfs objects");
 623                 return ret;
 624         }
 625
 626         down_write(&c->state_lock);
 627
 628         for_each_member_device(ca, c, i) {
 629                 ret = bch2_dev_sysfs_online(c, ca);
 630                 if (ret) {
 631                         bch_err(c, "error creating sysfs objects");
 632                         percpu_ref_put(&ca->ref);
 633                         goto err;
 634                 }
 635         }
 636
 637         BUG_ON(!list_empty(&c->list));
 638         list_add(&c->list, &bch_fs_list);
 639 err:
 640         up_write(&c->state_lock);
 641         return ret;
 642 }
 643
 644 static struct bch_fs *bch2_fs_alloc(struct bch_sb *sb, struct bch_opts opts)
 645 {
 646         struct bch_sb_field_members *mi;
 647         struct bch_fs *c;
 648         struct printbuf name = PRINTBUF;
 649         unsigned i, iter_size;
 650         int ret = 0;
 651
 652         pr_verbose_init(opts, "");
 653
 654         c = kvpmalloc(sizeof(struct bch_fs), GFP_KERNEL|__GFP_ZERO);
 655         if (!c) {
 656                 c = ERR_PTR(-BCH_ERR_ENOMEM_fs_alloc);
 657                 goto out;
 658         }
 659
 660         __module_get(THIS_MODULE);
 661
 662         closure_init(&c->cl, NULL);
 663
 664         c->kobj.kset = bcachefs_kset;
 665         kobject_init(&c->kobj, &bch2_fs_ktype);
 666         kobject_init(&c->internal, &bch2_fs_internal_ktype);
 667         kobject_init(&c->opts_dir, &bch2_fs_opts_dir_ktype);
 668         kobject_init(&c->time_stats, &bch2_fs_time_stats_ktype);
 669         kobject_init(&c->counters_kobj, &bch2_fs_counters_ktype);
 670
 671         c->minor                = -1;
 672         c->disk_sb.fs_sb        = true;
 673
 674         init_rwsem(&c->state_lock);
 675         mutex_init(&c->sb_lock);
 676         mutex_init(&c->replicas_gc_lock);
 677         mutex_init(&c->btree_root_lock);
 678         INIT_WORK(&c->read_only_work, bch2_fs_read_only_work);
 679
 680         init_rwsem(&c->gc_lock);
 681         mutex_init(&c->gc_gens_lock);
 682
 683         for (i = 0; i < BCH_TIME_STAT_NR; i++)
 684                 bch2_time_stats_init(&c->times[i]);
 685
 686         bch2_fs_copygc_init(c);
 687         bch2_fs_btree_key_cache_init_early(&c->btree_key_cache);
 688         bch2_fs_allocator_background_init(c);
 689         bch2_fs_allocator_foreground_init(c);
 690         bch2_fs_rebalance_init(c);
 691         bch2_fs_quota_init(c);
 692         bch2_fs_ec_init_early(c);
 693         bch2_fs_move_init(c);
 694
 695         INIT_LIST_HEAD(&c->list);
 696
 697         mutex_init(&c->usage_scratch_lock);
 698
 699         mutex_init(&c->bio_bounce_pages_lock);
 700         mutex_init(&c->snapshot_table_lock);
 701
 702         spin_lock_init(&c->btree_write_error_lock);
 703
 704         INIT_WORK(&c->journal_seq_blacklist_gc_work,
 705                   bch2_blacklist_entries_gc);
 706
 707         INIT_LIST_HEAD(&c->journal_iters);
 708
 709         INIT_LIST_HEAD(&c->fsck_errors);
 710         mutex_init(&c->fsck_error_lock);
 711
 712         seqcount_init(&c->gc_pos_lock);
 713
 714         seqcount_init(&c->usage_lock);
 715
 716         sema_init(&c->io_in_flight, 128);
 717
 718         INIT_LIST_HEAD(&c->vfs_inodes_list);
 719         mutex_init(&c->vfs_inodes_lock);
 720
 721         c->copy_gc_enabled              = 1;
 722         c->rebalance.enabled            = 1;
 723         c->promote_whole_extents        = true;
 724
 725         c->journal.flush_write_time     = &c->times[BCH_TIME_journal_flush_write];
 726         c->journal.noflush_write_time   = &c->times[BCH_TIME_journal_noflush_write];
 727         c->journal.blocked_time         = &c->times[BCH_TIME_blocked_journal];
 728         c->journal.flush_seq_time       = &c->times[BCH_TIME_journal_flush_seq];
 729
 730         bch2_fs_btree_cache_init_early(&c->btree_cache);
 731
 732         mutex_init(&c->sectors_available_lock);
 733
 734         ret = percpu_init_rwsem(&c->mark_lock);
 735         if (ret)
 736                 goto err;
 737
 738         mutex_lock(&c->sb_lock);
 739         ret = bch2_sb_to_fs(c, sb);
 740         mutex_unlock(&c->sb_lock);
 741
 742         if (ret)
 743                 goto err;
 744
 745         pr_uuid(&name, c->sb.user_uuid.b);
 746         strscpy(c->name, name.buf, sizeof(c->name));
 747         printbuf_exit(&name);
 748
 749         ret = name.allocation_failure ? -BCH_ERR_ENOMEM_fs_name_alloc : 0;
 750         if (ret)
 751                 goto err;
 752
 753         /* Compat: */
 754         if (sb->version <= bcachefs_metadata_version_inode_v2 &&
 755             !BCH_SB_JOURNAL_FLUSH_DELAY(sb))
 756                 SET_BCH_SB_JOURNAL_FLUSH_DELAY(sb, 1000);
 757
 758         if (sb->version <= bcachefs_metadata_version_inode_v2 &&
 759             !BCH_SB_JOURNAL_RECLAIM_DELAY(sb))
 760                 SET_BCH_SB_JOURNAL_RECLAIM_DELAY(sb, 100);
 761
 762         c->opts = bch2_opts_default;
 763         ret = bch2_opts_from_sb(&c->opts, sb);
 764         if (ret)
 765                 goto err;
 766
 767         bch2_opts_apply(&c->opts, opts);
 768
 769         c->btree_key_cache_btrees |= 1U << BTREE_ID_alloc;
 770         if (c->opts.inodes_use_key_cache)
 771                 c->btree_key_cache_btrees |= 1U << BTREE_ID_inodes;
 772
 773         c->block_bits           = ilog2(block_sectors(c));
 774         c->btree_foreground_merge_threshold = BTREE_FOREGROUND_MERGE_THRESHOLD(c);
 775
 776         if (bch2_fs_init_fault("fs_alloc")) {
 777                 bch_err(c, "fs_alloc fault injected");
 778                 ret = -EFAULT;
 779                 goto err;
 780         }
 781
 782         iter_size = sizeof(struct sort_iter) +
 783                 (btree_blocks(c) + 1) * 2 *
 784                 sizeof(struct sort_iter_set);
 785
