X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libbcachefs%2Frecovery.c;h=3d1bf87ec54468e5eab2a962cc270b4f0d20c654;hb=a2094890a90a2f865e49f94e8448deca7e5852ef;hp=a5651a9cadcfff2104ac8f2060de296f4f35744b;hpb=d13bbb2955f899f10be4ab315ad229d2951fdcda;p=bcachefs-tools-debian

diff --git a/libbcachefs/recovery.c b/libbcachefs/recovery.c
index a5651a9..3d1bf87 100644
--- a/libbcachefs/recovery.c
+++ b/libbcachefs/recovery.c
@@ -1,5 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 
 #include "bcachefs.h"
+#include "bkey_buf.h"
 #include "alloc_background.h"
 #include "btree_gc.h"
 #include "btree_update.h"
@@ -9,161 +11,664 @@
 #include "dirent.h"
 #include "ec.h"
 #include "error.h"
+#include "fs-common.h"
 #include "fsck.h"
 #include "journal_io.h"
+#include "journal_reclaim.h"
 #include "journal_seq_blacklist.h"
+#include "move.h"
 #include "quota.h"
 #include "recovery.h"
 #include "replicas.h"
 #include "super-io.h"
 
+#include <linux/sort.h>
 #include <linux/stat.h>
 
 #define QSTR(n) { { { .len = strlen(n) } }, .name = n }
 
-static struct bkey_i *btree_root_find(struct bch_fs *c,
-				      struct bch_sb_field_clean *clean,
-				      struct jset *j,
-				      enum btree_id id, unsigned *level)
+/* for -o reconstruct_alloc: */
+static void drop_alloc_keys(struct journal_keys *keys)
 {
-	struct bkey_i *k;
-	struct jset_entry *entry, *start, *end;
+	size_t src, dst;
 
-	if (clean) {
-		start = clean->start;
-		end = vstruct_end(&clean->field);
-	} else {
-		start = j->start;
-		end = vstruct_last(j);
+	for (src = 0, dst = 0; src < keys->nr; src++)
+		if (keys->d[src].btree_id != BTREE_ID_alloc)
+			keys->d[dst++] = keys->d[src];
+
+	keys->nr = dst;
+}
+
+/* iterate over keys read from the journal: */
+
+static int __journal_key_cmp(enum btree_id	l_btree_id,
+			     unsigned		l_level,
+			     struct bpos	l_pos,
+			     struct journal_key *r)
+{
+	return (cmp_int(l_btree_id,	r->btree_id) ?:
+		cmp_int(l_level,	r->level) ?:
+		bpos_cmp(l_pos,	r->k->k.p));
+}
+
+static int journal_key_cmp(struct journal_key *l, struct journal_key *r)
+{
+	return (cmp_int(l->btree_id,	r->btree_id) ?:
+		cmp_int(l->level,	r->level) ?:
+		bpos_cmp(l->k->k.p,	r->k->k.p));
+}
+
+static size_t journal_key_search(struct journal_keys *journal_keys,
+				 enum btree_id id, unsigned level,
+				 struct bpos pos)
+{
+	size_t l = 0, r = journal_keys->nr, m;
+
+	while (l < r) {
+		m = l + ((r - l) >> 1);
+		if (__journal_key_cmp(id, level, pos, &journal_keys->d[m]) > 0)
+			l = m + 1;
+		else
+			r = m;
 	}
 
-	for (entry = start; entry < end; entry = vstruct_next(entry))
-		if (entry->type == BCH_JSET_ENTRY_btree_root &&
-		    entry->btree_id == id)
-			goto found;
+	BUG_ON(l < journal_keys->nr &&
+	       __journal_key_cmp(id, level, pos, &journal_keys->d[l]) > 0);
+
+	BUG_ON(l &&
+	       __journal_key_cmp(id, level, pos, &journal_keys->d[l - 1]) <= 0);
+
+	return l;
+}
 
+static void journal_iter_fix(struct bch_fs *c, struct journal_iter *iter, unsigned idx)
+{
+	struct bkey_i *n = iter->keys->d[idx].k;
+	struct btree_and_journal_iter *biter =
+		container_of(iter, struct btree_and_journal_iter, journal);
+
+	if (iter->idx > idx ||
+	    (iter->idx == idx &&
+	     biter->last &&
+	     bpos_cmp(n->k.p, biter->unpacked.p) <= 0))
+		iter->idx++;
+}
+
+int bch2_journal_key_insert(struct bch_fs *c, enum btree_id id,
+			    unsigned level, struct bkey_i *k)
+{
+	struct journal_key n = {
+		.btree_id	= id,
+		.level		= level,
+		.k		= k,
+		.allocated	= true
+	};
+	struct journal_keys *keys = &c->journal_keys;
+	struct journal_iter *iter;
+	unsigned idx = journal_key_search(keys, id, level, k->k.p);
+
+	if (idx < keys->nr &&
+	    journal_key_cmp(&n, &keys->d[idx]) == 0) {
+		if (keys->d[idx].allocated)
+			kfree(keys->d[idx].k);
+		keys->d[idx] = n;
+		return 0;
+	}
+
+	if (keys->nr == keys->size) {
+		struct journal_keys new_keys = {
+			.nr			= keys->nr,
+			.size			= keys->size * 2,
+			.journal_seq_base	= keys->journal_seq_base,
+		};
+
+		new_keys.d = kvmalloc(sizeof(new_keys.d[0]) * new_keys.size, GFP_KERNEL);
+		if (!new_keys.d) {
+			bch_err(c, "%s: error allocating new key array (size %zu)",
+				__func__, new_keys.size);
+			return -ENOMEM;
+		}
+
+		memcpy(new_keys.d, keys->d, sizeof(keys->d[0]) * keys->nr);
+		kvfree(keys->d);
+		*keys = new_keys;
+	}
+
+	array_insert_item(keys->d, keys->nr, idx, n);
+
+	list_for_each_entry(iter, &c->journal_iters, list)
+		journal_iter_fix(c, iter, idx);
+
+	return 0;
+}
+
+int bch2_journal_key_delete(struct bch_fs *c, enum btree_id id,
+			    unsigned level, struct bpos pos)
+{
+	struct bkey_i *whiteout =
+		kmalloc(sizeof(struct bkey), GFP_KERNEL);
+	int ret;
+
+	if (!whiteout) {
+		bch_err(c, "%s: error allocating new key", __func__);
+		return -ENOMEM;
+	}
+
+	bkey_init(&whiteout->k);
+	whiteout->k.p = pos;
+
+	ret = bch2_journal_key_insert(c, id, level, whiteout);
+	if (ret)
+		kfree(whiteout);
+	return ret;
+}
+
+static struct bkey_i *bch2_journal_iter_peek(struct journal_iter *iter)
+{
+	struct journal_key *k = iter->idx - iter->keys->nr
+		? iter->keys->d + iter->idx : NULL;
+
+	if (k &&
+	    k->btree_id	== iter->btree_id &&
+	    k->level	== iter->level)
+		return k->k;
+
+	iter->idx = iter->keys->nr;
 	return NULL;
-found:
-	if (!entry->u64s)
-		return ERR_PTR(-EINVAL);
+}
 
-	k = entry->start;
-	*level = entry->level;
-	return k;
+static void bch2_journal_iter_advance(struct journal_iter *iter)
+{
+	if (iter->idx < iter->keys->nr)
+		iter->idx++;
 }
 
