diff --git a/.bcachefs_revision b/.bcachefs_revision
index 0476cc0e..f7786253 100644
--- a/.bcachefs_revision
+++ b/.bcachefs_revision
@@ -1 +1 @@
-6628827a87075d3f807c974045ed293ac1e8965b
+b9bd69421f7364ca4ff11c827fd0e171a8b826ea
diff --git a/include/linux/generic-radix-tree.h b/include/linux/generic-radix-tree.h
index c74b7376..84741316 100644
--- a/include/linux/generic-radix-tree.h
+++ b/include/linux/generic-radix-tree.h
@@ -191,8 +191,8 @@ void *__genradix_iter_peek_prev(struct genradix_iter *, struct __genradix *,
 				size_t, size_t);
 
 /**
- * genradix_iter_peek - get first entry at or below iterator's current
- *			position
+ * genradix_iter_peek_prev - get first entry at or below iterator's current
+ *			     position
  * @_iter:	a genradix_iter
  * @_radix:	genradix being iterated over
  *
diff --git a/libbcachefs/alloc_background.c b/libbcachefs/alloc_background.c
index c342ec3b..bcfae916 100644
--- a/libbcachefs/alloc_background.c
+++ b/libbcachefs/alloc_background.c
@@ -2085,6 +2085,17 @@ void bch2_recalc_capacity(struct bch_fs *c)
 	closure_wake_up(&c->freelist_wait);
 }
 
+u64 bch2_min_rw_member_capacity(struct bch_fs *c)
+{
+	struct bch_dev *ca;
+	unsigned i;
+	u64 ret = U64_MAX;
+
+	for_each_rw_member(ca, c, i)
+		ret = min(ret, ca->mi.nbuckets * ca->mi.bucket_size);
+	return ret;
+}
+
 static bool bch2_dev_has_open_write_point(struct bch_fs *c, struct bch_dev *ca)
 {
 	struct open_bucket *ob;
diff --git a/libbcachefs/alloc_background.h b/libbcachefs/alloc_background.h
index e1ce38ef..73faf99a 100644
--- a/libbcachefs/alloc_background.h
+++ b/libbcachefs/alloc_background.h
@@ -249,6 +249,7 @@ int bch2_dev_freespace_init(struct bch_fs *, struct bch_dev *, u64, u64);
 int bch2_fs_freespace_init(struct bch_fs *);
 
 void bch2_recalc_capacity(struct bch_fs *);
+u64 bch2_min_rw_member_capacity(struct bch_fs *);
 
 void bch2_dev_allocator_remove(struct bch_fs *, struct bch_dev *);
 void bch2_dev_allocator_add(struct bch_fs *, struct bch_dev *);
diff --git a/libbcachefs/alloc_foreground.c b/libbcachefs/alloc_foreground.c
index 3bc4abd3..b85c7765 100644
--- a/libbcachefs/alloc_foreground.c
+++ b/libbcachefs/alloc_foreground.c
@@ -399,12 +399,23 @@ bch2_bucket_alloc_early(struct btree_trans *trans,
 			struct bucket_alloc_state *s,
 			struct closure *cl)
 {
-	struct btree_iter iter;
-	struct bkey_s_c k;
+	struct btree_iter iter, citer;
+	struct bkey_s_c k, ck;
 	struct open_bucket *ob = NULL;
-	u64 alloc_start = max_t(u64, ca->mi.first_bucket, ca->new_fs_bucket_idx);
-	u64 alloc_cursor = max(alloc_start, READ_ONCE(ca->alloc_cursor));
+	u64 first_bucket = max_t(u64, ca->mi.first_bucket, ca->new_fs_bucket_idx);
+	u64 alloc_start = max(first_bucket, READ_ONCE(ca->alloc_cursor));
+	u64 alloc_cursor = alloc_start;
 	int ret;
+
+	/*
+	 * Scan with an uncached iterator to avoid polluting the key cache. An
+	 * uncached iter will return a cached key if one exists, but if not
+	 * there is no other underlying protection for the associated key cache
+	 * slot. To avoid racing bucket allocations, look up the cached key slot
+	 * of any likely allocation candidate before attempting to proceed with
+	 * the allocation. This provides proper exclusion on the associated
+	 * bucket.
+	 */
 again:
 	for_each_btree_key_norestart(trans, iter, BTREE_ID_alloc, POS(ca->dev_idx, alloc_cursor),
 			   BTREE_ITER_SLOTS, k, ret) {
@@ -419,25 +430,38 @@ again:
 			continue;
 
 		a = bch2_alloc_to_v4(k, &a_convert);
-
 		if (a->data_type != BCH_DATA_free)
 			continue;
 