 786         c->inode_shard_bits = ilog2(roundup_pow_of_two(num_possible_cpus()));
 787
 788         if (!(c->btree_update_wq = alloc_workqueue("bcachefs",
 789                                 WQ_FREEZABLE|WQ_UNBOUND|WQ_MEM_RECLAIM, 512)) ||
 790             !(c->btree_io_complete_wq = alloc_workqueue("bcachefs_btree_io",
 791                                 WQ_FREEZABLE|WQ_MEM_RECLAIM, 1)) ||
 792             !(c->copygc_wq = alloc_workqueue("bcachefs_copygc",
 793                                 WQ_FREEZABLE|WQ_MEM_RECLAIM|WQ_CPU_INTENSIVE, 1)) ||
 794             !(c->io_complete_wq = alloc_workqueue("bcachefs_io",
 795                                 WQ_FREEZABLE|WQ_HIGHPRI|WQ_MEM_RECLAIM, 1)) ||
 796             !(c->write_ref_wq = alloc_workqueue("bcachefs_write_ref",
 797                                 WQ_FREEZABLE, 0)) ||
 798 #ifndef BCH_WRITE_REF_DEBUG
 799             percpu_ref_init(&c->writes, bch2_writes_disabled,
 800                             PERCPU_REF_INIT_DEAD, GFP_KERNEL) ||
 801 #endif
 802             mempool_init_kmalloc_pool(&c->fill_iter, 1, iter_size) ||
 803             bioset_init(&c->btree_bio, 1,
 804                         max(offsetof(struct btree_read_bio, bio),
 805                             offsetof(struct btree_write_bio, wbio.bio)),
 806                         BIOSET_NEED_BVECS) ||
 807             !(c->pcpu = alloc_percpu(struct bch_fs_pcpu)) ||
 808             !(c->online_reserved = alloc_percpu(u64)) ||
 809             !(c->btree_paths_bufs = alloc_percpu(struct btree_path_buf)) ||
 810             mempool_init_kvpmalloc_pool(&c->btree_bounce_pool, 1,
 811                                         btree_bytes(c)) ||
 812             mempool_init_kmalloc_pool(&c->large_bkey_pool, 1, 2048) ||
 813             !(c->unused_inode_hints = kcalloc(1U << c->inode_shard_bits,
 814                                               sizeof(u64), GFP_KERNEL))) {
 815                 ret = -BCH_ERR_ENOMEM_fs_other_alloc;
 816                 goto err;
 817         }
 818
 819         ret = bch2_fs_counters_init(c) ?:
 820             bch2_io_clock_init(&c->io_clock[READ]) ?:
 821             bch2_io_clock_init(&c->io_clock[WRITE]) ?:
 822             bch2_fs_journal_init(&c->journal) ?:
 823             bch2_fs_replicas_init(c) ?:
 824             bch2_fs_btree_cache_init(c) ?:
 825             bch2_fs_btree_key_cache_init(&c->btree_key_cache) ?:
 826             bch2_fs_btree_iter_init(c) ?:
 827             bch2_fs_btree_interior_update_init(c) ?:
 828             bch2_fs_buckets_waiting_for_journal_init(c) ?:
 829             bch2_fs_btree_write_buffer_init(c) ?:
 830             bch2_fs_subvolumes_init(c) ?:
 831             bch2_fs_io_init(c) ?:
 832             bch2_fs_nocow_locking_init(c) ?:
 833             bch2_fs_encryption_init(c) ?:
 834             bch2_fs_compress_init(c) ?:
 835             bch2_fs_ec_init(c) ?:
 836             bch2_fs_fsio_init(c);
 837         if (ret)
 838                 goto err;
 839
 840         mi = bch2_sb_get_members(c->disk_sb.sb);
 841         for (i = 0; i < c->sb.nr_devices; i++)
 842                 if (bch2_dev_exists(c->disk_sb.sb, mi, i) &&
 843                     bch2_dev_alloc(c, i)) {
 844                         ret = -EEXIST;
 845                         goto err;
 846                 }
 847
 848         bch2_journal_entry_res_resize(&c->journal,
 849                         &c->btree_root_journal_res,
 850                         BTREE_ID_NR * (JSET_KEYS_U64s + BKEY_BTREE_PTR_U64s_MAX));
 851         bch2_dev_usage_journal_reserve(c);
 852         bch2_journal_entry_res_resize(&c->journal,
 853                         &c->clock_journal_res,
 854                         (sizeof(struct jset_entry_clock) / sizeof(u64)) * 2);
 855
 856         mutex_lock(&bch_fs_list_lock);
 857         ret = bch2_fs_online(c);
 858         mutex_unlock(&bch_fs_list_lock);
 859
 860         if (ret)
 861                 goto err;
 862 out:
 863         pr_verbose_init(opts, "ret %i", PTR_ERR_OR_ZERO(c));
 864         return c;
 865 err:
 866         bch2_fs_free(c);
 867         c = ERR_PTR(ret);
 868         goto out;
 869 }
 870
 871 noinline_for_stack
 872 static void print_mount_opts(struct bch_fs *c)
 873 {
 874         enum bch_opt_id i;
 875         struct printbuf p = PRINTBUF;
 876         bool first = true;
 877
 878         prt_printf(&p, "mounted version=%s", bch2_metadata_versions[c->sb.version]);
 879
 880         if (c->opts.read_only) {
 881                 prt_str(&p, " opts=");
 882                 first = false;
 883                 prt_printf(&p, "ro");
 884         }
 885
 886         for (i = 0; i < bch2_opts_nr; i++) {
 887                 const struct bch_option *opt = &bch2_opt_table[i];
 888                 u64 v = bch2_opt_get_by_id(&c->opts, i);
 889
 890                 if (!(opt->flags & OPT_MOUNT))
 891                         continue;
 892
 893                 if (v == bch2_opt_get_by_id(&bch2_opts_default, i))
 894                         continue;
 895
 896                 prt_str(&p, first ? " opts=" : ",");
 897                 first = false;
 898                 bch2_opt_to_text(&p, c, c->disk_sb.sb, opt, v, OPT_SHOW_MOUNT_STYLE);
 899         }
 900
 901         bch_info(c, "%s", p.buf);
 902         printbuf_exit(&p);
 903 }
 904
 905 int bch2_fs_start(struct bch_fs *c)
 906 {
 907         struct bch_sb_field_members *mi;
 908         struct bch_dev *ca;
 909         time64_t now = ktime_get_real_seconds();
 910         unsigned i;
 911         int ret;
 912
 913         down_write(&c->state_lock);
 914
 915         BUG_ON(test_bit(BCH_FS_STARTED, &c->flags));
 916
 917         mutex_lock(&c->sb_lock);
 918
 919         for_each_online_member(ca, c, i)
 920                 bch2_sb_from_fs(c, ca);
 921
 922         mi = bch2_sb_get_members(c->disk_sb.sb);
 923         for_each_online_member(ca, c, i)