-static int verify_superblock_clean(struct bch_fs *c,
-				   struct bch_sb_field_clean **cleanp,
-				   struct jset *j)
+static void bch2_journal_iter_exit(struct journal_iter *iter)
 {
-	unsigned i;
-	struct bch_sb_field_clean *clean = *cleanp;
+	list_del(&iter->list);
+}
+
+static void bch2_journal_iter_init(struct bch_fs *c,
+				   struct journal_iter *iter,
+				   enum btree_id id, unsigned level,
+				   struct bpos pos)
+{
+	iter->btree_id	= id;
+	iter->level	= level;
+	iter->keys	= &c->journal_keys;
+	iter->idx	= journal_key_search(&c->journal_keys, id, level, pos);
+	list_add(&iter->list, &c->journal_iters);
+}
+
+static struct bkey_s_c bch2_journal_iter_peek_btree(struct btree_and_journal_iter *iter)
+{
+	return bch2_btree_node_iter_peek_unpack(&iter->node_iter,
+						iter->b, &iter->unpacked);
+}
+
+static void bch2_journal_iter_advance_btree(struct btree_and_journal_iter *iter)
+{
+	bch2_btree_node_iter_advance(&iter->node_iter, iter->b);
+}
+
+void bch2_btree_and_journal_iter_advance(struct btree_and_journal_iter *iter)
+{
+	switch (iter->last) {
+	case none:
+		break;
+	case btree:
+		bch2_journal_iter_advance_btree(iter);
+		break;
+	case journal:
+		bch2_journal_iter_advance(&iter->journal);
+		break;
+	}
+
+	iter->last = none;
+}
+
+struct bkey_s_c bch2_btree_and_journal_iter_peek(struct btree_and_journal_iter *iter)
+{
+	struct bkey_s_c ret;
+
+	while (1) {
+		struct bkey_s_c btree_k		=
+			bch2_journal_iter_peek_btree(iter);
+		struct bkey_s_c journal_k	=
+			bkey_i_to_s_c(bch2_journal_iter_peek(&iter->journal));
+
+		if (btree_k.k && journal_k.k) {
+			int cmp = bpos_cmp(btree_k.k->p, journal_k.k->p);
+
+			if (!cmp)
+				bch2_journal_iter_advance_btree(iter);
+
+			iter->last = cmp < 0 ? btree : journal;
+		} else if (btree_k.k) {
+			iter->last = btree;
+		} else if (journal_k.k) {
+			iter->last = journal;
+		} else {
+			iter->last = none;
+			return bkey_s_c_null;
+		}
+
+		ret = iter->last == journal ? journal_k : btree_k;
+
+		if (iter->b &&
+		    bpos_cmp(ret.k->p, iter->b->data->max_key) > 0) {
+			iter->journal.idx = iter->journal.keys->nr;
+			iter->last = none;
+			return bkey_s_c_null;
+		}
+
+		if (!bkey_deleted(ret.k))
+			break;
+
+		bch2_btree_and_journal_iter_advance(iter);
+	}
+
+	return ret;
+}
+
+struct bkey_s_c bch2_btree_and_journal_iter_next(struct btree_and_journal_iter *iter)
+{
+	bch2_btree_and_journal_iter_advance(iter);
+
+	return bch2_btree_and_journal_iter_peek(iter);
+}
+
+void bch2_btree_and_journal_iter_exit(struct btree_and_journal_iter *iter)
+{
+	bch2_journal_iter_exit(&iter->journal);
+}
+
+void bch2_btree_and_journal_iter_init_node_iter(struct btree_and_journal_iter *iter,
+						struct bch_fs *c,
+						struct btree *b)
+{
+	memset(iter, 0, sizeof(*iter));
+
+	iter->b = b;
+	bch2_btree_node_iter_init_from_start(&iter->node_iter, iter->b);
+	bch2_journal_iter_init(c, &iter->journal,
+			       b->c.btree_id, b->c.level, b->data->min_key);
+}
+
+/* Walk btree, overlaying keys from the journal: */
+
+static void btree_and_journal_iter_prefetch(struct bch_fs *c, struct btree *b,
+					   struct btree_and_journal_iter iter)
+{
+	unsigned i = 0, nr = b->c.level > 1 ? 2 : 16;
+	struct bkey_s_c k;
+	struct bkey_buf tmp;
+
+	BUG_ON(!b->c.level);
+
+	bch2_bkey_buf_init(&tmp);
+
+	while (i < nr &&
+	       (k = bch2_btree_and_journal_iter_peek(&iter)).k) {
+		bch2_bkey_buf_reassemble(&tmp, c, k);
+
+		bch2_btree_node_prefetch(c, NULL, tmp.k,
+					b->c.btree_id, b->c.level - 1);
+
+		bch2_btree_and_journal_iter_advance(&iter);
+		i++;
+	}
+
+	bch2_bkey_buf_exit(&tmp, c);
+}
+
+static int bch2_btree_and_journal_walk_recurse(struct bch_fs *c, struct btree *b,
+				struct journal_keys *journal_keys,
+				enum btree_id btree_id,
+				btree_walk_node_fn node_fn,
+				btree_walk_key_fn key_fn)
+{
+	struct btree_and_journal_iter iter;
+	struct bkey_s_c k;
+	struct bkey_buf tmp;
+	struct btree *child;
 	int ret = 0;
 
-	if (!clean || !j)
-		return 0;
+	bch2_bkey_buf_init(&tmp);
+	bch2_btree_and_journal_iter_init_node_iter(&iter, c, b);
 
-	if (mustfix_fsck_err_on(j->seq != clean->journal_seq, c,
-			"superblock journal seq (%llu) doesn't match journal (%llu) after clean shutdown",
-			le64_to_cpu(clean->journal_seq),
-			le64_to_cpu(j->seq))) {
-		kfree(clean);
-		*cleanp = NULL;
+	while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
+		ret = key_fn(c, btree_id, b->c.level, k);
+		if (ret)
+			break;
+
+		if (b->c.level) {
+			bch2_bkey_buf_reassemble(&tmp, c, k);
+
+			bch2_btree_and_journal_iter_advance(&iter);
+
+			child = bch2_btree_node_get_noiter(c, tmp.k,
+						b->c.btree_id, b->c.level - 1,
+						false);
+
+			ret = PTR_ERR_OR_ZERO(child);
+			if (ret)
+				break;
+
+			btree_and_journal_iter_prefetch(c, b, iter);
+
+			ret   = (node_fn ? node_fn(c, b) : 0) ?:
+				bch2_btree_and_journal_walk_recurse(c, child,
+					journal_keys, btree_id, node_fn, key_fn);
+			six_unlock_read(&child->c.lock);
+
+			if (ret)
+				break;
+		} else {
+			bch2_btree_and_journal_iter_advance(&iter);
+		}
+	}
+
+	bch2_btree_and_journal_iter_exit(&iter);
+	bch2_bkey_buf_exit(&tmp, c);
+	return ret;
+}
+
+int bch2_btree_and_journal_walk(struct bch_fs *c, struct journal_keys *journal_keys,
+				enum btree_id btree_id,
+				btree_walk_node_fn node_fn,
+				btree_walk_key_fn key_fn)
+{
+	struct btree *b = c->btree_roots[btree_id].b;
+	int ret = 0;
+
+	if (btree_node_fake(b))
 		return 0;
+
+	six_lock_read(&b->c.lock, NULL, NULL);
+	ret   = (node_fn ? node_fn(c, b) : 0) ?:
+		bch2_btree_and_journal_walk_recurse(c, b, journal_keys, btree_id,
+						    node_fn, key_fn) ?:
+		key_fn(c, btree_id, b->c.level + 1, bkey_i_to_s_c(&b->key));
+	six_unlock_read(&b->c.lock);
+
+	return ret;
+}
+
+/* sort and dedup all keys in the journal: */
+
+void bch2_journal_entries_free(struct list_head *list)
+{
+
+	while (!list_empty(list)) {
+		struct journal_replay *i =
+			list_first_entry(list, struct journal_replay, list);
+		list_del(&i->list);
+		kvpfree(i, offsetof(struct journal_replay, j) +
+			vstruct_bytes(&i->j));
 	}
+}
 