+		/* now check the cached key to serialize concurrent allocs of the bucket */
+		ck = bch2_bkey_get_iter(trans, &citer, BTREE_ID_alloc, k.k->p, BTREE_ITER_CACHED);
+		ret = bkey_err(ck);
+		if (ret)
+			break;
+
+		a = bch2_alloc_to_v4(ck, &a_convert);
+		if (a->data_type != BCH_DATA_free)
+			goto next;
+
 		s->buckets_seen++;
 
 		ob = __try_alloc_bucket(trans->c, ca, k.k->p.offset, watermark, a, s, cl);
+next:
+		citer.path->preserve = false;
+		bch2_trans_iter_exit(trans, &citer);
 		if (ob)
 			break;
 	}
 	bch2_trans_iter_exit(trans, &iter);
 
+	alloc_cursor = iter.pos.offset;
 	ca->alloc_cursor = alloc_cursor;
 
 	if (!ob && ret)
 		ob = ERR_PTR(ret);
 
-	if (!ob && alloc_cursor > alloc_start) {
-		alloc_cursor = alloc_start;
+	if (!ob && alloc_start > first_bucket) {
+		alloc_cursor = alloc_start = first_bucket;
 		goto again;
 	}
 
diff --git a/libbcachefs/bcachefs_format.h b/libbcachefs/bcachefs_format.h
index 29b000c6..7a1c2440 100644
--- a/libbcachefs/bcachefs_format.h
+++ b/libbcachefs/bcachefs_format.h
@@ -824,34 +824,30 @@ enum inode_opt_id {
 	Inode_opt_nr,
 };
 
-enum {
-	/*
-	 * User flags (get/settable with FS_IOC_*FLAGS, correspond to FS_*_FL
-	 * flags)
-	 */
-	__BCH_INODE_SYNC		= 0,
-	__BCH_INODE_IMMUTABLE		= 1,
-	__BCH_INODE_APPEND		= 2,
-	__BCH_INODE_NODUMP		= 3,
-	__BCH_INODE_NOATIME		= 4,
+#define BCH_INODE_FLAGS()			\
+	x(sync,				0)	\
+	x(immutable,			1)	\
+	x(append,			2)	\
+	x(nodump,			3)	\
+	x(noatime,			4)	\
+	x(i_size_dirty,			5)	\
+	x(i_sectors_dirty,		6)	\
+	x(unlinked,			7)	\
+	x(backptr_untrusted,		8)
 
-	__BCH_INODE_I_SIZE_DIRTY	= 5, /* obsolete */
-	__BCH_INODE_I_SECTORS_DIRTY	= 6, /* obsolete */
-	__BCH_INODE_UNLINKED		= 7,
-	__BCH_INODE_BACKPTR_UNTRUSTED	= 8,
+/* bits 20+ reserved for packed fields below: */
 
-	/* bits 20+ reserved for packed fields below: */
+enum bch_inode_flags {
+#define x(t, n)	BCH_INODE_##t = 1U << n,
+	BCH_INODE_FLAGS()
+#undef x
 };
 
-#define BCH_INODE_SYNC		(1 << __BCH_INODE_SYNC)
-#define BCH_INODE_IMMUTABLE	(1 << __BCH_INODE_IMMUTABLE)
-#define BCH_INODE_APPEND	(1 << __BCH_INODE_APPEND)
-#define BCH_INODE_NODUMP	(1 << __BCH_INODE_NODUMP)
-#define BCH_INODE_NOATIME	(1 << __BCH_INODE_NOATIME)
-#define BCH_INODE_I_SIZE_DIRTY	(1 << __BCH_INODE_I_SIZE_DIRTY)
-#define BCH_INODE_I_SECTORS_DIRTY (1 << __BCH_INODE_I_SECTORS_DIRTY)
-#define BCH_INODE_UNLINKED	(1 << __BCH_INODE_UNLINKED)
-#define BCH_INODE_BACKPTR_UNTRUSTED (1 << __BCH_INODE_BACKPTR_UNTRUSTED)
+enum __bch_inode_flags {
+#define x(t, n)	__BCH_INODE_##t = n,
+	BCH_INODE_FLAGS()
+#undef x
+};
 
