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