-	mustfix_fsck_err_on(j->read_clock != clean->read_clock, c,
-			"superblock read clock doesn't match journal after clean shutdown");
-	mustfix_fsck_err_on(j->write_clock != clean->write_clock, c,
-			"superblock read clock doesn't match journal after clean shutdown");
+/*
+ * When keys compare equal, oldest compares first:
+ */
+static int journal_sort_key_cmp(const void *_l, const void *_r)
+{
+	const struct journal_key *l = _l;
+	const struct journal_key *r = _r;
+
+	return  cmp_int(l->btree_id,	r->btree_id) ?:
+		cmp_int(l->level,	r->level) ?:
+		bpos_cmp(l->k->k.p, r->k->k.p) ?:
+		cmp_int(l->journal_seq, r->journal_seq) ?:
+		cmp_int(l->journal_offset, r->journal_offset);
+}
 
-	for (i = 0; i < BTREE_ID_NR; i++) {
-		struct bkey_i *k1, *k2;
-		unsigned l1 = 0, l2 = 0;
+void bch2_journal_keys_free(struct journal_keys *keys)
+{
+	struct journal_key *i;
 
-		k1 = btree_root_find(c, clean, NULL, i, &l1);
-		k2 = btree_root_find(c, NULL, j, i, &l2);
+	for (i = keys->d; i < keys->d + keys->nr; i++)
+		if (i->allocated)
+			kfree(i->k);
 
-		if (!k1 && !k2)
+	kvfree(keys->d);
+	keys->d = NULL;
+	keys->nr = 0;
+}
+
+static struct journal_keys journal_keys_sort(struct list_head *journal_entries)
+{
+	struct journal_replay *i;
+	struct jset_entry *entry;
+	struct bkey_i *k, *_n;
+	struct journal_keys keys = { NULL };
+	struct journal_key *src, *dst;
+	size_t nr_keys = 0;
+
+	if (list_empty(journal_entries))
+		return keys;
+
+	list_for_each_entry(i, journal_entries, list) {
+		if (i->ignore)
 			continue;
 
-		mustfix_fsck_err_on(!k1 || !k2 ||
-				    IS_ERR(k1) ||
-				    IS_ERR(k2) ||
-				    k1->k.u64s != k2->k.u64s ||
-				    memcmp(k1, k2, bkey_bytes(k1)) ||
-				    l1 != l2, c,
-			"superblock btree root doesn't match journal after clean shutdown");
+		if (!keys.journal_seq_base)
+			keys.journal_seq_base = le64_to_cpu(i->j.seq);
+
+		for_each_jset_key(k, _n, entry, &i->j)
+			nr_keys++;
 	}
-fsck_err:
+
+	keys.size = roundup_pow_of_two(nr_keys);
+
+	keys.d = kvmalloc(sizeof(keys.d[0]) * keys.size, GFP_KERNEL);
+	if (!keys.d)
+		goto err;
+
+	list_for_each_entry(i, journal_entries, list) {
+		if (i->ignore)
+			continue;
+
+		BUG_ON(le64_to_cpu(i->j.seq) - keys.journal_seq_base > U32_MAX);
+
+		for_each_jset_key(k, _n, entry, &i->j)
+			keys.d[keys.nr++] = (struct journal_key) {
+				.btree_id	= entry->btree_id,
+				.level		= entry->level,
+				.k		= k,
+				.journal_seq	= le64_to_cpu(i->j.seq) -
+					keys.journal_seq_base,
+				.journal_offset	= k->_data - i->j._data,
+			};
+	}
+
+	sort(keys.d, keys.nr, sizeof(keys.d[0]), journal_sort_key_cmp, NULL);
+
+	src = dst = keys.d;
+	while (src < keys.d + keys.nr) {
+		while (src + 1 < keys.d + keys.nr &&
+		       src[0].btree_id	== src[1].btree_id &&
+		       src[0].level	== src[1].level &&
+		       !bpos_cmp(src[0].k->k.p, src[1].k->k.p))
+			src++;
+
+		*dst++ = *src++;
+	}
+
+	keys.nr = dst - keys.d;
+err:
+	return keys;
+}
+
+/* journal replay: */
+
+static void replay_now_at(struct journal *j, u64 seq)
+{
+	BUG_ON(seq < j->replay_journal_seq);
+	BUG_ON(seq > j->replay_journal_seq_end);
+
+	while (j->replay_journal_seq < seq)
+		bch2_journal_pin_put(j, j->replay_journal_seq++);
+}
+
+static int __bch2_journal_replay_key(struct btree_trans *trans,
+				     enum btree_id id, unsigned level,
+				     struct bkey_i *k)
+{
+	struct btree_iter *iter;
+	int ret;
+
+	iter = bch2_trans_get_node_iter(trans, id, k->k.p,
+					BTREE_MAX_DEPTH, level,
+					BTREE_ITER_INTENT);
+
+	/*
+	 * iter->flags & BTREE_ITER_IS_EXTENTS triggers the update path to run
+	 * extent_handle_overwrites() and extent_update_to_keys() - but we don't
+	 * want that here, journal replay is supposed to treat extents like
+	 * regular keys:
+	 */
+	BUG_ON(iter->flags & BTREE_ITER_IS_EXTENTS);
+
+	ret   = bch2_btree_iter_traverse(iter) ?:
+		bch2_trans_update(trans, iter, k, BTREE_TRIGGER_NORUN);
+	bch2_trans_iter_put(trans, iter);
 	return ret;
 }
 
-static int
-verify_journal_entries_not_blacklisted_or_missing(struct bch_fs *c,
-						  struct list_head *journal)
+static int bch2_journal_replay_key(struct bch_fs *c, struct journal_key *k)
 {
-	struct journal_replay *i =
-		list_last_entry(journal, struct journal_replay, list);
-	u64 start_seq	= le64_to_cpu(i->j.last_seq);
-	u64 end_seq	= le64_to_cpu(i->j.seq);
-	u64 seq		= start_seq;
-	int ret = 0;
+	unsigned commit_flags = BTREE_INSERT_NOFAIL|
+		BTREE_INSERT_LAZY_RW;
 
-	list_for_each_entry(i, journal, list) {
-		fsck_err_on(seq != le64_to_cpu(i->j.seq), c,
-			"journal entries %llu-%llu missing! (replaying %llu-%llu)",
-			seq, le64_to_cpu(i->j.seq) - 1,
-			start_seq, end_seq);
+	if (!k->allocated)
+		commit_flags |= BTREE_INSERT_JOURNAL_REPLAY;
 