 LE32_BITMASK(INODE_STR_HASH,	struct bch_inode, bi_flags, 20, 24);
 LE32_BITMASK(INODE_NR_FIELDS,	struct bch_inode, bi_flags, 24, 31);
@@ -1617,9 +1613,7 @@ struct journal_seq_blacklist_entry {
 
 struct bch_sb_field_journal_seq_blacklist {
 	struct bch_sb_field	field;
-
-	struct journal_seq_blacklist_entry start[0];
-	__u64			_data[];
+	struct journal_seq_blacklist_entry start[];
 };
 
 struct bch_sb_field_errors {
diff --git a/libbcachefs/btree_iter.c b/libbcachefs/btree_iter.c
index feba9a31..ba392eb0 100644
--- a/libbcachefs/btree_iter.c
+++ b/libbcachefs/btree_iter.c
@@ -1109,6 +1109,9 @@ int bch2_btree_path_traverse_one(struct btree_trans *trans,
 	if (unlikely(ret))
 		goto out;
 
+	if (unlikely(!trans->srcu_held))
+		bch2_trans_srcu_lock(trans);
+
 	/*
 	 * Ensure we obey path->should_be_locked: if it's set, we can't unlock
 	 * and re-traverse the path without a transaction restart:
@@ -2830,18 +2833,35 @@ void *__bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
 	return p;
 }
 
-static noinline void bch2_trans_reset_srcu_lock(struct btree_trans *trans)
+static inline void check_srcu_held_too_long(struct btree_trans *trans)
 {
-	struct bch_fs *c = trans->c;
-	struct btree_path *path;
+	WARN(time_after(jiffies, trans->srcu_lock_time + HZ * 10),
+	     "btree trans held srcu lock (delaying memory reclaim) by more than 10 seconds");
+}
 
-	trans_for_each_path(trans, path)
-		if (path->cached && !btree_node_locked(path, 0))
-			path->l[0].b = ERR_PTR(-BCH_ERR_no_btree_node_srcu_reset);
+void bch2_trans_srcu_unlock(struct btree_trans *trans)
+{
+	if (trans->srcu_held) {
+		struct bch_fs *c = trans->c;
+		struct btree_path *path;
 
-	srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
-	trans->srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
-	trans->srcu_lock_time	= jiffies;
+		trans_for_each_path(trans, path)
+			if (path->cached && !btree_node_locked(path, 0))
+				path->l[0].b = ERR_PTR(-BCH_ERR_no_btree_node_srcu_reset);
+
+		check_srcu_held_too_long(trans);
+		srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
+		trans->srcu_held = false;
+	}
+}
+
+void bch2_trans_srcu_lock(struct btree_trans *trans)
+{
+	if (!trans->srcu_held) {
+		trans->srcu_idx = srcu_read_lock(&trans->c->btree_trans_barrier);
+		trans->srcu_lock_time	= jiffies;
+		trans->srcu_held = true;
+	}
 }
 
 /**
@@ -2895,8 +2915,9 @@ u32 bch2_trans_begin(struct btree_trans *trans)
 	}
 	trans->last_begin_time = now;
 
-	if (unlikely(time_after(jiffies, trans->srcu_lock_time + msecs_to_jiffies(10))))
-		bch2_trans_reset_srcu_lock(trans);
+	if (unlikely(trans->srcu_held &&
+		     time_after(jiffies, trans->srcu_lock_time + msecs_to_jiffies(10))))
+		bch2_trans_srcu_unlock(trans);
 
 	trans->last_begin_ip = _RET_IP_;
 	if (trans->restarted) {
@@ -2983,8 +3004,9 @@ struct btree_trans *__bch2_trans_get(struct bch_fs *c, unsigned fn_idx)
 		trans->wb_updates_size = s->wb_updates_size;
 	}
 