 924                 mi->members[ca->dev_idx].last_mount = cpu_to_le64(now);
 925
 926         mutex_unlock(&c->sb_lock);
 927
 928         for_each_rw_member(ca, c, i)
 929                 bch2_dev_allocator_add(c, ca);
 930         bch2_recalc_capacity(c);
 931
 932         for (i = 0; i < BCH_TRANSACTIONS_NR; i++) {
 933                 mutex_lock(&c->btree_transaction_stats[i].lock);
 934                 bch2_time_stats_init(&c->btree_transaction_stats[i].lock_hold_times);
 935                 mutex_unlock(&c->btree_transaction_stats[i].lock);
 936         }
 937
 938         ret = BCH_SB_INITIALIZED(c->disk_sb.sb)
 939                 ? bch2_fs_recovery(c)
 940                 : bch2_fs_initialize(c);
 941         if (ret)
 942                 goto err;
 943
 944         ret = bch2_opts_check_may_set(c);
 945         if (ret)
 946                 goto err;
 947
 948         if (bch2_fs_init_fault("fs_start")) {
 949                 bch_err(c, "fs_start fault injected");
 950                 ret = -EINVAL;
 951                 goto err;
 952         }
 953
 954         set_bit(BCH_FS_STARTED, &c->flags);
 955
 956         if (c->opts.read_only || c->opts.nochanges) {
 957                 bch2_fs_read_only(c);
 958         } else {
 959                 ret = !test_bit(BCH_FS_RW, &c->flags)
 960                         ? bch2_fs_read_write(c)
 961                         : bch2_fs_read_write_late(c);
 962                 if (ret)
 963                         goto err;
 964         }
 965
 966         print_mount_opts(c);
 967         ret = 0;
 968 out:
 969         up_write(&c->state_lock);
 970         return ret;
 971 err:
 972         bch_err(c, "error starting filesystem: %s", bch2_err_str(ret));
 973         goto out;
 974 }
 975
 976 static int bch2_dev_may_add(struct bch_sb *sb, struct bch_fs *c)
 977 {
 978         struct bch_sb_field_members *sb_mi;
 979
 980         sb_mi = bch2_sb_get_members(sb);
 981         if (!sb_mi)
 982                 return -BCH_ERR_member_info_missing;
 983
 984         if (le16_to_cpu(sb->block_size) != block_sectors(c))
 985                 return -BCH_ERR_mismatched_block_size;
 986
 987         if (le16_to_cpu(sb_mi->members[sb->dev_idx].bucket_size) <
 988             BCH_SB_BTREE_NODE_SIZE(c->disk_sb.sb))
 989                 return -BCH_ERR_bucket_size_too_small;
 990
 991         return 0;
 992 }
 993
 994 static int bch2_dev_in_fs(struct bch_sb *fs, struct bch_sb *sb)
 995 {
 996         struct bch_sb *newest =
 997                 le64_to_cpu(fs->seq) > le64_to_cpu(sb->seq) ? fs : sb;
 998         struct bch_sb_field_members *mi = bch2_sb_get_members(newest);
 999
1000         if (!uuid_equal(&fs->uuid, &sb->uuid))
1001                 return -BCH_ERR_device_not_a_member_of_filesystem;
1002
1003         if (!bch2_dev_exists(newest, mi, sb->dev_idx))
1004                 return -BCH_ERR_device_has_been_removed;
1005
1006         if (fs->block_size != sb->block_size)
1007                 return -BCH_ERR_mismatched_block_size;
1008
1009         return 0;
1010 }
1011
1012 /* Device startup/shutdown: */
1013
1014 static void bch2_dev_release(struct kobject *kobj)
1015 {
1016         struct bch_dev *ca = container_of(kobj, struct bch_dev, kobj);
1017
1018         kfree(ca);
1019 }
1020
1021 static void bch2_dev_free(struct bch_dev *ca)
1022 {
1023         cancel_work_sync(&ca->io_error_work);
1024
1025         if (ca->kobj.state_in_sysfs &&
1026             ca->disk_sb.bdev)
1027                 sysfs_remove_link(bdev_kobj(ca->disk_sb.bdev), "bcachefs");
1028
1029         if (ca->kobj.state_in_sysfs)
1030                 kobject_del(&ca->kobj);
1031
1032         bch2_free_super(&ca->disk_sb);
1033         bch2_dev_journal_exit(ca);
1034
1035         free_percpu(ca->io_done);
1036         bioset_exit(&ca->replica_set);
1037         bch2_dev_buckets_free(ca);
1038         free_page((unsigned long) ca->sb_read_scratch);
1039
1040         bch2_time_stats_exit(&ca->io_latency[WRITE]);
1041         bch2_time_stats_exit(&ca->io_latency[READ]);
1042
1043         percpu_ref_exit(&ca->io_ref);
1044         percpu_ref_exit(&ca->ref);
1045         kobject_put(&ca->kobj);
1046 }
1047
1048 static void __bch2_dev_offline(struct bch_fs *c, struct bch_dev *ca)
1049 {
1050
1051         lockdep_assert_held(&c->state_lock);
1052
1053         if (percpu_ref_is_zero(&ca->io_ref))
1054                 return;
1055
1056         __bch2_dev_read_only(c, ca);
1057
1058         reinit_completion(&ca->io_ref_completion);
1059         percpu_ref_kill(&ca->io_ref);
1060         wait_for_completion(&ca->io_ref_completion);
1061
1062         if (ca->kobj.state_in_sysfs) {
1063                 sysfs_remove_link(bdev_kobj(ca->disk_sb.bdev), "bcachefs");
1064                 sysfs_remove_link(&ca->kobj, "block");
1065         }
1066
1067         bch2_free_super(&ca->disk_sb);
1068         bch2_dev_journal_exit(ca);
1069 }
1070
1071 static void bch2_dev_ref_complete(struct percpu_ref *ref)
1072 {
1073         struct bch_dev *ca = container_of(ref, struct bch_dev, ref);
1074
1075         complete(&ca->ref_completion);
1076 }
1077
1078 static void bch2_dev_io_ref_complete(struct percpu_ref *ref)
1079 {
1080         struct bch_dev *ca = container_of(ref, struct bch_dev, io_ref);
1081
1082         complete(&ca->io_ref_completion);
1083 }
1084
1085 static int bch2_dev_sysfs_online(struct bch_fs *c, struct bch_dev *ca)
1086 {
1087         int ret;
1088
1089         if (!c->kobj.state_in_sysfs)
1090                 return 0;
1091
1092         if (!ca->kobj.state_in_sysfs) {
1093                 ret = kobject_add(&ca->kobj, &c->kobj,
1094                                   "dev-%u", ca->dev_idx);
1095                 if (ret)
1096                         return ret;
1097         }
1098
1099         if (ca->disk_sb.bdev) {
1100                 struct kobject *block = bdev_kobj(ca->disk_sb.bdev);