-		seq = le64_to_cpu(i->j.seq);
+	return bch2_trans_do(c, NULL, NULL, commit_flags,
+			     __bch2_journal_replay_key(&trans, k->btree_id, k->level, k->k));
+}
 
-		fsck_err_on(bch2_journal_seq_is_blacklisted(c, seq, false), c,
-			    "found blacklisted journal entry %llu", seq);
+static int __bch2_alloc_replay_key(struct btree_trans *trans, struct bkey_i *k)
+{
+	struct btree_iter *iter;
+	int ret;
 
-		do {
-			seq++;
-		} while (bch2_journal_seq_is_blacklisted(c, seq, false));
-	}
-fsck_err:
+	iter = bch2_trans_get_iter(trans, BTREE_ID_alloc, k->k.p,
+				   BTREE_ITER_CACHED|
+				   BTREE_ITER_CACHED_NOFILL|
+				   BTREE_ITER_INTENT);
+	ret = bch2_trans_update(trans, iter, k, BTREE_TRIGGER_NORUN);
+	bch2_trans_iter_put(trans, iter);
 	return ret;
 }
 
-static struct bch_sb_field_clean *read_superblock_clean(struct bch_fs *c)
+static int bch2_alloc_replay_key(struct bch_fs *c, struct bkey_i *k)
 {
-	struct bch_sb_field_clean *clean, *sb_clean;
+	return bch2_trans_do(c, NULL, NULL,
+			     BTREE_INSERT_NOFAIL|
+			     BTREE_INSERT_USE_RESERVE|
+			     BTREE_INSERT_LAZY_RW|
+			     BTREE_INSERT_JOURNAL_REPLAY,
+			__bch2_alloc_replay_key(&trans, k));
+}
+
+static int journal_sort_seq_cmp(const void *_l, const void *_r)
+{
+	const struct journal_key *l = _l;
+	const struct journal_key *r = _r;
+
+	return  cmp_int(r->level,	l->level) ?:
+		cmp_int(l->journal_seq, r->journal_seq) ?:
+		cmp_int(l->btree_id,	r->btree_id) ?:
+		bpos_cmp(l->k->k.p,	r->k->k.p);
+}
+
+static int bch2_journal_replay(struct bch_fs *c,
+			       struct journal_keys keys)
+{
+	struct journal *j = &c->journal;
+	struct journal_key *i;
+	u64 seq;
 	int ret;
 
-	mutex_lock(&c->sb_lock);
-	sb_clean = bch2_sb_get_clean(c->disk_sb.sb);
+	sort(keys.d, keys.nr, sizeof(keys.d[0]), journal_sort_seq_cmp, NULL);
 
-	if (fsck_err_on(!sb_clean, c,
-			"superblock marked clean but clean section not present")) {
-		SET_BCH_SB_CLEAN(c->disk_sb.sb, false);
-		c->sb.clean = false;
-		mutex_unlock(&c->sb_lock);
-		return NULL;
+	if (keys.nr)
+		replay_now_at(j, keys.journal_seq_base);
+
+	seq = j->replay_journal_seq;
+
+	/*
+	 * First replay updates to the alloc btree - these will only update the
+	 * btree key cache:
+	 */
+	for_each_journal_key(keys, i) {
+		cond_resched();
+
+		if (!i->level && i->btree_id == BTREE_ID_alloc) {
+			j->replay_journal_seq = keys.journal_seq_base + i->journal_seq;
+			ret = bch2_alloc_replay_key(c, i->k);
+			if (ret)
+				goto err;
+		}
+	}
+
+	/*
+	 * Next replay updates to interior btree nodes:
+	 */
+	for_each_journal_key(keys, i) {
+		cond_resched();
+
+		if (i->level) {
+			j->replay_journal_seq = keys.journal_seq_base + i->journal_seq;
+			ret = bch2_journal_replay_key(c, i);
+			if (ret)
+				goto err;
+		}
 	}
 
-	clean = kmemdup(sb_clean, vstruct_bytes(&sb_clean->field),
-			GFP_KERNEL);
-	if (!clean) {
-		mutex_unlock(&c->sb_lock);
-		return ERR_PTR(-ENOMEM);
-	}
+	/*
+	 * Now that the btree is in a consistent state, we can start journal
+	 * reclaim (which will be flushing entries from the btree key cache back
+	 * to the btree:
+	 */
+	set_bit(BCH_FS_BTREE_INTERIOR_REPLAY_DONE, &c->flags);
+	set_bit(JOURNAL_RECLAIM_STARTED, &j->flags);
+	journal_reclaim_kick(j);
+
+	j->replay_journal_seq = seq;
+
+	/*
+	 * Now replay leaf node updates:
+	 */
+	for_each_journal_key(keys, i) {
+		cond_resched();
+
+		if (i->level || i->btree_id == BTREE_ID_alloc)
+			continue;
 
-	if (le16_to_cpu(c->disk_sb.sb->version) <
-	    bcachefs_metadata_version_bkey_renumber)
-		bch2_sb_clean_renumber(clean, READ);
+		replay_now_at(j, keys.journal_seq_base + i->journal_seq);
 
-	mutex_unlock(&c->sb_lock);
+		ret = bch2_journal_replay_key(c, i);
+		if (ret)
+			goto err;
+	}
 
-	return clean;
-fsck_err:
-	mutex_unlock(&c->sb_lock);
-	return ERR_PTR(ret);
+	replay_now_at(j, j->replay_journal_seq_end);
+	j->replay_journal_seq = 0;
+
+	bch2_journal_set_replay_done(j);
+	bch2_journal_flush_all_pins(j);
+	return bch2_journal_error(j);
+err:
+	bch_err(c, "journal replay: error %d while replaying key at btree %s level %u",
+		ret, bch2_btree_ids[i->btree_id], i->level);
+	return ret;
 }
 
+/* journal replay early: */
+
 static int journal_replay_entry_early(struct bch_fs *c,
 				      struct jset_entry *entry)
 {
@@ -171,7 +676,15 @@ static int journal_replay_entry_early(struct bch_fs *c,
 
 	switch (entry->type) {
 	case BCH_JSET_ENTRY_btree_root: {
-		struct btree_root *r = &c->btree_roots[entry->btree_id];
+		struct btree_root *r;
+
+		if (entry->btree_id >= BTREE_ID_NR) {
+			bch_err(c, "filesystem has unknown btree type %u",
+				entry->btree_id);
+			return -EINVAL;
+		}
+
+		r = &c->btree_roots[entry->btree_id];
 