-	trans->srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
+	trans->srcu_idx		= srcu_read_lock(&c->btree_trans_barrier);
 	trans->srcu_lock_time	= jiffies;
+	trans->srcu_held	= true;
 
 	if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG_TRANSACTIONS)) {
 		struct btree_trans *pos;
@@ -3061,7 +3083,10 @@ void bch2_trans_put(struct btree_trans *trans)
 
 	check_btree_paths_leaked(trans);
 
-	srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
+	if (trans->srcu_held) {
+		check_srcu_held_too_long(trans);
+		srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
+	}
 
 	bch2_journal_preres_put(&c->journal, &trans->journal_preres);
 
diff --git a/libbcachefs/btree_iter.h b/libbcachefs/btree_iter.h
index 70759ee3..5e103f51 100644
--- a/libbcachefs/btree_iter.h
+++ b/libbcachefs/btree_iter.h
@@ -274,6 +274,7 @@ void bch2_path_put(struct btree_trans *, struct btree_path *, bool);
 int bch2_trans_relock(struct btree_trans *);
 int bch2_trans_relock_notrace(struct btree_trans *);
 void bch2_trans_unlock(struct btree_trans *);
+void bch2_trans_unlock_long(struct btree_trans *);
 bool bch2_trans_locked(struct btree_trans *);
 
 static inline int trans_was_restarted(struct btree_trans *trans, u32 restart_count)
@@ -579,6 +580,9 @@ static inline int __bch2_bkey_get_val_typed(struct btree_trans *trans,
 	__bch2_bkey_get_val_typed(_trans, _btree_id, _pos, _flags,	\
 				  KEY_TYPE_##_type, sizeof(*_val), _val)
 
+void bch2_trans_srcu_unlock(struct btree_trans *);
+void bch2_trans_srcu_lock(struct btree_trans *);
+
 u32 bch2_trans_begin(struct btree_trans *);
 
 /*
diff --git a/libbcachefs/btree_locking.c b/libbcachefs/btree_locking.c
index ba263302..c4266835 100644
--- a/libbcachefs/btree_locking.c
+++ b/libbcachefs/btree_locking.c
@@ -759,6 +759,12 @@ void bch2_trans_unlock(struct btree_trans *trans)
 		bch2_assert_btree_nodes_not_locked();
 }
 
+void bch2_trans_unlock_long(struct btree_trans *trans)
+{
+	bch2_trans_unlock(trans);
+	bch2_trans_srcu_unlock(trans);
+}
+
 bool bch2_trans_locked(struct btree_trans *trans)
 {
 	struct btree_path *path;
diff --git a/libbcachefs/btree_trans_commit.c b/libbcachefs/btree_trans_commit.c
index 8140b6e6..32693f7c 100644
--- a/libbcachefs/btree_trans_commit.c
+++ b/libbcachefs/btree_trans_commit.c
@@ -681,7 +681,7 @@ bch2_trans_commit_write_locked(struct btree_trans *trans, unsigned flags,
 						       BCH_JSET_ENTRY_overwrite,
 						       i->btree_id, i->level,
 						       i->old_k.u64s);
-				bkey_reassemble(&entry->start[0],
+				bkey_reassemble((struct bkey_i *) entry->start,
 						(struct bkey_s_c) { &i->old_k, i->old_v });
 			}
 
@@ -689,7 +689,7 @@ bch2_trans_commit_write_locked(struct btree_trans *trans, unsigned flags,
 					       BCH_JSET_ENTRY_btree_keys,
 					       i->btree_id, i->level,
 					       i->k->k.u64s);
-			bkey_copy(&entry->start[0], i->k);
+			bkey_copy((struct bkey_i *) entry->start, i->k);
 		}
 
 		trans_for_each_wb_update(trans, wb) {
@@ -697,7 +697,7 @@ bch2_trans_commit_write_locked(struct btree_trans *trans, unsigned flags,
 					       BCH_JSET_ENTRY_btree_keys,
 					       wb->btree, 0,
 					       wb->k.k.u64s);
-			bkey_copy(&entry->start[0], &wb->k);
+			bkey_copy((struct bkey_i *) entry->start, &wb->k);
 		}
 