1101
1102                 ret = sysfs_create_link(block, &ca->kobj, "bcachefs");
1103                 if (ret)
1104                         return ret;
1105
1106                 ret = sysfs_create_link(&ca->kobj, block, "block");
1107                 if (ret)
1108                         return ret;
1109         }
1110
1111         return 0;
1112 }
1113
1114 static struct bch_dev *__bch2_dev_alloc(struct bch_fs *c,
1115                                         struct bch_member *member)
1116 {
1117         struct bch_dev *ca;
1118
1119         ca = kzalloc(sizeof(*ca), GFP_KERNEL);
1120         if (!ca)
1121                 return NULL;
1122
1123         kobject_init(&ca->kobj, &bch2_dev_ktype);
1124         init_completion(&ca->ref_completion);
1125         init_completion(&ca->io_ref_completion);
1126
1127         init_rwsem(&ca->bucket_lock);
1128
1129         INIT_WORK(&ca->io_error_work, bch2_io_error_work);
1130
1131         bch2_time_stats_init(&ca->io_latency[READ]);
1132         bch2_time_stats_init(&ca->io_latency[WRITE]);
1133
1134         ca->mi = bch2_mi_to_cpu(member);
1135         ca->uuid = member->uuid;
1136
1137         ca->nr_btree_reserve = DIV_ROUND_UP(BTREE_NODE_RESERVE,
1138                              ca->mi.bucket_size / btree_sectors(c));
1139
1140         if (percpu_ref_init(&ca->ref, bch2_dev_ref_complete,
1141                             0, GFP_KERNEL) ||
1142             percpu_ref_init(&ca->io_ref, bch2_dev_io_ref_complete,
1143                             PERCPU_REF_INIT_DEAD, GFP_KERNEL) ||
1144             !(ca->sb_read_scratch = (void *) __get_free_page(GFP_KERNEL)) ||
1145             bch2_dev_buckets_alloc(c, ca) ||
1146             bioset_init(&ca->replica_set, 4,
1147                         offsetof(struct bch_write_bio, bio), 0) ||
1148             !(ca->io_done       = alloc_percpu(*ca->io_done)))
1149                 goto err;
1150
1151         return ca;
1152 err:
1153         bch2_dev_free(ca);
1154         return NULL;
1155 }
1156
1157 static void bch2_dev_attach(struct bch_fs *c, struct bch_dev *ca,
1158                             unsigned dev_idx)
1159 {
1160         ca->dev_idx = dev_idx;
1161         __set_bit(ca->dev_idx, ca->self.d);
1162         scnprintf(ca->name, sizeof(ca->name), "dev-%u", dev_idx);
1163
1164         ca->fs = c;
1165         rcu_assign_pointer(c->devs[ca->dev_idx], ca);
1166
1167         if (bch2_dev_sysfs_online(c, ca))
1168                 pr_warn("error creating sysfs objects");
1169 }
1170
1171 static int bch2_dev_alloc(struct bch_fs *c, unsigned dev_idx)
1172 {
1173         struct bch_member *member =
1174                 bch2_sb_get_members(c->disk_sb.sb)->members + dev_idx;
1175         struct bch_dev *ca = NULL;
1176         int ret = 0;
1177
1178         pr_verbose_init(c->opts, "");
1179
1180         if (bch2_fs_init_fault("dev_alloc"))
1181                 goto err;
1182
1183         ca = __bch2_dev_alloc(c, member);
1184         if (!ca)
1185                 goto err;
1186
1187         ca->fs = c;
1188
1189         bch2_dev_attach(c, ca, dev_idx);
1190 out:
1191         pr_verbose_init(c->opts, "ret %i", ret);
1192         return ret;
1193 err:
1194         if (ca)
1195                 bch2_dev_free(ca);
1196         ret = -BCH_ERR_ENOMEM_dev_alloc;
1197         goto out;
1198 }
1199
1200 static int __bch2_dev_attach_bdev(struct bch_dev *ca, struct bch_sb_handle *sb)
1201 {
1202         unsigned ret;
1203
1204         if (bch2_dev_is_online(ca)) {
1205                 bch_err(ca, "already have device online in slot %u",
1206                         sb->sb->dev_idx);
1207                 return -BCH_ERR_device_already_online;
1208         }
1209
1210         if (get_capacity(sb->bdev->bd_disk) <
1211             ca->mi.bucket_size * ca->mi.nbuckets) {
1212                 bch_err(ca, "cannot online: device too small");
1213                 return -BCH_ERR_device_size_too_small;
1214         }
1215
1216         BUG_ON(!percpu_ref_is_zero(&ca->io_ref));
1217
1218         ret = bch2_dev_journal_init(ca, sb->sb);
1219         if (ret)
1220                 return ret;
1221
1222         /* Commit: */
1223         ca->disk_sb = *sb;
1224         if (sb->mode & FMODE_EXCL)
1225                 ca->disk_sb.bdev->bd_holder = ca;
1226         memset(sb, 0, sizeof(*sb));
1227
1228         ca->dev = ca->disk_sb.bdev->bd_dev;
1229
1230         percpu_ref_reinit(&ca->io_ref);
1231
1232         return 0;
1233 }
1234
1235 static int bch2_dev_attach_bdev(struct bch_fs *c, struct bch_sb_handle *sb)
1236 {
1237         struct bch_dev *ca;
1238         int ret;
1239
1240         lockdep_assert_held(&c->state_lock);
1241
1242         if (le64_to_cpu(sb->sb->seq) >
1243             le64_to_cpu(c->disk_sb.sb->seq))
1244                 bch2_sb_to_fs(c, sb->sb);
1245
1246         BUG_ON(sb->sb->dev_idx >= c->sb.nr_devices ||
1247                !c->devs[sb->sb->dev_idx]);
1248
1249         ca = bch_dev_locked(c, sb->sb->dev_idx);
1250
1251         ret = __bch2_dev_attach_bdev(ca, sb);
1252         if (ret)
1253                 return ret;
1254
1255         bch2_dev_sysfs_online(c, ca);
1256
1257         if (c->sb.nr_devices == 1)
1258                 snprintf(c->name, sizeof(c->name), "%pg", ca->disk_sb.bdev);
1259         snprintf(ca->name, sizeof(ca->name), "%pg", ca->disk_sb.bdev);
1260
1261         rebalance_wakeup(c);
1262         return 0;
1263 }
1264
1265 /* Device management: */
1266
1267 /*
1268  * Note: this function is also used by the error paths - when a particular
1269  * device sees an error, we call it to determine whether we can just set the
1270  * device RO, or - if this function returns false - we'll set the whole
1271  * filesystem RO:
1272  *
1273  * XXX: maybe we should be more explicit about whether we're changing state
1274  * because we got an error or what have you?