 		if (entry->u64s) {
 			r->level = entry->level;
@@ -190,13 +703,11 @@ static int journal_replay_entry_early(struct bch_fs *c,
 		switch (entry->btree_id) {
 		case FS_USAGE_RESERVED:
 			if (entry->level < BCH_REPLICAS_MAX)
-				percpu_u64_set(&c->usage[0]->
-					       persistent_reserved[entry->level],
-					       le64_to_cpu(u->v));
+				c->usage_base->persistent_reserved[entry->level] =
+					le64_to_cpu(u->v);
 			break;
 		case FS_USAGE_INODES:
-			percpu_u64_set(&c->usage[0]->nr_inodes,
-				       le64_to_cpu(u->v));
+			c->usage_base->nr_inodes = le64_to_cpu(u->v);
 			break;
 		case FS_USAGE_KEY_VERSION:
 			atomic64_set(&c->key_version,
@@ -209,10 +720,31 @@ static int journal_replay_entry_early(struct bch_fs *c,
 	case BCH_JSET_ENTRY_data_usage: {
 		struct jset_entry_data_usage *u =
 			container_of(entry, struct jset_entry_data_usage, entry);
+
 		ret = bch2_replicas_set_usage(c, &u->r,
 					      le64_to_cpu(u->v));
 		break;
 	}
+	case BCH_JSET_ENTRY_dev_usage: {
+		struct jset_entry_dev_usage *u =
+			container_of(entry, struct jset_entry_dev_usage, entry);
+		struct bch_dev *ca = bch_dev_bkey_exists(c, u->dev);
+		unsigned bytes = jset_u64s(le16_to_cpu(entry->u64s)) * sizeof(u64);
+		unsigned nr_types = (bytes - sizeof(struct jset_entry_dev_usage)) /
+			sizeof(struct jset_entry_dev_usage_type);
+		unsigned i;
+
+		ca->usage_base->buckets_ec		= le64_to_cpu(u->buckets_ec);
+		ca->usage_base->buckets_unavailable	= le64_to_cpu(u->buckets_unavailable);
+
+		for (i = 0; i < nr_types; i++) {
+			ca->usage_base->d[i].buckets	= le64_to_cpu(u->d[i].buckets);
+			ca->usage_base->d[i].sectors	= le64_to_cpu(u->d[i].sectors);
+			ca->usage_base->d[i].fragmented	= le64_to_cpu(u->d[i].fragmented);
+		}
+
+		break;
+	}
 	case BCH_JSET_ENTRY_blacklist: {
 		struct jset_entry_blacklist *bl_entry =
 			container_of(entry, struct jset_entry_blacklist, entry);
@@ -231,6 +763,12 @@ static int journal_replay_entry_early(struct bch_fs *c,
 				le64_to_cpu(bl_entry->end) + 1);
 		break;
 	}
+	case BCH_JSET_ENTRY_clock: {
+		struct jset_entry_clock *clock =
+			container_of(entry, struct jset_entry_clock, entry);
+
+		atomic64_set(&c->io_clock[clock->rw].now, clock->time);
+	}
 	}
 
 	return ret;
@@ -240,13 +778,11 @@ static int journal_replay_early(struct bch_fs *c,
 				struct bch_sb_field_clean *clean,
 				struct list_head *journal)
 {
+	struct journal_replay *i;
 	struct jset_entry *entry;
 	int ret;
 
 	if (clean) {
-		c->bucket_clock[READ].hand = le16_to_cpu(clean->read_clock);
-		c->bucket_clock[WRITE].hand = le16_to_cpu(clean->write_clock);
-
 		for (entry = clean->start;
 		     entry != vstruct_end(&clean->field);
 		     entry = vstruct_next(entry)) {
@@ -255,18 +791,16 @@ static int journal_replay_early(struct bch_fs *c,
 				return ret;
 		}
 	} else {
-		struct journal_replay *i =
-			list_last_entry(journal, struct journal_replay, list);
-
-		c->bucket_clock[READ].hand = le16_to_cpu(i->j.read_clock);
-		c->bucket_clock[WRITE].hand = le16_to_cpu(i->j.write_clock);
+		list_for_each_entry(i, journal, list) {
+			if (i->ignore)
+				continue;
 
-		list_for_each_entry(i, journal, list)
 			vstruct_for_each(&i->j, entry) {
 				ret = journal_replay_entry_early(c, entry);
 				if (ret)
 					return ret;
 			}
+		}
 	}
 
 	bch2_fs_usage_initialize(c);
@@ -274,6 +808,120 @@ static int journal_replay_early(struct bch_fs *c,
 	return 0;
 }
 
+/* sb clean section: */
+
+static struct bkey_i *btree_root_find(struct bch_fs *c,
+				      struct bch_sb_field_clean *clean,
+				      struct jset *j,
+				      enum btree_id id, unsigned *level)
+{
+	struct bkey_i *k;
+	struct jset_entry *entry, *start, *end;
+
+	if (clean) {
+		start = clean->start;
+		end = vstruct_end(&clean->field);
+	} else {
+		start = j->start;
+		end = vstruct_last(j);
+	}
+
+	for (entry = start; entry < end; entry = vstruct_next(entry))
+		if (entry->type == BCH_JSET_ENTRY_btree_root &&
+		    entry->btree_id == id)
+			goto found;
+
+	return NULL;
+found:
+	if (!entry->u64s)
+		return ERR_PTR(-EINVAL);
+
+	k = entry->start;
+	*level = entry->level;
+	return k;
+}
+
+static int verify_superblock_clean(struct bch_fs *c,
+				   struct bch_sb_field_clean **cleanp,
+				   struct jset *j)
+{
+	unsigned i;
+	struct bch_sb_field_clean *clean = *cleanp;
+	int ret = 0;
+
+	if (mustfix_fsck_err_on(j->seq != clean->journal_seq, c,
+			"superblock journal seq (%llu) doesn't match journal (%llu) after clean shutdown",
+			le64_to_cpu(clean->journal_seq),
+			le64_to_cpu(j->seq))) {
+		kfree(clean);
+		*cleanp = NULL;
+		return 0;
+	}
+
+	for (i = 0; i < BTREE_ID_NR; i++) {
+		char buf1[200], buf2[200];
+		struct bkey_i *k1, *k2;
+		unsigned l1 = 0, l2 = 0;
+
+		k1 = btree_root_find(c, clean, NULL, i, &l1);
+		k2 = btree_root_find(c, NULL, j, i, &l2);
+
+		if (!k1 && !k2)
+			continue;
+
+		mustfix_fsck_err_on(!k1 || !k2 ||
+				    IS_ERR(k1) ||
+				    IS_ERR(k2) ||
+				    k1->k.u64s != k2->k.u64s ||
+				    memcmp(k1, k2, bkey_bytes(k1)) ||
+				    l1 != l2, c,
+			"superblock btree root %u doesn't match journal after clean shutdown\n"
+			"sb:      l=%u %s\n"
+			"journal: l=%u %s\n", i,
+			l1, (bch2_bkey_val_to_text(&PBUF(buf1), c, bkey_i_to_s_c(k1)), buf1),
+			l2, (bch2_bkey_val_to_text(&PBUF(buf2), c, bkey_i_to_s_c(k2)), buf2));
+	}
+fsck_err:
+	return ret;
+}
+
+static struct bch_sb_field_clean *read_superblock_clean(struct bch_fs *c)
+{
+	struct bch_sb_field_clean *clean, *sb_clean;
+	int ret;
+
+	mutex_lock(&c->sb_lock);
+	sb_clean = bch2_sb_get_clean(c->disk_sb.sb);
+
+	if (fsck_err_on(!sb_clean, c,
+			"superblock marked clean but clean section not present")) {
+		SET_BCH_SB_CLEAN(c->disk_sb.sb, false);
+		c->sb.clean = false;
+		mutex_unlock(&c->sb_lock);
+		return NULL;
+	}
+
+	clean = kmemdup(sb_clean, vstruct_bytes(&sb_clean->field),
+			GFP_KERNEL);
+	if (!clean) {
+		mutex_unlock(&c->sb_lock);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	ret = bch2_sb_clean_validate(c, clean, READ);
+	if (ret) {
+		mutex_unlock(&c->sb_lock);
+		return ERR_PTR(ret);
+	}
+
+	mutex_unlock(&c->sb_lock);
+
+	return clean;
+fsck_err:
+	mutex_unlock(&c->sb_lock);
+	return ERR_PTR(ret);
+}
+
 static int read_btree_roots(struct bch_fs *c)
 {
 	unsigned i;
@@ -285,29 +933,28 @@ static int read_btree_roots(struct bch_fs *c)
 		if (!r->alive)
 			continue;
 