 		if (trans->journal_seq)
diff --git a/libbcachefs/btree_types.h b/libbcachefs/btree_types.h
index cbcb04a4..4b9cc61a 100644
--- a/libbcachefs/btree_types.h
+++ b/libbcachefs/btree_types.h
@@ -432,6 +432,7 @@ struct btree_trans {
 	u8			nr_updates;
 	u8			nr_wb_updates;
 	u8			wb_updates_size;
+	bool			srcu_held:1;
 	bool			used_mempool:1;
 	bool			in_traverse_all:1;
 	bool			paths_sorted:1;
diff --git a/libbcachefs/btree_update_interior.c b/libbcachefs/btree_update_interior.c
index d029e034..89ada89e 100644
--- a/libbcachefs/btree_update_interior.c
+++ b/libbcachefs/btree_update_interior.c
@@ -2411,7 +2411,7 @@ void bch2_journal_entry_to_btree_root(struct bch_fs *c, struct jset_entry *entry
 
 	r->level = entry->level;
 	r->alive = true;
-	bkey_copy(&r->key, &entry->start[0]);
+	bkey_copy(&r->key, (struct bkey_i *) entry->start);
 
 	mutex_unlock(&c->btree_root_lock);
 }
diff --git a/libbcachefs/btree_update_interior.h b/libbcachefs/btree_update_interior.h
index 5e0a467f..d92b3cf5 100644
--- a/libbcachefs/btree_update_interior.h
+++ b/libbcachefs/btree_update_interior.h
@@ -271,7 +271,7 @@ static inline struct btree_node_entry *want_new_bset(struct bch_fs *c,
 	struct btree_node_entry *bne = max(write_block(b),
 			(void *) btree_bkey_last(b, bset_tree_last(b)));
 	ssize_t remaining_space =
-		__bch_btree_u64s_remaining(c, b, &bne->keys.start[0]);
+		__bch_btree_u64s_remaining(c, b, bne->keys.start);
 
 	if (unlikely(bset_written(b, bset(b, t)))) {
 		if (remaining_space > (ssize_t) (block_bytes(c) >> 3))
diff --git a/libbcachefs/darray.h b/libbcachefs/darray.h
index 114f86b4..87b4b2d1 100644
--- a/libbcachefs/darray.h
+++ b/libbcachefs/darray.h
@@ -69,9 +69,15 @@ static inline int __darray_make_room(darray_void *d, size_t t_size, size_t more,
 	_ret;								\
 })
 
+#define darray_remove_item(_d, _pos)					\
+	array_remove_item((_d)->data, (_d)->nr, (_pos) - (_d)->data)
+
 #define darray_for_each(_d, _i)						\
 	for (_i = (_d).data; _i < (_d).data + (_d).nr; _i++)
 
+#define darray_for_each_reverse(_d, _i)					\
+	for (_i = (_d).data + (_d).nr - 1; _i >= (_d).data; --_i)
+
 #define darray_init(_d)							\
 do {									\
 	(_d)->data = NULL;						\
diff --git a/libbcachefs/fs-common.c b/libbcachefs/fs-common.c
index bb530544..4496cf91 100644
--- a/libbcachefs/fs-common.c
+++ b/libbcachefs/fs-common.c
@@ -51,7 +51,7 @@ int bch2_create_trans(struct btree_trans *trans,
 		bch2_inode_init_late(new_inode, now, uid, gid, mode, rdev, dir_u);
 
 		if (flags & BCH_CREATE_TMPFILE)
-			new_inode->bi_flags |= BCH_INODE_UNLINKED;
+			new_inode->bi_flags |= BCH_INODE_unlinked;
 
 		ret = bch2_inode_create(trans, &inode_iter, new_inode, snapshot, cpu);
 		if (ret)
diff --git a/libbcachefs/fs-ioctl.c b/libbcachefs/fs-ioctl.c
index 6040bd3f..5a39bcb5 100644
--- a/libbcachefs/fs-ioctl.c
+++ b/libbcachefs/fs-ioctl.c
@@ -45,13 +45,13 @@ static int bch2_inode_flags_set(struct btree_trans *trans,
 	unsigned newflags = s->flags;
 	unsigned oldflags = bi->bi_flags & s->mask;
 