1275  */
1276 bool bch2_dev_state_allowed(struct bch_fs *c, struct bch_dev *ca,
1277                             enum bch_member_state new_state, int flags)
1278 {
1279         struct bch_devs_mask new_online_devs;
1280         struct bch_dev *ca2;
1281         int i, nr_rw = 0, required;
1282
1283         lockdep_assert_held(&c->state_lock);
1284
1285         switch (new_state) {
1286         case BCH_MEMBER_STATE_rw:
1287                 return true;
1288         case BCH_MEMBER_STATE_ro:
1289                 if (ca->mi.state != BCH_MEMBER_STATE_rw)
1290                         return true;
1291
1292                 /* do we have enough devices to write to?  */
1293                 for_each_member_device(ca2, c, i)
1294                         if (ca2 != ca)
1295                                 nr_rw += ca2->mi.state == BCH_MEMBER_STATE_rw;
1296
1297                 required = max(!(flags & BCH_FORCE_IF_METADATA_DEGRADED)
1298                                ? c->opts.metadata_replicas
1299                                : c->opts.metadata_replicas_required,
1300                                !(flags & BCH_FORCE_IF_DATA_DEGRADED)
1301                                ? c->opts.data_replicas
1302                                : c->opts.data_replicas_required);
1303
1304                 return nr_rw >= required;
1305         case BCH_MEMBER_STATE_failed:
1306         case BCH_MEMBER_STATE_spare:
1307                 if (ca->mi.state != BCH_MEMBER_STATE_rw &&
1308                     ca->mi.state != BCH_MEMBER_STATE_ro)
1309                         return true;
1310
1311                 /* do we have enough devices to read from?  */
1312                 new_online_devs = bch2_online_devs(c);
1313                 __clear_bit(ca->dev_idx, new_online_devs.d);
1314
1315                 return bch2_have_enough_devs(c, new_online_devs, flags, false);
1316         default:
1317                 BUG();
1318         }
1319 }
1320
1321 static bool bch2_fs_may_start(struct bch_fs *c)
1322 {
1323         struct bch_sb_field_members *mi;
1324         struct bch_dev *ca;
1325         unsigned i, flags = 0;
1326
1327         if (c->opts.very_degraded)
1328                 flags |= BCH_FORCE_IF_DEGRADED|BCH_FORCE_IF_LOST;
1329
1330         if (c->opts.degraded)
1331                 flags |= BCH_FORCE_IF_DEGRADED;
1332
1333         if (!c->opts.degraded &&
1334             !c->opts.very_degraded) {
1335                 mutex_lock(&c->sb_lock);
1336                 mi = bch2_sb_get_members(c->disk_sb.sb);
1337
1338                 for (i = 0; i < c->disk_sb.sb->nr_devices; i++) {
1339                         if (!bch2_dev_exists(c->disk_sb.sb, mi, i))
1340                                 continue;
1341
1342                         ca = bch_dev_locked(c, i);
1343
1344                         if (!bch2_dev_is_online(ca) &&
1345                             (ca->mi.state == BCH_MEMBER_STATE_rw ||
1346                              ca->mi.state == BCH_MEMBER_STATE_ro)) {
1347                                 mutex_unlock(&c->sb_lock);
1348                                 return false;
1349                         }
1350                 }
1351                 mutex_unlock(&c->sb_lock);
1352         }
1353
1354         return bch2_have_enough_devs(c, bch2_online_devs(c), flags, true);
1355 }
1356
1357 static void __bch2_dev_read_only(struct bch_fs *c, struct bch_dev *ca)
1358 {
1359         /*
1360          * The allocator thread itself allocates btree nodes, so stop it first:
1361          */
1362         bch2_dev_allocator_remove(c, ca);
1363         bch2_dev_journal_stop(&c->journal, ca);
1364 }
1365
1366 static void __bch2_dev_read_write(struct bch_fs *c, struct bch_dev *ca)
1367 {
1368         lockdep_assert_held(&c->state_lock);
1369
1370         BUG_ON(ca->mi.state != BCH_MEMBER_STATE_rw);
1371
1372         bch2_dev_allocator_add(c, ca);
1373         bch2_recalc_capacity(c);
1374 }
1375
1376 int __bch2_dev_set_state(struct bch_fs *c, struct bch_dev *ca,
1377                          enum bch_member_state new_state, int flags)
1378 {
1379         struct bch_sb_field_members *mi;
1380         int ret = 0;
1381
1382         if (ca->mi.state == new_state)
1383                 return 0;
1384
1385         if (!bch2_dev_state_allowed(c, ca, new_state, flags))
1386                 return -BCH_ERR_device_state_not_allowed;
1387
1388         if (new_state != BCH_MEMBER_STATE_rw)
1389                 __bch2_dev_read_only(c, ca);
1390
1391         bch_notice(ca, "%s", bch2_member_states[new_state]);
1392
1393         mutex_lock(&c->sb_lock);
1394         mi = bch2_sb_get_members(c->disk_sb.sb);
1395         SET_BCH_MEMBER_STATE(&mi->members[ca->dev_idx], new_state);
1396         bch2_write_super(c);
1397         mutex_unlock(&c->sb_lock);
1398
1399         if (new_state == BCH_MEMBER_STATE_rw)
1400                 __bch2_dev_read_write(c, ca);
1401
1402         rebalance_wakeup(c);
1403
1404         return ret;
1405 }
1406
1407 int bch2_dev_set_state(struct bch_fs *c, struct bch_dev *ca,
1408                        enum bch_member_state new_state, int flags)
1409 {
1410         int ret;
1411
1412         down_write(&c->state_lock);
1413         ret = __bch2_dev_set_state(c, ca, new_state, flags);
1414         up_write(&c->state_lock);
1415
1416         return ret;
1417 }
1418
1419 /* Device add/removal: */
1420
1421 static int bch2_dev_remove_alloc(struct bch_fs *c, struct bch_dev *ca)
1422 {
1423         struct bpos start       = POS(ca->dev_idx, 0);
1424         struct bpos end         = POS(ca->dev_idx, U64_MAX);
1425         int ret;
1426
1427         /*
1428          * We clear the LRU and need_discard btrees first so that we don't race
1429          * with bch2_do_invalidates() and bch2_do_discards()
1430          */
1431         ret =   bch2_btree_delete_range(c, BTREE_ID_lru, start, end,
1432                                         BTREE_TRIGGER_NORUN, NULL) ?:
1433                 bch2_btree_delete_range(c, BTREE_ID_need_discard, start, end,
1434                                         BTREE_TRIGGER_NORUN, NULL) ?:
1435                 bch2_btree_delete_range(c, BTREE_ID_freespace, start, end,
1436                                         BTREE_TRIGGER_NORUN, NULL) ?:
1437                 bch2_btree_delete_range(c, BTREE_ID_backpointers, start, end,