-		if (i == BTREE_ID_ALLOC &&
-		    test_reconstruct_alloc(c)) {
+		if (i == BTREE_ID_alloc &&
+		    c->opts.reconstruct_alloc) {
 			c->sb.compat &= ~(1ULL << BCH_COMPAT_FEAT_ALLOC_INFO);
 			continue;
 		}
 
-
 		if (r->error) {
-			__fsck_err(c, i == BTREE_ID_ALLOC
+			__fsck_err(c, i == BTREE_ID_alloc
 				   ? FSCK_CAN_IGNORE : 0,
 				   "invalid btree root %s",
 				   bch2_btree_ids[i]);
-			if (i == BTREE_ID_ALLOC)
+			if (i == BTREE_ID_alloc)
 				c->sb.compat &= ~(1ULL << BCH_COMPAT_FEAT_ALLOC_INFO);
 		}
 
 		ret = bch2_btree_root_read(c, i, &r->key, r->level);
 		if (ret) {
-			__fsck_err(c, i == BTREE_ID_ALLOC
+			__fsck_err(c, i == BTREE_ID_alloc
 				   ? FSCK_CAN_IGNORE : 0,
 				   "error reading btree root %s",
 				   bch2_btree_ids[i]);
-			if (i == BTREE_ID_ALLOC)
+			if (i == BTREE_ID_alloc)
 				c->sb.compat &= ~(1ULL << BCH_COMPAT_FEAT_ALLOC_INFO);
 		}
 	}
@@ -319,42 +966,13 @@ fsck_err:
 	return ret;
 }
 
-static bool journal_empty(struct list_head *journal)
-{
-	struct journal_replay *i;
-	struct jset_entry *entry;
-
-	if (list_empty(journal))
-		return true;
-
-	i = list_last_entry(journal, struct journal_replay, list);
-
-	if (i->j.last_seq != i->j.seq)
-		return false;
-
-	list_for_each_entry(i, journal, list) {
-		vstruct_for_each(&i->j, entry) {
-			if (entry->type == BCH_JSET_ENTRY_btree_root ||
-			    entry->type == BCH_JSET_ENTRY_usage ||
-			    entry->type == BCH_JSET_ENTRY_data_usage)
-				continue;
-
-			if (entry->type == BCH_JSET_ENTRY_btree_keys &&
-			    !entry->u64s)
-				continue;
-			return false;
-		}
-	}
-
-	return true;
-}
-
 int bch2_fs_recovery(struct bch_fs *c)
 {
 	const char *err = "cannot allocate memory";
 	struct bch_sb_field_clean *clean = NULL;
-	u64 journal_seq;
-	LIST_HEAD(journal);
+	struct jset *last_journal_entry = NULL;
+	u64 blacklist_seq, journal_seq;
+	bool write_sb = false;
 	int ret;
 
 	if (c->sb.clean)
@@ -367,61 +985,125 @@ int bch2_fs_recovery(struct bch_fs *c)
 		bch_info(c, "recovering from clean shutdown, journal seq %llu",
 			 le64_to_cpu(clean->journal_seq));
 
-	if (!c->replicas.entries) {
+	if (!(c->sb.features & (1ULL << BCH_FEATURE_new_extent_overwrite))) {
+		bch_err(c, "feature new_extent_overwrite not set, filesystem no longer supported");
+		ret = -EINVAL;
+		goto err;
+	}
+
+	if (!c->sb.clean &&
+	    !(c->sb.features & (1ULL << BCH_FEATURE_extents_above_btree_updates))) {
+		bch_err(c, "filesystem needs recovery from older version; run fsck from older bcachefs-tools to fix");
+		ret = -EINVAL;
+		goto err;
+	}
+
+	if (!(c->sb.compat & (1ULL << BCH_COMPAT_FEAT_BFORMAT_OVERFLOW_DONE))) {
+		bch_err(c, "filesystem may have incompatible bkey formats; run fsck from the compat branch to fix");
+		ret = -EINVAL;
+		goto err;
+
+	}
+
+	if (!(c->sb.features & (1ULL << BCH_FEATURE_alloc_v2))) {
+		bch_info(c, "alloc_v2 feature bit not set, fsck required");
+		c->opts.fsck = true;
+		c->opts.fix_errors = FSCK_OPT_YES;
+	}
+
+	if (!c->replicas.entries ||
+	    c->opts.rebuild_replicas) {
 		bch_info(c, "building replicas info");
 		set_bit(BCH_FS_REBUILD_REPLICAS, &c->flags);
 	}
 
-	if (!c->sb.clean || c->opts.fsck) {
-		struct jset *j;
+	ret = bch2_blacklist_table_initialize(c);
+	if (ret) {
+		bch_err(c, "error initializing blacklist table");
+		goto err;
+	}
+
+	if (!c->sb.clean || c->opts.fsck || c->opts.keep_journal) {
+		struct journal_replay *i;
 
-		ret = bch2_journal_read(c, &journal);
+		ret = bch2_journal_read(c, &c->journal_entries,
+					&blacklist_seq, &journal_seq);
 		if (ret)
 			goto err;
 
-		fsck_err_on(c->sb.clean && !journal_empty(&journal), c,
-			    "filesystem marked clean but journal not empty");
+		list_for_each_entry_reverse(i, &c->journal_entries, list)
+			if (!i->ignore) {
+				last_journal_entry = &i->j;
+				break;
+			}
 
-		if (!c->sb.clean && list_empty(&journal)){
-			bch_err(c, "no journal entries found");
-			ret = BCH_FSCK_REPAIR_IMPOSSIBLE;
-			goto err;
+		if (mustfix_fsck_err_on(c->sb.clean &&
+					last_journal_entry &&
+					!journal_entry_empty(last_journal_entry), c,
+				"filesystem marked clean but journal not empty")) {
+			c->sb.compat &= ~(1ULL << BCH_COMPAT_FEAT_ALLOC_INFO);
+			SET_BCH_SB_CLEAN(c->disk_sb.sb, false);
+			c->sb.clean = false;
 		}
 
-		j = &list_last_entry(&journal, struct journal_replay, list)->j;
+		if (!last_journal_entry) {
+			fsck_err_on(!c->sb.clean, c, "no journal entries found");
+			goto use_clean;
+		}
 
-		ret = verify_superblock_clean(c, &clean, j);
-		if (ret)
+		c->journal_keys = journal_keys_sort(&c->journal_entries);
+		if (!c->journal_keys.d) {
+			ret = -ENOMEM;
 			goto err;
+		}
 
-		journal_seq = le64_to_cpu(j->seq) + 1;
+		if (c->sb.clean && last_journal_entry) {
+			ret = verify_superblock_clean(c, &clean,
+						      last_journal_entry);
+			if (ret)
+				goto err;
+		}
 	} else {
-		journal_seq = le64_to_cpu(clean->journal_seq) + 1;
+use_clean:
+		if (!clean) {
+			bch_err(c, "no superblock clean section found");
+			ret = BCH_FSCK_REPAIR_IMPOSSIBLE;
+			goto err;
+
+		}
+		blacklist_seq = journal_seq = le64_to_cpu(clean->journal_seq) + 1;
+	}
+
+	if (c->opts.reconstruct_alloc) {
+		c->sb.compat &= ~(1ULL << BCH_COMPAT_FEAT_ALLOC_INFO);
+		drop_alloc_keys(&c->journal_keys);
 	}
 
