diff options
Diffstat (limited to 'libbcachefs/super.c')
| -rw-r--r-- | libbcachefs/super.c | 1832 |
1 files changed, 1832 insertions, 0 deletions
diff --git a/libbcachefs/super.c b/libbcachefs/super.c new file mode 100644 index 00000000..8aa5cc00 --- /dev/null +++ b/libbcachefs/super.c @@ -0,0 +1,1832 @@ +/* + * bcachefs setup/teardown code, and some metadata io - read a superblock and + * figure out what to do with it. + * + * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com> + * Copyright 2012 Google, Inc. + */ + +#include "bcachefs.h" +#include "alloc.h" +#include "btree_cache.h" +#include "btree_gc.h" +#include "btree_update.h" +#include "btree_io.h" +#include "chardev.h" +#include "checksum.h" +#include "clock.h" +#include "compress.h" +#include "debug.h" +#include "error.h" +#include "fs.h" +#include "fs-gc.h" +#include "inode.h" +#include "io.h" +#include "journal.h" +#include "keylist.h" +#include "move.h" +#include "migrate.h" +#include "movinggc.h" +#include "super.h" +#include "super-io.h" +#include "tier.h" + +#include <linux/backing-dev.h> +#include <linux/blkdev.h> +#include <linux/debugfs.h> +#include <linux/device.h> +#include <linux/genhd.h> +#include <linux/idr.h> +#include <linux/kthread.h> +#include <linux/module.h> +#include <linux/percpu.h> +#include <linux/random.h> +#include <linux/sysfs.h> +#include <crypto/hash.h> + +#include <trace/events/bcachefs.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Kent Overstreet <kent.overstreet@gmail.com>"); + +static const uuid_le invalid_uuid = { + .b = { + 0xa0, 0x3e, 0xf8, 0xed, 0x3e, 0xe1, 0xb8, 0x78, + 0xc8, 0x50, 0xfc, 0x5e, 0xcb, 0x16, 0xcd, 0x99 + } +}; + +static struct kset *bcachefs_kset; +static LIST_HEAD(bch_fs_list); +static DEFINE_MUTEX(bch_fs_list_lock); + +static DECLARE_WAIT_QUEUE_HEAD(bch_read_only_wait); + +static void bch2_dev_free(struct bch_dev *); +static int bch2_dev_alloc(struct bch_fs *, unsigned); +static int bch2_dev_sysfs_online(struct bch_dev *); +static void __bch2_dev_read_only(struct bch_fs *, struct bch_dev *); + +struct bch_fs *bch2_bdev_to_fs(struct block_device *bdev) +{ + struct bch_fs *c; + struct bch_dev *ca; + unsigned i; + + mutex_lock(&bch_fs_list_lock); + rcu_read_lock(); + + list_for_each_entry(c, &bch_fs_list, list) + for_each_member_device_rcu(ca, c, i) + if (ca->disk_sb.bdev == bdev) { + closure_get(&c->cl); + goto found; + } + c = NULL; +found: + rcu_read_unlock(); + mutex_unlock(&bch_fs_list_lock); + + return c; +} + +static struct bch_fs *__bch2_uuid_to_fs(uuid_le uuid) +{ + struct bch_fs *c; + + lockdep_assert_held(&bch_fs_list_lock); + + list_for_each_entry(c, &bch_fs_list, list) + if (!memcmp(&c->disk_sb->uuid, &uuid, sizeof(uuid_le))) + return c; + + return NULL; +} + +struct bch_fs *bch2_uuid_to_fs(uuid_le uuid) +{ + struct bch_fs *c; + + mutex_lock(&bch_fs_list_lock); + c = __bch2_uuid_to_fs(uuid); + if (c) + closure_get(&c->cl); + mutex_unlock(&bch_fs_list_lock); + + return c; +} + +int bch2_congested(struct bch_fs *c, int bdi_bits) +{ + struct backing_dev_info *bdi; + struct bch_dev *ca; + unsigned i; + int ret = 0; + + if (bdi_bits & (1 << WB_sync_congested)) { + /* Reads - check all devices: */ + for_each_readable_member(ca, c, i) { + bdi = blk_get_backing_dev_info(ca->disk_sb.bdev); + + if (bdi_congested(bdi, bdi_bits)) { + ret = 1; + break; + } + } + } else { + /* Writes prefer fastest tier: */ + struct bch_tier *tier = READ_ONCE(c->fastest_tier); + struct dev_group *grp = tier ? &tier->devs : &c->all_devs; + + rcu_read_lock(); + group_for_each_dev(ca, grp, i) { + bdi = blk_get_backing_dev_info(ca->disk_sb.bdev); + + if (bdi_congested(bdi, bdi_bits)) { + ret = 1; + break; + } + } + rcu_read_unlock(); + } + + return ret; +} + +static int bch2_congested_fn(void *data, int bdi_bits) +{ + struct bch_fs *c = data; + + return bch2_congested(c, bdi_bits); +} + +/* Filesystem RO/RW: */ + +/* + * For startup/shutdown of RW stuff, the dependencies are: + * + * - foreground writes depend on copygc and tiering (to free up space) + * + * - copygc and tiering depend on mark and sweep gc (they actually probably + * don't because they either reserve ahead of time or don't block if + * allocations fail, but allocations can require mark and sweep gc to run + * because of generation number wraparound) + * + * - all of the above depends on the allocator threads + * + * - allocator depends on the journal (when it rewrites prios and gens) + */ + +static void __bch2_fs_read_only(struct bch_fs *c) +{ + struct bch_dev *ca; + unsigned i; + + bch2_tiering_stop(c); + + for_each_member_device(ca, c, i) + bch2_moving_gc_stop(ca); + + bch2_gc_thread_stop(c); + + bch2_btree_flush(c); + + for_each_member_device(ca, c, i) + bch2_dev_allocator_stop(ca); + + bch2_fs_journal_stop(&c->journal); +} + +static void bch2_writes_disabled(struct percpu_ref *writes) +{ + struct bch_fs *c = container_of(writes, struct bch_fs, writes); + + set_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags); + wake_up(&bch_read_only_wait); +} + +void bch2_fs_read_only(struct bch_fs *c) +{ + mutex_lock(&c->state_lock); + if (c->state != BCH_FS_STARTING && + c->state != BCH_FS_RW) + goto out; + + if (test_bit(BCH_FS_ERROR, &c->flags)) + goto out; + + /* + * Block new foreground-end write operations from starting - any new + * writes will return -EROFS: + * + * (This is really blocking new _allocations_, writes to previously + * allocated space can still happen until stopping the allocator in + * bch2_dev_allocator_stop()). + */ + percpu_ref_kill(&c->writes); + + del_timer(&c->foreground_write_wakeup); + cancel_delayed_work(&c->pd_controllers_update); + + c->foreground_write_pd.rate.rate = UINT_MAX; + bch2_wake_delayed_writes((unsigned long) c); + + /* + * If we're not doing an emergency shutdown, we want to wait on + * outstanding writes to complete so they don't see spurious errors due + * to shutting down the allocator: + * + * If we are doing an emergency shutdown outstanding writes may + * hang until we shutdown the allocator so we don't want to wait + * on outstanding writes before shutting everything down - but + * we do need to wait on them before returning and signalling + * that going RO is complete: + */ + wait_event(bch_read_only_wait, + test_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags) || + test_bit(BCH_FS_EMERGENCY_RO, &c->flags)); + + __bch2_fs_read_only(c); + + wait_event(bch_read_only_wait, + test_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags)); + + clear_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags); + + if (!bch2_journal_error(&c->journal) && + !test_bit(BCH_FS_ERROR, &c->flags)) { + mutex_lock(&c->sb_lock); + SET_BCH_SB_CLEAN(c->disk_sb, true); + bch2_write_super(c); + mutex_unlock(&c->sb_lock); + } + + c->state = BCH_FS_RO; +out: + mutex_unlock(&c->state_lock); +} + +static void bch2_fs_read_only_work(struct work_struct *work) +{ + struct bch_fs *c = + container_of(work, struct bch_fs, read_only_work); + + bch2_fs_read_only(c); +} + +static void bch2_fs_read_only_async(struct bch_fs *c) +{ + queue_work(system_long_wq, &c->read_only_work); +} + +bool bch2_fs_emergency_read_only(struct bch_fs *c) +{ + bool ret = !test_and_set_bit(BCH_FS_EMERGENCY_RO, &c->flags); + + bch2_fs_read_only_async(c); + bch2_journal_halt(&c->journal); + + wake_up(&bch_read_only_wait); + return ret; +} + +const char *bch2_fs_read_write(struct bch_fs *c) +{ + struct bch_dev *ca; + const char *err = NULL; + unsigned i; + + mutex_lock(&c->state_lock); + if (c->state != BCH_FS_STARTING && + c->state != BCH_FS_RO) + goto out; + + err = "error starting allocator thread"; + for_each_rw_member(ca, c, i) + if (bch2_dev_allocator_start(ca)) { + percpu_ref_put(&ca->io_ref); + goto err; + } + + err = "error starting btree GC thread"; + if (bch2_gc_thread_start(c)) + goto err; + + err = "error starting moving GC thread"; + for_each_rw_member(ca, c, i) + if (bch2_moving_gc_start(ca)) { + percpu_ref_put(&ca->io_ref); + goto err; + } + + err = "error starting tiering thread"; + if (bch2_tiering_start(c)) + goto err; + + schedule_delayed_work(&c->pd_controllers_update, 5 * HZ); + + if (c->state != BCH_FS_STARTING) + percpu_ref_reinit(&c->writes); + + c->state = BCH_FS_RW; + err = NULL; +out: + mutex_unlock(&c->state_lock); + return err; +err: + __bch2_fs_read_only(c); + goto out; +} + +/* Filesystem startup/shutdown: */ + +static void bch2_fs_free(struct bch_fs *c) +{ + bch2_fs_encryption_exit(c); + bch2_fs_btree_exit(c); + bch2_fs_journal_exit(&c->journal); + bch2_io_clock_exit(&c->io_clock[WRITE]); + bch2_io_clock_exit(&c->io_clock[READ]); + bch2_fs_compress_exit(c); + bdi_destroy(&c->bdi); + lg_lock_free(&c->usage_lock); + free_percpu(c->usage_percpu); + mempool_exit(&c->btree_bounce_pool); + mempool_exit(&c->bio_bounce_pages); + bioset_exit(&c->bio_write); + bioset_exit(&c->bio_read_split); + bioset_exit(&c->bio_read); + bioset_exit(&c->btree_read_bio); + mempool_exit(&c->btree_interior_update_pool); + mempool_exit(&c->btree_reserve_pool); + mempool_exit(&c->fill_iter); + percpu_ref_exit(&c->writes); + + if (c->copygc_wq) + destroy_workqueue(c->copygc_wq); + if (c->wq) + destroy_workqueue(c->wq); + + free_pages((unsigned long) c->disk_sb, c->disk_sb_order); + kfree(c); + module_put(THIS_MODULE); +} + +static void bch2_fs_exit(struct bch_fs *c) +{ + unsigned i; + + del_timer_sync(&c->foreground_write_wakeup); + cancel_delayed_work_sync(&c->pd_controllers_update); + cancel_work_sync(&c->read_only_work); + cancel_work_sync(&c->read_retry_work); + + for (i = 0; i < c->sb.nr_devices; i++) + if (c->devs[i]) + bch2_dev_free(c->devs[i]); + + closure_debug_destroy(&c->cl); + kobject_put(&c->kobj); +} + +static void bch2_fs_offline(struct bch_fs *c) +{ + struct bch_dev *ca; + unsigned i; + + mutex_lock(&bch_fs_list_lock); + list_del(&c->list); + mutex_unlock(&bch_fs_list_lock); + + for_each_member_device(ca, c, i) + if (ca->kobj.state_in_sysfs && + ca->disk_sb.bdev) + sysfs_remove_link(&part_to_dev(ca->disk_sb.bdev->bd_part)->kobj, + "bcachefs"); + + if (c->kobj.state_in_sysfs) + kobject_del(&c->kobj); + + bch2_fs_debug_exit(c); + bch2_fs_chardev_exit(c); + + kobject_put(&c->time_stats); + kobject_put(&c->opts_dir); + kobject_put(&c->internal); + + __bch2_fs_read_only(c); +} + +void bch2_fs_release(struct kobject *kobj) +{ + struct bch_fs *c = container_of(kobj, struct bch_fs, kobj); + + bch2_fs_free(c); +} + +void bch2_fs_stop(struct bch_fs *c) +{ + mutex_lock(&c->state_lock); + BUG_ON(c->state == BCH_FS_STOPPING); + c->state = BCH_FS_STOPPING; + mutex_unlock(&c->state_lock); + + bch2_fs_offline(c); + + closure_sync(&c->cl); + + bch2_fs_exit(c); +} + +#define alloc_bucket_pages(gfp, ca) \ + ((void *) __get_free_pages(__GFP_ZERO|gfp, ilog2(bucket_pages(ca)))) + +static struct bch_fs *bch2_fs_alloc(struct bch_sb *sb, struct bch_opts opts) +{ + struct bch_sb_field_members *mi; + struct bch_fs *c; + unsigned i, iter_size, journal_entry_bytes; + + c = kzalloc(sizeof(struct bch_fs), GFP_KERNEL); + if (!c) + return NULL; + + __module_get(THIS_MODULE); + + c->minor = -1; + + mutex_init(&c->state_lock); + mutex_init(&c->sb_lock); + mutex_init(&c->btree_cache_lock); + mutex_init(&c->bucket_lock); + mutex_init(&c->btree_root_lock); + INIT_WORK(&c->read_only_work, bch2_fs_read_only_work); + + init_rwsem(&c->gc_lock); + +#define BCH_TIME_STAT(name, frequency_units, duration_units) \ + spin_lock_init(&c->name##_time.lock); + BCH_TIME_STATS() +#undef BCH_TIME_STAT + + bch2_fs_allocator_init(c); + bch2_fs_tiering_init(c); + + INIT_LIST_HEAD(&c->list); + INIT_LIST_HEAD(&c->btree_cache); + INIT_LIST_HEAD(&c->btree_cache_freeable); + INIT_LIST_HEAD(&c->btree_cache_freed); + + INIT_LIST_HEAD(&c->btree_interior_update_list); + mutex_init(&c->btree_reserve_cache_lock); + mutex_init(&c->btree_interior_update_lock); + + mutex_init(&c->bio_bounce_pages_lock); + bio_list_init(&c->read_retry_list); + spin_lock_init(&c->read_retry_lock); + INIT_WORK(&c->read_retry_work, bch2_read_retry_work); + mutex_init(&c->zlib_workspace_lock); + + seqcount_init(&c->gc_pos_lock); + + c->prio_clock[READ].hand = 1; + c->prio_clock[READ].min_prio = 0; + c->prio_clock[WRITE].hand = 1; + c->prio_clock[WRITE].min_prio = 0; + + init_waitqueue_head(&c->writeback_wait); + c->writeback_pages_max = (256 << 10) / PAGE_SIZE; + + c->copy_gc_enabled = 1; + c->tiering_enabled = 1; + c->tiering_percent = 10; + + c->foreground_target_percent = 20; + + c->journal.write_time = &c->journal_write_time; + c->journal.delay_time = &c->journal_delay_time; + c->journal.blocked_time = &c->journal_blocked_time; + c->journal.flush_seq_time = &c->journal_flush_seq_time; + + mutex_lock(&c->sb_lock); + + if (bch2_sb_to_fs(c, sb)) { + mutex_unlock(&c->sb_lock); + goto err; + } + + mutex_unlock(&c->sb_lock); + + scnprintf(c->name, sizeof(c->name), "%pU", &c->sb.user_uuid); + + bch2_opts_apply(&c->opts, bch2_sb_opts(sb)); + bch2_opts_apply(&c->opts, opts); + + c->opts.nochanges |= c->opts.noreplay; + c->opts.read_only |= c->opts.nochanges; + + c->block_bits = ilog2(c->sb.block_size); + + if (bch2_fs_init_fault("fs_alloc")) + goto err; + + iter_size = (btree_blocks(c) + 1) * 2 * + sizeof(struct btree_node_iter_set); + + journal_entry_bytes = 512U << BCH_SB_JOURNAL_ENTRY_SIZE(sb); + + if (!(c->wq = alloc_workqueue("bcachefs", + WQ_FREEZABLE|WQ_MEM_RECLAIM|WQ_HIGHPRI, 1)) || + !(c->copygc_wq = alloc_workqueue("bcache_copygc", + WQ_FREEZABLE|WQ_MEM_RECLAIM|WQ_HIGHPRI, 1)) || + percpu_ref_init(&c->writes, bch2_writes_disabled, 0, GFP_KERNEL) || + mempool_init_kmalloc_pool(&c->btree_reserve_pool, 1, + sizeof(struct btree_reserve)) || + mempool_init_kmalloc_pool(&c->btree_interior_update_pool, 1, + sizeof(struct btree_interior_update)) || + mempool_init_kmalloc_pool(&c->fill_iter, 1, iter_size) || + bioset_init(&c->btree_read_bio, 1, 0) || + bioset_init(&c->bio_read, 1, offsetof(struct bch_read_bio, bio)) || + bioset_init(&c->bio_read_split, 1, offsetof(struct bch_read_bio, bio)) || + bioset_init(&c->bio_write, 1, offsetof(struct bch_write_bio, bio)) || + mempool_init_page_pool(&c->bio_bounce_pages, + max_t(unsigned, + c->sb.btree_node_size, + BCH_ENCODED_EXTENT_MAX) / + PAGE_SECTORS, 0) || + !(c->usage_percpu = alloc_percpu(struct bch_fs_usage)) || + lg_lock_init(&c->usage_lock) || + mempool_init_page_pool(&c->btree_bounce_pool, 1, + ilog2(btree_pages(c))) || + bdi_setup_and_register(&c->bdi, "bcachefs") || + bch2_io_clock_init(&c->io_clock[READ]) || + bch2_io_clock_init(&c->io_clock[WRITE]) || + bch2_fs_journal_init(&c->journal, journal_entry_bytes) || + bch2_fs_btree_init(c) || + bch2_fs_encryption_init(c) || + bch2_fs_compress_init(c) || + bch2_check_set_has_compressed_data(c, c->opts.compression)) + goto err; + + c->bdi.ra_pages = VM_MAX_READAHEAD * 1024 / PAGE_SIZE; + c->bdi.congested_fn = bch2_congested_fn; + c->bdi.congested_data = c; + + mi = bch2_sb_get_members(c->disk_sb); + for (i = 0; i < c->sb.nr_devices; i++) + if (!bch2_is_zero(mi->members[i].uuid.b, sizeof(uuid_le)) && + bch2_dev_alloc(c, i)) + goto err; + + /* + * Now that all allocations have succeeded, init various refcounty + * things that let us shutdown: + */ + closure_init(&c->cl, NULL); + + c->kobj.kset = bcachefs_kset; + kobject_init(&c->kobj, &bch2_fs_ktype); + kobject_init(&c->internal, &bch2_fs_internal_ktype); + kobject_init(&c->opts_dir, &bch2_fs_opts_dir_ktype); + kobject_init(&c->time_stats, &bch2_fs_time_stats_ktype); + return c; +err: + bch2_fs_free(c); + return NULL; +} + +static const char *__bch2_fs_online(struct bch_fs *c) +{ + struct bch_dev *ca; + const char *err = NULL; + unsigned i; + int ret; + + lockdep_assert_held(&bch_fs_list_lock); + + if (!list_empty(&c->list)) + return NULL; + + if (__bch2_uuid_to_fs(c->sb.uuid)) + return "filesystem UUID already open"; + + ret = bch2_fs_chardev_init(c); + if (ret) + return "error creating character device"; + + bch2_fs_debug_init(c); + + if (kobject_add(&c->kobj, NULL, "%pU", c->sb.user_uuid.b) || + kobject_add(&c->internal, &c->kobj, "internal") || + kobject_add(&c->opts_dir, &c->kobj, "options") || + kobject_add(&c->time_stats, &c->kobj, "time_stats")) + return "error creating sysfs objects"; + + mutex_lock(&c->state_lock); + + err = "error creating sysfs objects"; + __for_each_member_device(ca, c, i) + if (bch2_dev_sysfs_online(ca)) + goto err; + + list_add(&c->list, &bch_fs_list); + err = NULL; +err: + mutex_unlock(&c->state_lock); + return err; +} + +static const char *bch2_fs_online(struct bch_fs *c) +{ + const char *err; + + mutex_lock(&bch_fs_list_lock); + err = __bch2_fs_online(c); + mutex_unlock(&bch_fs_list_lock); + + return err; +} + +static const char *__bch2_fs_start(struct bch_fs *c) +{ + const char *err = "cannot allocate memory"; + struct bch_sb_field_members *mi; + struct bch_dev *ca; + unsigned i, id; + time64_t now; + LIST_HEAD(journal); + struct jset *j; + int ret = -EINVAL; + + BUG_ON(c->state != BCH_FS_STARTING); + + mutex_lock(&c->sb_lock); + for_each_online_member(ca, c, i) + bch2_sb_from_fs(c, ca); + mutex_unlock(&c->sb_lock); + + if (BCH_SB_INITIALIZED(c->disk_sb)) { + ret = bch2_journal_read(c, &journal); + if (ret) + goto err; + + j = &list_entry(journal.prev, struct journal_replay, list)->j; + + c->prio_clock[READ].hand = le16_to_cpu(j->read_clock); + c->prio_clock[WRITE].hand = le16_to_cpu(j->write_clock); + + err = "error reading priorities"; + for_each_readable_member(ca, c, i) { + ret = bch2_prio_read(ca); + if (ret) { + percpu_ref_put(&ca->io_ref); + goto err; + } + } + + for (id = 0; id < BTREE_ID_NR; id++) { + unsigned level; + struct bkey_i *k; + + err = "bad btree root"; + k = bch2_journal_find_btree_root(c, j, id, &level); + if (!k && id == BTREE_ID_EXTENTS) + goto err; + if (!k) { + pr_debug("missing btree root: %d", id); + continue; + } + + err = "error reading btree root"; + if (bch2_btree_root_read(c, id, k, level)) + goto err; + } + + bch_verbose(c, "starting mark and sweep:"); + + err = "error in recovery"; + if (bch2_initial_gc(c, &journal)) + goto err; + + if (c->opts.noreplay) + goto recovery_done; + + bch_verbose(c, "mark and sweep done"); + + /* + * bch2_journal_start() can't happen sooner, or btree_gc_finish() + * will give spurious errors about oldest_gen > bucket_gen - + * this is a hack but oh well. + */ + bch2_journal_start(c); + + err = "error starting allocator thread"; + for_each_rw_member(ca, c, i) + if (bch2_dev_allocator_start(ca)) { + percpu_ref_put(&ca->io_ref); + goto err; + } + + bch_verbose(c, "starting journal replay:"); + + err = "journal replay failed"; + ret = bch2_journal_replay(c, &journal); + if (ret) + goto err; + + bch_verbose(c, "journal replay done"); + + if (c->opts.norecovery) + goto recovery_done; + + bch_verbose(c, "starting fsck:"); + err = "error in fsck"; + ret = bch2_fsck(c, !c->opts.nofsck); + if (ret) + goto err; + + bch_verbose(c, "fsck done"); + } else { + struct bch_inode_unpacked inode; + struct bkey_inode_buf packed_inode; + struct closure cl; + + closure_init_stack(&cl); + + bch_notice(c, "initializing new filesystem"); + + bch2_initial_gc(c, NULL); + + err = "unable to allocate journal buckets"; + for_each_rw_member(ca, c, i) + if (bch2_dev_journal_alloc(ca)) { + percpu_ref_put(&ca->io_ref); + goto err; + } + + /* + * journal_res_get() will crash if called before this has + * set up the journal.pin FIFO and journal.cur pointer: + */ + bch2_journal_start(c); + bch2_journal_set_replay_done(&c->journal); + + err = "error starting allocator thread"; + for_each_rw_member(ca, c, i) + if (bch2_dev_allocator_start(ca)) { + percpu_ref_put(&ca->io_ref); + goto err; + } + + err = "cannot allocate new btree root"; + for (id = 0; id < BTREE_ID_NR; id++) + if (bch2_btree_root_alloc(c, id, &cl)) { + closure_sync(&cl); + goto err; + } + + /* Wait for new btree roots to be written: */ + closure_sync(&cl); + + bch2_inode_init(c, &inode, 0, 0, + S_IFDIR|S_IRWXU|S_IRUGO|S_IXUGO, 0); + inode.inum = BCACHE_ROOT_INO; + + bch2_inode_pack(&packed_inode, &inode); + + err = "error creating root directory"; + if (bch2_btree_insert(c, BTREE_ID_INODES, + &packed_inode.inode.k_i, + NULL, NULL, NULL, 0)) + goto err; + + err = "error writing first journal entry"; + if (bch2_journal_meta(&c->journal)) + goto err; + } +recovery_done: + err = "dynamic fault"; + if (bch2_fs_init_fault("fs_start")) + goto err; + + if (c->opts.read_only) { + bch2_fs_read_only(c); + } else { + err = bch2_fs_read_write(c); + if (err) + goto err; + } + + mutex_lock(&c->sb_lock); + mi = bch2_sb_get_members(c->disk_sb); + now = ktime_get_seconds(); + + for_each_member_device(ca, c, i) + mi->members[ca->dev_idx].last_mount = cpu_to_le64(now); + + SET_BCH_SB_INITIALIZED(c->disk_sb, true); + SET_BCH_SB_CLEAN(c->disk_sb, false); + c->disk_sb->version = BCACHE_SB_VERSION_CDEV; + + bch2_write_super(c); + mutex_unlock(&c->sb_lock); + + err = NULL; +out: + bch2_journal_entries_free(&journal); + return err; +err: + switch (ret) { + case BCH_FSCK_ERRORS_NOT_FIXED: + bch_err(c, "filesystem contains errors: please report this to the developers"); + pr_cont("mount with -o fix_errors to repair"); + err = "fsck error"; + break; + case BCH_FSCK_REPAIR_UNIMPLEMENTED: + bch_err(c, "filesystem contains errors: please report this to the developers"); + pr_cont("repair unimplemented: inform the developers so that it can be added"); + err = "fsck error"; + break; + case BCH_FSCK_REPAIR_IMPOSSIBLE: + bch_err(c, "filesystem contains errors, but repair impossible"); + err = "fsck error"; + break; + case BCH_FSCK_UNKNOWN_VERSION: + err = "unknown metadata version";; + break; + case -ENOMEM: + err = "cannot allocate memory"; + break; + case -EIO: + err = "IO error"; + break; + } + + BUG_ON(!err); + set_bit(BCH_FS_ERROR, &c->flags); + goto out; +} + +const char *bch2_fs_start(struct bch_fs *c) +{ + return __bch2_fs_start(c) ?: bch2_fs_online(c); +} + +static const char *bch2_dev_may_add(struct bch_sb *sb, struct bch_fs *c) +{ + struct bch_sb_field_members *sb_mi; + + sb_mi = bch2_sb_get_members(sb); + if (!sb_mi) + return "Invalid superblock: member info area missing"; + + if (le16_to_cpu(sb->block_size) != c->sb.block_size) + return "mismatched block size"; + + if (le16_to_cpu(sb_mi->members[sb->dev_idx].bucket_size) < + BCH_SB_BTREE_NODE_SIZE(c->disk_sb)) + return "new cache bucket size is too small"; + + return NULL; +} + +static const char *bch2_dev_in_fs(struct bch_sb *fs, struct bch_sb *sb) +{ + struct bch_sb *newest = + le64_to_cpu(fs->seq) > le64_to_cpu(sb->seq) ? fs : sb; + struct bch_sb_field_members *mi = bch2_sb_get_members(newest); + + if (uuid_le_cmp(fs->uuid, sb->uuid)) + return "device not a member of filesystem"; + + if (sb->dev_idx >= newest->nr_devices) + return "device has invalid dev_idx"; + + if (bch2_is_zero(mi->members[sb->dev_idx].uuid.b, sizeof(uuid_le))) + return "device has been removed"; + + if (fs->block_size != sb->block_size) + return "mismatched block size"; + + return NULL; +} + +/* Device startup/shutdown: */ + +void bch2_dev_release(struct kobject *kobj) +{ + struct bch_dev *ca = container_of(kobj, struct bch_dev, kobj); + + kfree(ca); +} + +static void bch2_dev_free(struct bch_dev *ca) +{ + unsigned i; + + cancel_work_sync(&ca->io_error_work); + + if (ca->kobj.state_in_sysfs && + ca->disk_sb.bdev) + sysfs_remove_link(&part_to_dev(ca->disk_sb.bdev->bd_part)->kobj, + "bcachefs"); + + if (ca->kobj.state_in_sysfs) + kobject_del(&ca->kobj); + + bch2_free_super(&ca->disk_sb); + bch2_dev_journal_exit(ca); + + free_percpu(ca->sectors_written); + bioset_exit(&ca->replica_set); + free_percpu(ca->usage_percpu); + free_pages((unsigned long) ca->disk_buckets, ilog2(bucket_pages(ca))); + kfree(ca->prio_buckets); + kfree(ca->bio_prio); + vfree(ca->buckets); + vfree(ca->oldest_gens); + free_heap(&ca->heap); + free_fifo(&ca->free_inc); + + for (i = 0; i < RESERVE_NR; i++) + free_fifo(&ca->free[i]); + + percpu_ref_exit(&ca->io_ref); + percpu_ref_exit(&ca->ref); + kobject_put(&ca->kobj); +} + +static void bch2_dev_io_ref_release(struct percpu_ref *ref) +{ + struct bch_dev *ca = container_of(ref, struct bch_dev, io_ref); + + complete(&ca->offline_complete); +} + +static void __bch2_dev_offline(struct bch_dev *ca) +{ + struct bch_fs *c = ca->fs; + + lockdep_assert_held(&c->state_lock); + + __bch2_dev_read_only(ca->fs, ca); + + reinit_completion(&ca->offline_complete); + percpu_ref_kill(&ca->io_ref); + wait_for_completion(&ca->offline_complete); + + if (ca->kobj.state_in_sysfs) { + struct kobject *block = + &part_to_dev(ca->disk_sb.bdev->bd_part)->kobj; + + sysfs_remove_link(block, "bcachefs"); + sysfs_remove_link(&ca->kobj, "block"); + } + + bch2_free_super(&ca->disk_sb); + bch2_dev_journal_exit(ca); +} + +static void bch2_dev_ref_release(struct percpu_ref *ref) +{ + struct bch_dev *ca = container_of(ref, struct bch_dev, ref); + + complete(&ca->stop_complete); +} + +static void bch2_dev_stop(struct bch_dev *ca) +{ + struct bch_fs *c = ca->fs; + + lockdep_assert_held(&c->state_lock); + + BUG_ON(rcu_access_pointer(c->devs[ca->dev_idx]) != ca); + rcu_assign_pointer(c->devs[ca->dev_idx], NULL); + + synchronize_rcu(); + + reinit_completion(&ca->stop_complete); + percpu_ref_kill(&ca->ref); + wait_for_completion(&ca->stop_complete); +} + +static int bch2_dev_sysfs_online(struct bch_dev *ca) +{ + struct bch_fs *c = ca->fs; + int ret; + + if (!c->kobj.state_in_sysfs) + return 0; + + if (!ca->kobj.state_in_sysfs) { + ret = kobject_add(&ca->kobj, &ca->fs->kobj, + "dev-%u", ca->dev_idx); + if (ret) + return ret; + } + + if (ca->disk_sb.bdev) { + struct kobject *block = + &part_to_dev(ca->disk_sb.bdev->bd_part)->kobj; + + ret = sysfs_create_link(block, &ca->kobj, "bcachefs"); + if (ret) + return ret; + ret = sysfs_create_link(&ca->kobj, block, "block"); + if (ret) + return ret; + } + + return 0; +} + +static int bch2_dev_alloc(struct bch_fs *c, unsigned dev_idx) +{ + struct bch_member *member; + size_t reserve_none, movinggc_reserve, free_inc_reserve, total_reserve; + size_t heap_size; + unsigned i; + struct bch_dev *ca; + + if (bch2_fs_init_fault("dev_alloc")) + return -ENOMEM; + + ca = kzalloc(sizeof(*ca), GFP_KERNEL); + if (!ca) + return -ENOMEM; + + kobject_init(&ca->kobj, &bch2_dev_ktype); + init_completion(&ca->stop_complete); + init_completion(&ca->offline_complete); + + spin_lock_init(&ca->self.lock); + ca->self.nr = 1; + rcu_assign_pointer(ca->self.d[0].dev, ca); + ca->dev_idx = dev_idx; + + spin_lock_init(&ca->freelist_lock); + spin_lock_init(&ca->prio_buckets_lock); + mutex_init(&ca->heap_lock); + bch2_dev_moving_gc_init(ca); + + INIT_WORK(&ca->io_error_work, bch2_nonfatal_io_error_work); + + if (bch2_fs_init_fault("dev_alloc")) + goto err; + + member = bch2_sb_get_members(c->disk_sb)->members + dev_idx; + + ca->mi = bch2_mi_to_cpu(member); + ca->uuid = member->uuid; + ca->bucket_bits = ilog2(ca->mi.bucket_size); + scnprintf(ca->name, sizeof(ca->name), "dev-%u", dev_idx); + + /* XXX: tune these */ + movinggc_reserve = max_t(size_t, 16, ca->mi.nbuckets >> 7); + reserve_none = max_t(size_t, 4, ca->mi.nbuckets >> 9); + /* + * free_inc must be smaller than the copygc reserve: if it was bigger, + * one copygc iteration might not make enough buckets available to fill + * up free_inc and allow the allocator to make forward progress + */ + free_inc_reserve = movinggc_reserve / 2; + heap_size = movinggc_reserve * 8; + + if (percpu_ref_init(&ca->ref, bch2_dev_ref_release, + 0, GFP_KERNEL) || + percpu_ref_init(&ca->io_ref, bch2_dev_io_ref_release, + PERCPU_REF_INIT_DEAD, GFP_KERNEL) || + !init_fifo(&ca->free[RESERVE_PRIO], prio_buckets(ca), GFP_KERNEL) || + !init_fifo(&ca->free[RESERVE_BTREE], BTREE_NODE_RESERVE, GFP_KERNEL) || + !init_fifo(&ca->free[RESERVE_MOVINGGC], + movinggc_reserve, GFP_KERNEL) || + !init_fifo(&ca->free[RESERVE_NONE], reserve_none, GFP_KERNEL) || + !init_fifo(&ca->free_inc, free_inc_reserve, GFP_KERNEL) || + !init_heap(&ca->heap, heap_size, GFP_KERNEL) || + !