1438                                         BTREE_TRIGGER_NORUN, NULL) ?:
1439                 bch2_btree_delete_range(c, BTREE_ID_alloc, start, end,
1440                                         BTREE_TRIGGER_NORUN, NULL) ?:
1441                 bch2_btree_delete_range(c, BTREE_ID_bucket_gens, start, end,
1442                                         BTREE_TRIGGER_NORUN, NULL);
1443         if (ret)
1444                 bch_err(c, "error removing dev alloc info: %s", bch2_err_str(ret));
1445
1446         return ret;
1447 }
1448
1449 int bch2_dev_remove(struct bch_fs *c, struct bch_dev *ca, int flags)
1450 {
1451         struct bch_sb_field_members *mi;
1452         unsigned dev_idx = ca->dev_idx, data;
1453         int ret;
1454
1455         down_write(&c->state_lock);
1456
1457         /*
1458          * We consume a reference to ca->ref, regardless of whether we succeed
1459          * or fail:
1460          */
1461         percpu_ref_put(&ca->ref);
1462
1463         if (!bch2_dev_state_allowed(c, ca, BCH_MEMBER_STATE_failed, flags)) {
1464                 bch_err(ca, "Cannot remove without losing data");
1465                 ret = -BCH_ERR_device_state_not_allowed;
1466                 goto err;
1467         }
1468
1469         __bch2_dev_read_only(c, ca);
1470
1471         ret = bch2_dev_data_drop(c, ca->dev_idx, flags);
1472         if (ret) {
1473                 bch_err(ca, "Remove failed: error dropping data: %s", bch2_err_str(ret));
1474                 goto err;
1475         }
1476
1477         ret = bch2_dev_remove_alloc(c, ca);
1478         if (ret) {
1479                 bch_err(ca, "Remove failed, error deleting alloc info");
1480                 goto err;
1481         }
1482
1483         ret = bch2_journal_flush_device_pins(&c->journal, ca->dev_idx);
1484         if (ret) {
1485                 bch_err(ca, "Remove failed: error flushing journal: %s", bch2_err_str(ret));
1486                 goto err;
1487         }
1488
1489         ret = bch2_journal_flush(&c->journal);
1490         if (ret) {
1491                 bch_err(ca, "Remove failed, journal error");
1492                 goto err;
1493         }
1494
1495         ret = bch2_replicas_gc2(c);
1496         if (ret) {
1497                 bch_err(ca, "Remove failed: error from replicas gc: %s", bch2_err_str(ret));
1498                 goto err;
1499         }
1500
1501         data = bch2_dev_has_data(c, ca);
1502         if (data) {
1503                 struct printbuf data_has = PRINTBUF;
1504
1505                 prt_bitflags(&data_has, bch2_data_types, data);
1506                 bch_err(ca, "Remove failed, still has data (%s)", data_has.buf);
1507                 printbuf_exit(&data_has);
1508                 ret = -EBUSY;
1509                 goto err;
1510         }
1511
1512         __bch2_dev_offline(c, ca);
1513
1514         mutex_lock(&c->sb_lock);
1515         rcu_assign_pointer(c->devs[ca->dev_idx], NULL);
1516         mutex_unlock(&c->sb_lock);
1517
1518         percpu_ref_kill(&ca->ref);
1519         wait_for_completion(&ca->ref_completion);
1520
1521         bch2_dev_free(ca);
1522
1523         /*
1524          * Free this device's slot in the bch_member array - all pointers to
1525          * this device must be gone:
1526          */
1527         mutex_lock(&c->sb_lock);
1528         mi = bch2_sb_get_members(c->disk_sb.sb);
1529         memset(&mi->members[dev_idx].uuid, 0, sizeof(mi->members[dev_idx].uuid));
1530
1531         bch2_write_super(c);
1532
1533         mutex_unlock(&c->sb_lock);
1534         up_write(&c->state_lock);
1535
1536         bch2_dev_usage_journal_reserve(c);
1537         return 0;
1538 err:
1539         if (ca->mi.state == BCH_MEMBER_STATE_rw &&
1540             !percpu_ref_is_zero(&ca->io_ref))
1541                 __bch2_dev_read_write(c, ca);
1542         up_write(&c->state_lock);
1543         return ret;
1544 }
1545
1546 /* Add new device to running filesystem: */
1547 int bch2_dev_add(struct bch_fs *c, const char *path)
1548 {
1549         struct bch_opts opts = bch2_opts_empty();
1550         struct bch_sb_handle sb;
1551         struct bch_dev *ca = NULL;
1552         struct bch_sb_field_members *mi;
1553         struct bch_member dev_mi;
1554         unsigned dev_idx, nr_devices, u64s;
1555         struct printbuf errbuf = PRINTBUF;
1556         struct printbuf label = PRINTBUF;
1557         int ret;
1558
1559         ret = bch2_read_super(path, &opts, &sb);
1560         if (ret) {
1561                 bch_err(c, "device add error: error reading super: %s", bch2_err_str(ret));
1562                 goto err;
1563         }
1564
1565         dev_mi = bch2_sb_get_members(sb.sb)->members[sb.sb->dev_idx];
1566
1567         if (BCH_MEMBER_GROUP(&dev_mi)) {
1568                 bch2_disk_path_to_text(&label, sb.sb, BCH_MEMBER_GROUP(&dev_mi) - 1);
1569                 if (label.allocation_failure) {
1570                         ret = -ENOMEM;
1571                         goto err;
1572                 }
1573         }
1574
1575         ret = bch2_dev_may_add(sb.sb, c);
1576         if (ret) {
1577                 bch_err(c, "device add error: %s", bch2_err_str(ret));
1578                 goto err;
1579         }
1580
1581         ca = __bch2_dev_alloc(c, &dev_mi);
1582         if (!ca) {
1583                 bch2_free_super(&sb);
1584                 ret = -ENOMEM;
1585                 goto err;
1586         }
1587
1588         bch2_dev_usage_init(ca);
1589
1590         ret = __bch2_dev_attach_bdev(ca, &sb);
1591         if (ret) {
1592                 bch2_dev_free(ca);
1593                 goto err;
1594         }
1595
1596         ret = bch2_dev_journal_alloc(ca);
1597         if (ret) {
1598                 bch_err(c, "device add error: journal alloc failed");
1599                 goto err;
1600         }
1601
1602         down_write(&c->state_lock);
1603         mutex_lock(&c->sb_lock);
1604
1605         ret = bch2_sb_from_fs(c, ca);
1606         if (ret) {
1607                 bch_err(c, "device add error: new device superblock too small");
1608                 goto err_unlock;
1609         }
1610
1611         mi = bch2_sb_get_members(ca->disk_sb.sb);
1612
1613         if (!bch2_sb_resize_members(&ca->disk_sb,
1614                                 le32_to_cpu(mi->field.u64s) +