-	ret = journal_replay_early(c, clean, &journal);
+	ret = journal_replay_early(c, clean, &c->journal_entries);
 	if (ret)
 		goto err;
 
-	if (!c->sb.clean) {
+	/*
+	 * After an unclean shutdown, skip then next few journal sequence
+	 * numbers as they may have been referenced by btree writes that
+	 * happened before their corresponding journal writes - those btree
+	 * writes need to be ignored, by skipping and blacklisting the next few
+	 * journal sequence numbers:
+	 */
+	if (!c->sb.clean)
+		journal_seq += 8;
+
+	if (blacklist_seq != journal_seq) {
 		ret = bch2_journal_seq_blacklist_add(c,
-				journal_seq,
-				journal_seq + 4);
+					blacklist_seq, journal_seq);
 		if (ret) {
 			bch_err(c, "error creating new journal seq blacklist entry");
 			goto err;
 		}
-
-		journal_seq += 4;
 	}
 
-	ret = bch2_blacklist_table_initialize(c);
-
-	ret = verify_journal_entries_not_blacklisted_or_missing(c, &journal);
-	if (ret)
-		goto err;
-
-	ret = bch2_fs_journal_start(&c->journal, journal_seq, &journal);
+	ret = bch2_fs_journal_start(&c->journal, journal_seq,
+				    &c->journal_entries);
 	if (ret)
 		goto err;
 
@@ -429,13 +1111,16 @@ int bch2_fs_recovery(struct bch_fs *c)
 	if (ret)
 		goto err;
 
+	bch_verbose(c, "starting alloc read");
 	err = "error reading allocation information";
-	ret = bch2_alloc_read(c, &journal);
+	ret = bch2_alloc_read(c, &c->journal_keys);
 	if (ret)
 		goto err;
+	bch_verbose(c, "alloc read done");
 
 	bch_verbose(c, "starting stripes_read");
-	ret = bch2_stripes_read(c, &journal);
+	err = "error reading stripes";
+	ret = bch2_stripes_read(c, &c->journal_keys);
 	if (ret)
 		goto err;
 	bch_verbose(c, "stripes_read done");
@@ -444,15 +1129,18 @@ int bch2_fs_recovery(struct bch_fs *c)
 
 	if (c->opts.fsck ||
 	    !(c->sb.compat & (1ULL << BCH_COMPAT_FEAT_ALLOC_INFO)) ||
+	    !(c->sb.compat & (1ULL << BCH_COMPAT_FEAT_ALLOC_METADATA)) ||
 	    test_bit(BCH_FS_REBUILD_REPLICAS, &c->flags)) {
-		bch_verbose(c, "starting mark and sweep:");
-		err = "error in recovery";
-		ret = bch2_gc(c, &journal, true, false);
+		bch_info(c, "starting mark and sweep");
+		err = "error in mark and sweep";
+		ret = bch2_gc(c, true);
 		if (ret)
 			goto err;
 		bch_verbose(c, "mark and sweep done");
 	}
 
+	bch2_stripes_heap_start(c);
+
 	clear_bit(BCH_FS_REBUILD_REPLICAS, &c->flags);
 	set_bit(BCH_FS_INITIAL_GC_DONE, &c->flags);
 
@@ -463,65 +1151,134 @@ int bch2_fs_recovery(struct bch_fs *c)
 	if (c->sb.encryption_type && !c->sb.clean)
 		atomic64_add(1 << 16, &c->key_version);
 
-	if (c->opts.noreplay)
+	if (c->opts.norecovery)
 		goto out;
 
-	bch_verbose(c, "starting journal replay:");
+	bch_verbose(c, "starting journal replay");
 	err = "journal replay failed";
-	ret = bch2_journal_replay(c, &journal);
+	ret = bch2_journal_replay(c, c->journal_keys);
 	if (ret)
 		goto err;
 	bch_verbose(c, "journal replay done");
 
-	if (c->opts.norecovery)
-		goto out;
+	if (test_bit(BCH_FS_NEED_ALLOC_WRITE, &c->flags) &&
+	    !c->opts.nochanges) {
+		/*
+		 * note that even when filesystem was clean there might be work
+		 * to do here, if we ran gc (because of fsck) which recalculated
+		 * oldest_gen:
+		 */
+		bch_verbose(c, "writing allocation info");
+		err = "error writing out alloc info";
+		ret = bch2_stripes_write(c, BTREE_INSERT_LAZY_RW) ?:
+			bch2_alloc_write(c, BTREE_INSERT_LAZY_RW);
+		if (ret) {
+			bch_err(c, "error writing alloc info");
+			goto err;
+		}
+		bch_verbose(c, "alloc write done");
+	}
 
-	err = "error in fsck";
-	ret = bch2_fsck(c);
-	if (ret)
-		goto err;
+	if (!c->sb.clean) {
+		if (!(c->sb.features & (1 << BCH_FEATURE_atomic_nlink))) {
+			bch_info(c, "checking inode link counts");
+			err = "error in recovery";
+			ret = bch2_fsck_inode_nlink(c);
+			if (ret)
+				goto err;
+			bch_verbose(c, "check inodes done");
+
+		} else {
+			bch_verbose(c, "checking for deleted inodes");
+			err = "error in recovery";
+			ret = bch2_fsck_walk_inodes_only(c);
+			if (ret)
+				goto err;
+			bch_verbose(c, "check inodes done");
+		}
+	}
+
+	if (c->opts.fsck) {
+		bch_info(c, "starting fsck");
+		err = "error in fsck";
+		ret = bch2_fsck_full(c);
+		if (ret)
+			goto err;
+		bch_verbose(c, "fsck done");
+	}
 
 	if (enabled_qtypes(c)) {
-		bch_verbose(c, "reading quotas:");
+		bch_verbose(c, "reading quotas");
 		ret = bch2_fs_quota_read(c);
 		if (ret)
 			goto err;
 		bch_verbose(c, "quotas done");
 	}
 