(ca->oldest_gens = vzalloc(sizeof(u8) * + ca->mi.nbuckets)) || + !(ca->buckets = vzalloc(sizeof(struct bucket) * + ca->mi.nbuckets)) || + !(ca->prio_buckets = kzalloc(sizeof(u64) * prio_buckets(ca) * + 2, GFP_KERNEL)) || + !(ca->disk_buckets = alloc_bucket_pages(GFP_KERNEL, ca)) || + !(ca->usage_percpu = alloc_percpu(struct bch_dev_usage)) || + !(ca->bio_prio = bio_kmalloc(GFP_NOIO, bucket_pages(ca))) || + bioset_init(&ca->replica_set, 4, + offsetof(struct bch_write_bio, bio)) || + !(ca->sectors_written = alloc_percpu(*ca->sectors_written))) + goto err; + + ca->prio_last_buckets = ca->prio_buckets + prio_buckets(ca); + + total_reserve = ca->free_inc.size; + for (i = 0; i < RESERVE_NR; i++) + total_reserve += ca->free[i].size; + + ca->copygc_write_point.group = &ca->self; + ca->tiering_write_point.group = &ca->self; + + ca->fs = c; + rcu_assign_pointer(c->devs[ca->dev_idx], ca); + + if (bch2_dev_sysfs_online(ca)) + pr_warn("error creating sysfs objects"); + + return 0; +err: + bch2_dev_free(ca); + return -ENOMEM; +} + +static int __bch2_dev_online(struct bch_fs *c, struct bcache_superblock *sb) +{ + struct bch_dev *ca; + int ret; + + lockdep_assert_held(&c->sb_lock); + + if (le64_to_cpu(sb->sb->seq) > + le64_to_cpu(c->disk_sb->seq)) + bch2_sb_to_fs(c, sb->sb); + + BUG_ON(sb->sb->dev_idx >= c->sb.nr_devices || + !c->devs[sb->sb->dev_idx]); + + ca = c->devs[sb->sb->dev_idx]; + if (ca->disk_sb.bdev) { + bch_err(c, "already have device online in slot %u", + sb->sb->dev_idx); + return -EINVAL; + } + + ret = bch2_dev_journal_init(ca, sb->sb); + if (ret) + return ret; + + /* + * Increase journal write timeout if flushes to this device are + * expensive: + */ + if (!blk_queue_nonrot(bdev_get_queue(sb->bdev)) && + journal_flushes_device(ca)) + c->journal.write_delay_ms = + max(c->journal.write_delay_ms, 1000U); + + /* Commit: */ + ca->disk_sb = *sb; + if (sb->mode & FMODE_EXCL) + ca->disk_sb.bdev->bd_holder = ca; + memset(sb, 0, sizeof(*sb)); + + if (c->sb.nr_devices == 1) + bdevname(ca->disk_sb.bdev, c->name); + bdevname(ca->disk_sb.bdev, ca->name); + + if (bch2_dev_sysfs_online(ca)) + pr_warn("error creating sysfs objects"); + + lg_local_lock(&c->usage_lock); + if (!gc_will_visit(c, gc_phase(GC_PHASE_SB_METADATA))) + bch2_mark_dev_metadata(ca->fs, ca); + lg_local_unlock(&c->usage_lock); + + percpu_ref_reinit(&ca->io_ref); + return 0; +} + +/* Device management: */ + +bool bch2_fs_may_start(struct bch_fs *c, int flags) +{ + struct bch_sb_field_members *mi; + unsigned meta_missing = 0; + unsigned data_missing = 0; + bool degraded = false; + unsigned i; + + mutex_lock(&c->sb_lock); + mi = bch2_sb_get_members(c->disk_sb); + + for (i = 0; i < c->disk_sb->nr_devices; i++) + if (!c->devs[i] && + !bch2_is_zero(mi->members[i].uuid.b, sizeof(uuid_le))) { + degraded = true; + if (BCH_MEMBER_HAS_METADATA(&mi->members[i])) + meta_missing++; + if (BCH_MEMBER_HAS_DATA(&mi->members[i])) + data_missing++; + } + mutex_unlock(&c->sb_lock); + + if (degraded && + !(flags & BCH_FORCE_IF_DEGRADED)) + return false; + + if (meta_missing && + !(flags & BCH_FORCE_IF_METADATA_DEGRADED)) + return false; + + if (meta_missing >= BCH_SB_META_REPLICAS_HAVE(c->disk_sb) && + !(flags & BCH_FORCE_IF_METADATA_LOST)) + return false; + + if (data_missing && !(flags & BCH_FORCE_IF_DATA_DEGRADED)) + return false; + + if (data_missing >= BCH_SB_DATA_REPLICAS_HAVE(c->disk_sb) && + !(flags & BCH_FORCE_IF_DATA_LOST)) + return false; + + return true; +} + +bool bch2_dev_state_allowed(struct bch_fs *c, struct bch_dev *ca, + enum bch_member_state new_state, int flags) +{ + lockdep_assert_held(&c->state_lock); + + if (new_state == BCH_MEMBER_STATE_RW) + return true; + + if (ca->mi.has_data && + !(flags & BCH_FORCE_IF_DATA_DEGRADED)) + return false; + + if (ca->mi.has_data && + c->sb.data_replicas_have <= 1 && + !(flags & BCH_FORCE_IF_DATA_LOST)) + return false; + + if (ca->mi.has_metadata && + !(flags & BCH_FORCE_IF_METADATA_DEGRADED)) + return false; + + if (ca->mi.has_metadata && + c->sb.meta_replicas_have <= 1 && + !(flags & BCH_FORCE_IF_METADATA_LOST)) + return false; + + return true; +} + +static void __bch2_dev_read_only(struct bch_fs *c, struct bch_dev *ca) +{ + bch2_moving_gc_stop(ca); + + /* + * This stops new data writes (e.g. to existing open data + * buckets) and then waits for all existing writes to + * complete. + */ + bch2_dev_allocator_stop(ca); + + bch2_dev_group_remove(&c->journal.devs, ca); +} + +static const char *__bch2_dev_read_write(struct bch_fs *c, struct bch_dev *ca) +{ + lockdep_assert_held(&c->state_lock); + + BUG_ON(ca->mi.state != BCH_MEMBER_STATE_RW); + + if (bch2_dev_allocator_start(ca)) + return "error starting allocator thread"; + + if (bch2_moving_gc_start(ca)) + return "error starting moving GC thread"; + + if (bch2_tiering_start(c)) + return "error starting tiering thread"; + + return NULL; +} + +int __bch2_dev_set_state(struct bch_fs *c, struct bch_dev *ca, + enum bch_member_state new_state, int flags) +{ + struct bch_sb_field_members *mi; + + if (ca->mi.state == new_state) + return 0; + + if (!bch2_dev_state_allowed(c, ca, new_state, flags)) + return -EINVAL; + + if (new_state == BCH_MEMBER_STATE_RW) { + if (__bch2_dev_read_write(c, ca)) + return -ENOMEM; + } else { + __bch2_dev_read_only(c, ca); + } + + bch_notice(ca, "%s", bch2_dev_state[new_state]); + + mutex_lock(&c->sb_lock); + mi = bch2_sb_get_members(c->disk_sb); + SET_BCH_MEMBER_STATE(&mi->members[ca->dev_idx], new_state); + bch2_write_super(c); + mutex_unlock(&c->sb_lock); + + return 0; +} + +int bch2_dev_set_state(struct bch_fs *c, struct bch_dev *ca, + enum bch_member_state new_state, int flags) +{ + int ret; + + mutex_lock(&c->state_lock); + ret = __bch2_dev_set_state(c, ca, new_state, flags); + mutex_unlock(&c->state_lock); + + return ret; +} + +/* Device add/removal: */ + +int bch2_dev_remove(struct bch_fs *c, struct bch_dev *ca, int flags) +{ + struct bch_sb_field_members *mi; + unsigned dev_idx = ca->dev_idx; + int ret = -EINVAL; + + mutex_lock(&c->state_lock); + + percpu_ref_put(&ca->ref); /* XXX */ + + if (ca->mi.state == BCH_MEMBER_STATE_RW) { + bch_err(ca, "Cannot remove RW device"); + goto err; + } + + if (!bch2_dev_state_allowed(c, ca, BCH_MEMBER_STATE_FAILED, flags)) { + bch_err(ca, "Cannot remove without losing data"); + goto err; + } + + /* + * XXX: verify that dev_idx is really not in use anymore, anywhere + * + * flag_data_bad() does not check btree pointers + */ + ret = bch2_flag_data_bad(ca); + if (ret) { + bch_err(ca, "Remove failed"); + goto err; + } + + if (ca->mi.has_data || ca->mi.has_metadata) { + bch_err(ca, "Remove failed, still has data"); + goto err; + } + + /* + * Ok, really doing the remove: + * Drop device's prio pointer before removing it from superblock: + */ + spin_lock(&c->journal.lock); + c->journal.prio_buckets[dev_idx] = 0; + spin_unlock(&c->journal.lock); + + bch2_journal_meta(&c->journal); + + __bch2_dev_offline(ca); + bch2_dev_stop(ca); + bch2_dev_free(ca); + + /* + * Free this device's slot in the bch_member array - all pointers to + * this device must be gone: + */ + mutex_lock(&c->sb_lock); + mi = bch2_sb_get_members(c->disk_sb); + memset(&mi->members[dev_idx].uuid, 0, sizeof(mi->members[dev_idx].uuid)); + + bch2_write_super(c); + + mutex_unlock(&c->sb_lock); + mutex_unlock(&c->state_lock); + return 0; +err: + mutex_unlock(&c->state_lock); + return ret; +} + +int bch2_dev_add(struct bch_fs *c, const char *path) +{ + struct bcache_superblock sb; + const char *err; + struct bch_dev *ca = NULL; + struct bch_sb_field_members *mi, *dev_mi; + struct bch_member saved_mi; + unsigned dev_idx, nr_devices, u64s; + int ret = -EINVAL; + + err = bch2_read_super(&sb, bch2_opts_empty(), path); + if (err) + return -EINVAL; + + err = bch2_validate_cache_super(&sb); + if (err) + return -EINVAL; + + err = bch2_dev_may_add(sb.sb, c); + if (err) + return -EINVAL; + + mutex_lock(&c->state_lock); + mutex_lock(&c->sb_lock); + + /* + * Preserve the old cache member information (esp. tier) + * before we start bashing the disk stuff. + */ + dev_mi = bch2_sb_get_members(sb.sb); + saved_mi = dev_mi->members[sb.sb->dev_idx]; + saved_mi.last_mount = cpu_to_le64(ktime_get_seconds()); + + if (dynamic_fault("bcachefs:add:no_slot")) + goto no_slot; + + mi = bch2_sb_get_members(c->disk_sb); + for (dev_idx = 0; dev_idx < BCH_SB_MEMBERS_MAX; dev_idx++) + if (dev_idx >= c->sb.nr_devices || + bch2_is_zero(mi->members[dev_idx].uuid.b, + sizeof(uuid_le))) + goto have_slot; +no_slot: + err = "no slots available in superblock"; + ret = -ENOSPC; + goto err_unlock; + +have_slot: + nr_devices = max_t(unsigned, dev_idx + 1, c->sb.nr_devices); + u64s = (sizeof(struct bch_sb_field_members) + + sizeof(struct bch_member) * nr_devices) / sizeof(u64); + err = "no space in superblock for member info"; + + mi = bch2_fs_sb_resize_members(c, u64s); + if (!mi) + goto err_unlock; + + dev_mi = bch2_sb_resize_members(&sb, u64s); + if (!dev_mi) + goto err_unlock; + + memcpy(dev_mi, mi, u64s * sizeof(u64)); + dev_mi->members[dev_idx] = saved_mi; + + sb.sb->uuid = c->disk_sb->uuid; + sb.sb->dev_idx = dev_idx; + sb.sb->nr_devices = nr_devices; + + /* commit new member info */ + memcpy(mi, dev_mi, u64s * sizeof(u64)); + c->disk_sb->nr_devices = nr_devices; + c->sb.nr_devices = nr_devices; + + if (bch2_dev_alloc(c, dev_idx)) { + err = "cannot allocate memory"; + ret = -ENOMEM; + goto err_unlock; + } + + if (__bch2_dev_online(c, &sb)) { + err = "bch2_dev_online() error"; + ret = -ENOMEM; + goto err_unlock; + } + + bch2_write_super(c); + mutex_unlock(&c->sb_lock); + + ca = c->devs[dev_idx]; + if (ca->mi.state == BCH_MEMBER_STATE_RW) { + err = "journal alloc failed"; + if (bch2_dev_journal_alloc(ca)) + goto err; + + err = __bch2_dev_read_write(c, ca); + if (err) + goto err; + } + + mutex_unlock(&c->state_lock); + return 0; +err_unlock: + mutex_unlock(&c->sb_lock); +err: + mutex_unlock(&c->state_lock); + bch2_free_super(&sb); + + bch_err(c, "Unable to add device: %s", err); + return ret ?: -EINVAL; +} + +int bch2_dev_online(struct bch_fs *c, const char *path) +{ + struct bcache_superblock sb = { 0 }; + struct bch_dev *ca; + unsigned dev_idx; + const char *err; + + mutex_lock(&c->state_lock); + + err = bch2_read_super(&sb, bch2_opts_empty(), path); + if (err) + goto err; + + dev_idx = sb.sb->dev_idx; + + err = bch2_dev_in_fs(c->disk_sb, sb.sb); + if (err) + goto err; + + mutex_lock(&c->sb_lock); + if (__bch2_dev_online(c, &sb)) { + err = "__bch2_dev_online() error"; + mutex_unlock(&c->sb_lock); + goto err; + } + mutex_unlock(&c->sb_lock); + + ca = c->devs[dev_idx]; + if (ca->mi.state == BCH_MEMBER_STATE_RW) { + err = __bch2_dev_read_write(c, ca); + if (err) + goto err; + } + + mutex_unlock(&c->state_lock); + return 0; +err: + mutex_unlock(&c->state_lock); + bch2_free_super(&sb); + bch_err(c, "error bringing %s online: %s", path, err); + return -EINVAL; +} + +int bch2_dev_offline(struct bch_fs *c, struct bch_dev *ca, int flags) +{ + mutex_lock(&c->state_lock); + + if (!bch2_dev_state_allowed(c, ca, BCH_MEMBER_STATE_FAILED, flags)) { + bch_err(ca, "Cannot offline required disk"); + mutex_unlock(&c->state_lock); + return -EINVAL; + } + + __bch2_dev_read_only(c, ca); + __bch2_dev_offline(ca); + + mutex_unlock(&c->state_lock); + return 0; +} + +int bch2_dev_evacuate(struct bch_fs *c, struct bch_dev *ca) +{ + int ret; + + mutex_lock(&c->state_lock); + + if (ca->mi.state == BCH_MEMBER_STATE_RW) { + bch_err(ca, "Cannot migrate data off RW device"); + mutex_unlock(&c->state_lock); + return -EINVAL; + } + + mutex_unlock(&c->state_lock); + + ret = bch2_move_data_off_device(ca); + if (ret) { + bch_err(ca, "Error migrating data: %i", ret); + return ret; + } + + ret = bch2_move_metadata_off_device(ca); + if (ret) { + bch_err(ca, "Error migrating metadata: %i", ret); + return ret; + } + + if (ca->mi.has_data || ca->mi.has_metadata) { + bch_err(ca, "Migrate error: data still present"); + return -EINVAL; + } + + return 0; +} + +/* Filesystem open: */ + +const char *bch2_fs_open(char * const *devices, unsigned nr_devices, + struct bch_opts opts, struct bch_fs **ret) +{ + const char *err; + struct bch_fs *c = NULL; + struct bcache_superblock *sb; + unsigned i, best_sb = 0; + + if (!nr_devices) + return "need at least one device"; + + if (!try_module_get(THIS_MODULE)) + return "module unloading"; + + err = "cannot allocate memory"; + sb = kcalloc(nr_devices, sizeof(*sb), GFP_KERNEL); + if (!sb) + goto err; + + for (i = 0; i < nr_devices; i++) { + err = bch2_read_super(&sb[i], opts, devices[i]); + if (err) + goto err; + + err = "attempting to register backing device"; + if (__SB_IS_BDEV(le64_to_cpu(sb[i].sb->version))) + goto err; + + err = bch2_validate_cache_super(&sb[i]); + if (err) + goto err; + } + + for (i = 1; i < nr_devices; i++) + if (le64_to_cpu(sb[i].sb->seq) > + le64_to_cpu(sb[best_sb].sb->seq)) + best_sb = i; + + for (i = 0; i < nr_devices; i++) { + err = bch2_dev_in_fs(sb[best_sb].sb, sb[i].sb); + if (err) + goto err; + } + + err = "cannot allocate memory"; + c = bch2_fs_alloc(sb[best_sb].sb, opts); + if (!c) + goto err; + + err = "bch2_dev_online() error"; + mutex_lock(&c->sb_lock); + for (i = 0; i < nr_devices; i++) + if (__bch2_dev_online(c, &sb[i])) { + mutex_unlock(&c->sb_lock); + goto err; + } + mutex_unlock(&c->sb_lock); + + err = "insufficient devices"; + if (!bch2_fs_may_start(c, 0)) + goto err; + + if (!c->opts.nostart) { + err = __bch2_fs_start(c); + if (err) + goto err; + } + + err = bch2_fs_online(c); + if (err) + goto err; + + if (ret) + *ret = c; + else + closure_put(&c->cl); + + err = NULL; +out: + kfree(sb); + module_put(THIS_MODULE); + if (err) + c = NULL; + return err; +err: + if (c) + bch2_fs_stop(c); + + for (i = 0; i < nr_devices; i++) + bch2_free_super(&sb[i]); + goto out; +} + +static const char *__bch2_fs_open_incremental(struct bcache_superblock *sb, + struct bch_opts opts) +{ + const char *err; + struct bch_fs *c; + bool allocated_fs = false; + + err = bch2_validate_cache_super(sb); + if (err) + return err; + + mutex_lock(&bch_fs_list_lock); + c = __bch2_uuid_to_fs(sb->sb->uuid); + if (c) { + closure_get(&c->cl); + + err = bch2_dev_in_fs(c->disk_sb, sb->sb); + if (err) + goto err; + } else { + c = bch2_fs_alloc(sb->sb, opts); + err = "cannot allocate memory"; + if (!c) + goto err; + + allocated_fs = true; + } + + err = "bch2_dev_online() error"; + + mutex_lock(&c->sb_lock); + if (__bch2_dev_online(c, sb)) { + mutex_unlock(&c->sb_lock); + goto err; + } + mutex_unlock(&c->sb_lock); + + if (!c->opts.nostart && bch2_fs_may_start(c, 0)) { + err = __bch2_fs_start(c); + if (err) + goto err; + } + + err = __bch2_fs_online(c); + if (err) + goto err; + + closure_put(&c->cl); + mutex_unlock(&bch_fs_list_lock); + + return NULL; +err: + mutex_unlock(&bch_fs_list_lock); + + if (allocated_fs) + bch2_fs_stop(c); + else if (c) + closure_put(&c->cl); + + return err; +} + +const char *bch2_fs_open_incremental(const char *path) +{ + struct bcache_superblock sb; + struct bch_opts opts = bch2_opts_empty(); + const char *err; + + err = bch2_read_super(&sb, opts, path); + if (err) + return err; + + if (!__SB_IS_BDEV(le64_to_cpu(sb.sb->version))) + err = __bch2_fs_open_incremental(&sb, opts); + else + err = "not a bcachefs superblock"; + + bch2_free_super(&sb); + + return err; +} + +/* Global interfaces/init */ + +static void bcachefs_exit(void) +{ + bch2_debug_exit(); + bch2_vfs_exit(); + bch2_chardev_exit(); + if (bcachefs_kset) + kset_unregister(bcachefs_kset); +} + +static int __init bcachefs_init(void) +{ + bch2_bkey_pack_test(); + + if (!(bcachefs_kset = kset_create_and_add("bcachefs", NULL, fs_kobj)) || + bch2_chardev_init() || + bch2_vfs_init() || + bch2_debug_init()) + goto err; + + return 0; +err: + bcachefs_exit(); + return -ENOMEM; +} + +#define BCH_DEBUG_PARAM(name, description) \ + bool bch2_##name; \ + module_param_named(name, bch2_##name, bool, 0644); \ + MODULE_PARM_DESC(name, description); +BCH_DEBUG_PARAMS() +#undef BCH_DEBUG_PARAM + +module_exit(bcachefs_exit); +module_init(bcachefs_init); 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