1615                                 sizeof(dev_mi) / sizeof(u64))) {
1616                 bch_err(c, "device add error: new device superblock too small");
1617                 ret = -BCH_ERR_ENOSPC_sb_members;
1618                 goto err_unlock;
1619         }
1620
1621         if (dynamic_fault("bcachefs:add:no_slot"))
1622                 goto no_slot;
1623
1624         mi = bch2_sb_get_members(c->disk_sb.sb);
1625         for (dev_idx = 0; dev_idx < BCH_SB_MEMBERS_MAX; dev_idx++)
1626                 if (!bch2_dev_exists(c->disk_sb.sb, mi, dev_idx))
1627                         goto have_slot;
1628 no_slot:
1629         bch_err(c, "device add error: already have maximum number of devices");
1630         ret = -BCH_ERR_ENOSPC_sb_members;
1631         goto err_unlock;
1632
1633 have_slot:
1634         nr_devices = max_t(unsigned, dev_idx + 1, c->sb.nr_devices);
1635         u64s = (sizeof(struct bch_sb_field_members) +
1636                 sizeof(struct bch_member) * nr_devices) / sizeof(u64);
1637
1638         mi = bch2_sb_resize_members(&c->disk_sb, u64s);
1639         if (!mi) {
1640                 bch_err(c, "device add error: no room in superblock for member info");
1641                 ret = -BCH_ERR_ENOSPC_sb_members;
1642                 goto err_unlock;
1643         }
1644
1645         /* success: */
1646
1647         mi->members[dev_idx] = dev_mi;
1648         mi->members[dev_idx].last_mount = cpu_to_le64(ktime_get_real_seconds());
1649         c->disk_sb.sb->nr_devices       = nr_devices;
1650
1651         ca->disk_sb.sb->dev_idx = dev_idx;
1652         bch2_dev_attach(c, ca, dev_idx);
1653
1654         if (BCH_MEMBER_GROUP(&dev_mi)) {
1655                 ret = __bch2_dev_group_set(c, ca, label.buf);
1656                 if (ret) {
1657                         bch_err(c, "device add error: error setting label");
1658                         goto err_unlock;
1659                 }
1660         }
1661
1662         bch2_write_super(c);
1663         mutex_unlock(&c->sb_lock);
1664
1665         bch2_dev_usage_journal_reserve(c);
1666
1667         ret = bch2_trans_mark_dev_sb(c, ca);
1668         if (ret) {
1669                 bch_err(c, "device add error: error marking new superblock: %s", bch2_err_str(ret));
1670                 goto err_late;
1671         }
1672
1673         ret = bch2_fs_freespace_init(c);
1674         if (ret) {
1675                 bch_err(c, "device add error: error initializing free space: %s", bch2_err_str(ret));
1676                 goto err_late;
1677         }
1678
1679         ca->new_fs_bucket_idx = 0;
1680
1681         if (ca->mi.state == BCH_MEMBER_STATE_rw)
1682                 __bch2_dev_read_write(c, ca);
1683
1684         up_write(&c->state_lock);
1685         return 0;
1686
1687 err_unlock:
1688         mutex_unlock(&c->sb_lock);
1689         up_write(&c->state_lock);
1690 err:
1691         if (ca)
1692                 bch2_dev_free(ca);
1693         bch2_free_super(&sb);
1694         printbuf_exit(&label);
1695         printbuf_exit(&errbuf);
1696         return ret;
1697 err_late:
1698         up_write(&c->state_lock);
1699         ca = NULL;
1700         goto err;
1701 }
1702
1703 /* Hot add existing device to running filesystem: */
1704 int bch2_dev_online(struct bch_fs *c, const char *path)
1705 {
1706         struct bch_opts opts = bch2_opts_empty();
1707         struct bch_sb_handle sb = { NULL };
1708         struct bch_sb_field_members *mi;
1709         struct bch_dev *ca;
1710         unsigned dev_idx;
1711         int ret;
1712
1713         down_write(&c->state_lock);
1714
1715         ret = bch2_read_super(path, &opts, &sb);
1716         if (ret) {
1717                 up_write(&c->state_lock);
1718                 return ret;
1719         }
1720
1721         dev_idx = sb.sb->dev_idx;
1722
1723         ret = bch2_dev_in_fs(c->disk_sb.sb, sb.sb);
1724         if (ret) {
1725                 bch_err(c, "error bringing %s online: %s", path, bch2_err_str(ret));
1726                 goto err;
1727         }
1728
1729         ret = bch2_dev_attach_bdev(c, &sb);
1730         if (ret)
1731                 goto err;
1732
1733         ca = bch_dev_locked(c, dev_idx);
1734
1735         ret = bch2_trans_mark_dev_sb(c, ca);
1736         if (ret) {
1737                 bch_err(c, "error bringing %s online: error from bch2_trans_mark_dev_sb: %s",
1738                         path, bch2_err_str(ret));
1739                 goto err;
1740         }
1741
1742         if (ca->mi.state == BCH_MEMBER_STATE_rw)
1743                 __bch2_dev_read_write(c, ca);
1744
1745         mutex_lock(&c->sb_lock);
1746         mi = bch2_sb_get_members(c->disk_sb.sb);
1747
1748         mi->members[ca->dev_idx].last_mount =
1749                 cpu_to_le64(ktime_get_real_seconds());
1750
1751         bch2_write_super(c);
1752         mutex_unlock(&c->sb_lock);
1753
1754         ret = bch2_fs_freespace_init(c);
1755         if (ret)
1756                 bch_err(c, "device add error: error initializing free space: %s", bch2_err_str(ret));
1757
1758         up_write(&c->state_lock);
1759         return 0;
1760 err:
1761         up_write(&c->state_lock);
1762         bch2_free_super(&sb);
1763         return ret;
1764 }
1765
1766 int bch2_dev_offline(struct bch_fs *c, struct bch_dev *ca, int flags)
1767 {
1768         down_write(&c->state_lock);
1769
1770         if (!bch2_dev_is_online(ca)) {
1771                 bch_err(ca, "Already offline");
1772                 up_write(&c->state_lock);
1773                 return 0;
1774         }
1775
1776         if (!bch2_dev_state_allowed(c, ca, BCH_MEMBER_STATE_failed, flags)) {
1777                 bch_err(ca, "Cannot offline required disk");
1778                 up_write(&c->state_lock);
1779                 return -BCH_ERR_device_state_not_allowed;
1780         }
1781
1782         __bch2_dev_offline(c, ca);
1783
1784         up_write(&c->state_lock);
1785         return 0;
1786 }
1787
1788 int bch2_dev_resize(struct bch_fs *c, struct bch_dev *ca, u64 nbuckets)
1789 {
1790         struct bch_member *mi;
1791         int ret = 0;
1792
1793         down_write(&c->state_lock);
1794
1795         if (nbuckets < ca->mi.nbuckets) {
1796                 bch_err(ca, "Cannot shrink yet");
1797                 ret = -EINVAL;
1798                 goto err;
1799         }
1800