+	if (!(c->sb.compat & (1ULL << BCH_COMPAT_FEAT_EXTENTS_ABOVE_BTREE_UPDATES_DONE)) ||
+	    !(c->sb.compat & (1ULL << BCH_COMPAT_FEAT_BFORMAT_OVERFLOW_DONE))) {
+		struct bch_move_stats stats = { 0 };
+
+		bch_verbose(c, "scanning for old btree nodes");
+		ret = bch2_fs_read_write(c);
+		if (ret)
+			goto err;
+
+		ret = bch2_scan_old_btree_nodes(c, &stats);
+		if (ret)
+			goto err;
+		bch_verbose(c, "scanning for old btree nodes done");
+	}
+
 	mutex_lock(&c->sb_lock);
 	if (c->opts.version_upgrade) {
-		if (c->sb.version < bcachefs_metadata_version_new_versioning)
-			c->disk_sb.sb->version_min =
-				le16_to_cpu(bcachefs_metadata_version_min);
 		c->disk_sb.sb->version = le16_to_cpu(bcachefs_metadata_version_current);
+		c->disk_sb.sb->features[0] |= BCH_SB_FEATURES_ALL;
+		write_sb = true;
+	}
+
+	if (!test_bit(BCH_FS_ERROR, &c->flags)) {
+		c->disk_sb.sb->compat[0] |= 1ULL << BCH_COMPAT_FEAT_ALLOC_INFO;
+		write_sb = true;
 	}
 
 	if (c->opts.fsck &&
 	    !test_bit(BCH_FS_ERROR, &c->flags)) {
-		c->disk_sb.sb->features[0] |= 1ULL << BCH_FEATURE_ATOMIC_NLINK;
+		c->disk_sb.sb->features[0] |= 1ULL << BCH_FEATURE_atomic_nlink;
 		SET_BCH_SB_HAS_ERRORS(c->disk_sb.sb, 0);
+		write_sb = true;
 	}
+
+	if (write_sb)
+		bch2_write_super(c);
 	mutex_unlock(&c->sb_lock);
 
 	if (c->journal_seq_blacklist_table &&
 	    c->journal_seq_blacklist_table->nr > 128)
 		queue_work(system_long_wq, &c->journal_seq_blacklist_gc_work);
 out:
-	bch2_journal_entries_free(&journal);
-	kfree(clean);
-	return ret;
+	ret = 0;
 err:
 fsck_err:
-	pr_err("Error in recovery: %s (%i)", err, ret);
-	goto out;
+	set_bit(BCH_FS_FSCK_DONE, &c->flags);
+	bch2_flush_fsck_errs(c);
+
+	if (!c->opts.keep_journal) {
+		bch2_journal_keys_free(&c->journal_keys);
+		bch2_journal_entries_free(&c->journal_entries);
+	}
+	kfree(clean);
+	if (ret)
+		bch_err(c, "Error in recovery: %s (%i)", err, ret);
+	else
+		bch_verbose(c, "ret %i", ret);
+	return ret;
 }
 
 int bch2_fs_initialize(struct bch_fs *c)
 {
 	struct bch_inode_unpacked root_inode, lostfound_inode;
 	struct bkey_inode_buf packed_inode;
-	struct bch_hash_info root_hash_info;
 	struct qstr lostfound = QSTR("lost+found");
 	const char *err = "cannot allocate memory";
 	struct bch_dev *ca;
@@ -532,6 +1289,15 @@ int bch2_fs_initialize(struct bch_fs *c)
 	bch_notice(c, "initializing new filesystem");
 
 	mutex_lock(&c->sb_lock);
+	c->disk_sb.sb->compat[0] |= 1ULL << BCH_COMPAT_FEAT_EXTENTS_ABOVE_BTREE_UPDATES_DONE;
+	c->disk_sb.sb->compat[0] |= 1ULL << BCH_COMPAT_FEAT_BFORMAT_OVERFLOW_DONE;
+
+	if (c->opts.version_upgrade) {
+		c->disk_sb.sb->version = le16_to_cpu(bcachefs_metadata_version_current);
+		c->disk_sb.sb->features[0] |= BCH_SB_FEATURES_ALL;
+		bch2_write_super(c);
+	}
+
 	for_each_online_member(ca, c, i)
 		bch2_mark_dev_superblock(c, ca, 0);
 	mutex_unlock(&c->sb_lock);
@@ -542,6 +1308,9 @@ int bch2_fs_initialize(struct bch_fs *c)
 	for (i = 0; i < BTREE_ID_NR; i++)
 		bch2_btree_root_alloc(c, i);
 
+	set_bit(BCH_FS_BTREE_INTERIOR_REPLAY_DONE, &c->flags);
+	set_bit(JOURNAL_RECLAIM_STARTED, &c->journal.flags);
+
 	err = "unable to allocate journal buckets";
 	for_each_online_member(ca, c, i) {
 		ret = bch2_dev_journal_alloc(ca);
@@ -558,44 +1327,46 @@ int bch2_fs_initialize(struct bch_fs *c)
 	bch2_fs_journal_start(&c->journal, 1, &journal);
 	bch2_journal_set_replay_done(&c->journal);
 
-	err = "error going read write";
-	ret = __bch2_fs_read_write(c, true);
+	err = "error going read-write";
+	ret = bch2_fs_read_write_early(c);
+	if (ret)
+		goto err;
+
+	/*
+	 * Write out the superblock and journal buckets, now that we can do
+	 * btree updates
+	 */
+	err = "error writing alloc info";
+	ret = bch2_alloc_write(c, 0);
 	if (ret)
 		goto err;
 
 	bch2_inode_init(c, &root_inode, 0, 0,
 			S_IFDIR|S_IRWXU|S_IRUGO|S_IXUGO, 0, NULL);
 	root_inode.bi_inum = BCACHEFS_ROOT_INO;
-	root_inode.bi_nlink++; /* lost+found */
-	bch2_inode_pack(&packed_inode, &root_inode);
+	bch2_inode_pack(c, &packed_inode, &root_inode);
+	packed_inode.inode.k.p.snapshot = U32_MAX;
 
 	err = "error creating root directory";
-	ret = bch2_btree_insert(c, BTREE_ID_INODES,
+	ret = bch2_btree_insert(c, BTREE_ID_inodes,
 				&packed_inode.inode.k_i,
 				NULL, NULL, 0);
 	if (ret)
 		goto err;
 
-	bch2_inode_init(c, &lostfound_inode, 0, 0,
-			S_IFDIR|S_IRWXU|S_IRUGO|S_IXUGO, 0,
-			&root_inode);
-	lostfound_inode.bi_inum = BCACHEFS_ROOT_INO + 1;
-	bch2_inode_pack(&packed_inode, &lostfound_inode);
+	bch2_inode_init_early(c, &lostfound_inode);
 
 	err = "error creating lost+found";
-	ret = bch2_btree_insert(c, BTREE_ID_INODES,
-				&packed_inode.inode.k_i,
-				NULL, NULL, 0);
-	if (ret)
-		goto err;
-
-	root_hash_info = bch2_hash_info_init(c, &root_inode);
-
-	ret = bch2_dirent_create(c, BCACHEFS_ROOT_INO, &root_hash_info, DT_DIR,
-				 &lostfound, lostfound_inode.bi_inum, NULL,
-				 BTREE_INSERT_NOFAIL);
-	if (ret)
+	ret = bch2_trans_do(c, NULL, NULL, 0,
+		bch2_create_trans(&trans, BCACHEFS_ROOT_INO,
+				  &root_inode, &lostfound_inode,
+				  &lostfound,
+				  0, 0, S_IFDIR|0700, 0,
+				  NULL, NULL));
+	if (ret) {
+		bch_err(c, "error creating lost+found");
 		goto err;
+	}
 
 	if (enabled_qtypes(c)) {
 		ret = bch2_fs_quota_read(c);
@@ -609,10 +1380,6 @@ int bch2_fs_initialize(struct bch_fs *c)
 		goto err;
 
 	mutex_lock(&c->sb_lock);
-	c->disk_sb.sb->version = c->disk_sb.sb->version_min =
-		le16_to_cpu(bcachefs_metadata_version_current);
-	c->disk_sb.sb->features[0] |= 1ULL << BCH_FEATURE_ATOMIC_NLINK;
-
 	SET_BCH_SB_INITIALIZED(c->disk_sb.sb, true);
 	SET_BCH_SB_CLEAN(c->disk_sb.sb, false);