1801         if (bch2_dev_is_online(ca) &&
1802             get_capacity(ca->disk_sb.bdev->bd_disk) <
1803             ca->mi.bucket_size * nbuckets) {
1804                 bch_err(ca, "New size larger than device");
1805                 ret = -BCH_ERR_device_size_too_small;
1806                 goto err;
1807         }
1808
1809         ret = bch2_dev_buckets_resize(c, ca, nbuckets);
1810         if (ret) {
1811                 bch_err(ca, "Resize error: %s", bch2_err_str(ret));
1812                 goto err;
1813         }
1814
1815         ret = bch2_trans_mark_dev_sb(c, ca);
1816         if (ret)
1817                 goto err;
1818
1819         mutex_lock(&c->sb_lock);
1820         mi = &bch2_sb_get_members(c->disk_sb.sb)->members[ca->dev_idx];
1821         mi->nbuckets = cpu_to_le64(nbuckets);
1822
1823         bch2_write_super(c);
1824         mutex_unlock(&c->sb_lock);
1825
1826         bch2_recalc_capacity(c);
1827 err:
1828         up_write(&c->state_lock);
1829         return ret;
1830 }
1831
1832 /* return with ref on ca->ref: */
1833 struct bch_dev *bch2_dev_lookup(struct bch_fs *c, const char *name)
1834 {
1835         struct bch_dev *ca;
1836         unsigned i;
1837
1838         rcu_read_lock();
1839         for_each_member_device_rcu(ca, c, i, NULL)
1840                 if (!strcmp(name, ca->name))
1841                         goto found;
1842         ca = ERR_PTR(-BCH_ERR_ENOENT_dev_not_found);
1843 found:
1844         rcu_read_unlock();
1845
1846         return ca;
1847 }
1848
1849 /* Filesystem open: */
1850
1851 struct bch_fs *bch2_fs_open(char * const *devices, unsigned nr_devices,
1852                             struct bch_opts opts)
1853 {
1854         struct bch_sb_handle *sb = NULL;
1855         struct bch_fs *c = NULL;
1856         struct bch_sb_field_members *mi;
1857         unsigned i, best_sb = 0;
1858         struct printbuf errbuf = PRINTBUF;
1859         int ret = 0;
1860
1861         if (!try_module_get(THIS_MODULE))
1862                 return ERR_PTR(-ENODEV);
1863
1864         pr_verbose_init(opts, "");
1865
1866         if (!nr_devices) {
1867                 ret = -EINVAL;
1868                 goto err;
1869         }
1870
1871         sb = kcalloc(nr_devices, sizeof(*sb), GFP_KERNEL);
1872         if (!sb) {
1873                 ret = -ENOMEM;
1874                 goto err;
1875         }
1876
1877         for (i = 0; i < nr_devices; i++) {
1878                 ret = bch2_read_super(devices[i], &opts, &sb[i]);
1879                 if (ret)
1880                         goto err;
1881
1882         }
1883
1884         for (i = 1; i < nr_devices; i++)
1885                 if (le64_to_cpu(sb[i].sb->seq) >
1886                     le64_to_cpu(sb[best_sb].sb->seq))
1887                         best_sb = i;
1888
1889         mi = bch2_sb_get_members(sb[best_sb].sb);
1890
1891         i = 0;
1892         while (i < nr_devices) {
1893                 if (i != best_sb &&
1894                     !bch2_dev_exists(sb[best_sb].sb, mi, sb[i].sb->dev_idx)) {
1895                         pr_info("%pg has been removed, skipping", sb[i].bdev);
1896                         bch2_free_super(&sb[i]);
1897                         array_remove_item(sb, nr_devices, i);
1898                         continue;
1899                 }
1900
1901                 ret = bch2_dev_in_fs(sb[best_sb].sb, sb[i].sb);
1902                 if (ret)
1903                         goto err_print;
1904                 i++;
1905         }
1906
1907         c = bch2_fs_alloc(sb[best_sb].sb, opts);
1908         if (IS_ERR(c)) {
1909                 ret = PTR_ERR(c);
1910                 goto err;
1911         }
1912
1913         down_write(&c->state_lock);
1914         for (i = 0; i < nr_devices; i++) {
1915                 ret = bch2_dev_attach_bdev(c, &sb[i]);
1916                 if (ret) {
1917                         up_write(&c->state_lock);
1918                         goto err;
1919                 }
1920         }
1921         up_write(&c->state_lock);
1922
1923         if (!bch2_fs_may_start(c)) {
1924                 ret = -BCH_ERR_insufficient_devices_to_start;
1925                 goto err_print;
1926         }
1927
1928         if (!c->opts.nostart) {
1929                 ret = bch2_fs_start(c);
1930                 if (ret)
1931                         goto err;
1932         }
1933 out:
1934         kfree(sb);
1935         printbuf_exit(&errbuf);
1936         module_put(THIS_MODULE);
1937         pr_verbose_init(opts, "ret %s (%i)", bch2_err_str(PTR_ERR_OR_ZERO(c)),
1938                         PTR_ERR_OR_ZERO(c));
1939         return c;
1940 err_print:
1941         pr_err("bch_fs_open err opening %s: %s",
1942                devices[0], bch2_err_str(ret));
1943 err:
1944         if (!IS_ERR_OR_NULL(c))
1945                 bch2_fs_stop(c);
1946         if (sb)
1947                 for (i = 0; i < nr_devices; i++)
1948                         bch2_free_super(&sb[i]);
1949         c = ERR_PTR(ret);
1950         goto out;
1951 }
1952
1953 /* Global interfaces/init */
1954
1955 static void bcachefs_exit(void)
1956 {
1957         bch2_debug_exit();
1958         bch2_vfs_exit();
1959         bch2_chardev_exit();
1960         bch2_btree_key_cache_exit();
1961         if (bcachefs_kset)
1962                 kset_unregister(bcachefs_kset);
1963 }
1964
1965 static int __init bcachefs_init(void)
1966 {
1967         bch2_bkey_pack_test();
1968
1969         if (!(bcachefs_kset = kset_create_and_add("bcachefs", NULL, fs_kobj)) ||
1970             bch2_btree_key_cache_init() ||
1971             bch2_chardev_init() ||
1972             bch2_vfs_init() ||
1973             bch2_debug_init())
1974                 goto err;
1975
1976         return 0;
1977 err:
1978         bcachefs_exit();
1979         return -ENOMEM;
1980 }
1981
1982 #define BCH_DEBUG_PARAM(name, description)                      \
1983         bool bch2_##name;                                       \
1984         module_param_named(name, bch2_##name, bool, 0644);      \
1985         MODULE_PARM_DESC(name, description);
1986 BCH_DEBUG_PARAMS()
1987 #undef BCH_DEBUG_PARAM
1988
1989 unsigned bch2_metadata_version = bcachefs_metadata_version_current;
1990 module_param_named(version, bch2_metadata_version, uint, 0400);
1991
1992 module_exit(bcachefs_exit);
1993 module_init(bcachefs_init);