-	if (((newflags ^ oldflags) & (BCH_INODE_APPEND|BCH_INODE_IMMUTABLE)) &&
+	if (((newflags ^ oldflags) & (BCH_INODE_append|BCH_INODE_immutable)) &&
 	    !capable(CAP_LINUX_IMMUTABLE))
 		return -EPERM;
 
 	if (!S_ISREG(bi->bi_mode) &&
 	    !S_ISDIR(bi->bi_mode) &&
-	    (newflags & (BCH_INODE_NODUMP|BCH_INODE_NOATIME)) != newflags)
+	    (newflags & (BCH_INODE_nodump|BCH_INODE_noatime)) != newflags)
 		return -EINVAL;
 
 	if (s->set_projinherit) {
diff --git a/libbcachefs/fs-ioctl.h b/libbcachefs/fs-ioctl.h
index 54a9c21a..d30f9bb0 100644
--- a/libbcachefs/fs-ioctl.h
+++ b/libbcachefs/fs-ioctl.h
@@ -6,28 +6,28 @@
 
 /* bcachefs inode flags -> vfs inode flags: */
 static const __maybe_unused unsigned bch_flags_to_vfs[] = {
-	[__BCH_INODE_SYNC]	= S_SYNC,
-	[__BCH_INODE_IMMUTABLE]	= S_IMMUTABLE,
-	[__BCH_INODE_APPEND]	= S_APPEND,
-	[__BCH_INODE_NOATIME]	= S_NOATIME,
+	[__BCH_INODE_sync]	= S_SYNC,
+	[__BCH_INODE_immutable]	= S_IMMUTABLE,
+	[__BCH_INODE_append]	= S_APPEND,
+	[__BCH_INODE_noatime]	= S_NOATIME,
 };
 
 /* bcachefs inode flags -> FS_IOC_GETFLAGS: */
 static const __maybe_unused unsigned bch_flags_to_uflags[] = {
-	[__BCH_INODE_SYNC]	= FS_SYNC_FL,
-	[__BCH_INODE_IMMUTABLE]	= FS_IMMUTABLE_FL,
-	[__BCH_INODE_APPEND]	= FS_APPEND_FL,
-	[__BCH_INODE_NODUMP]	= FS_NODUMP_FL,
-	[__BCH_INODE_NOATIME]	= FS_NOATIME_FL,
+	[__BCH_INODE_sync]	= FS_SYNC_FL,
+	[__BCH_INODE_immutable]	= FS_IMMUTABLE_FL,
+	[__BCH_INODE_append]	= FS_APPEND_FL,
+	[__BCH_INODE_nodump]	= FS_NODUMP_FL,
+	[__BCH_INODE_noatime]	= FS_NOATIME_FL,
 };
 
 /* bcachefs inode flags -> FS_IOC_FSGETXATTR: */
 static const __maybe_unused unsigned bch_flags_to_xflags[] = {
-	[__BCH_INODE_SYNC]	= FS_XFLAG_SYNC,
-	[__BCH_INODE_IMMUTABLE]	= FS_XFLAG_IMMUTABLE,
-	[__BCH_INODE_APPEND]	= FS_XFLAG_APPEND,
-	[__BCH_INODE_NODUMP]	= FS_XFLAG_NODUMP,
-	[__BCH_INODE_NOATIME]	= FS_XFLAG_NOATIME,
+	[__BCH_INODE_sync]	= FS_XFLAG_SYNC,
+	[__BCH_INODE_immutable]	= FS_XFLAG_IMMUTABLE,
+	[__BCH_INODE_append]	= FS_XFLAG_APPEND,
+	[__BCH_INODE_nodump]	= FS_XFLAG_NODUMP,
+	[__BCH_INODE_noatime]	= FS_XFLAG_NOATIME,
 	//[__BCH_INODE_PROJINHERIT] = FS_XFLAG_PROJINHERIT;
 };
 
diff --git a/libbcachefs/fs.c b/libbcachefs/fs.c
index 89759e6a..693f3474 100644
--- a/libbcachefs/fs.c
+++ b/libbcachefs/fs.c
@@ -66,11 +66,11 @@ void bch2_inode_update_after_write(struct btree_trans *trans,
 	inode->v.i_mode	= bi->bi_mode;
 
 	if (fields & ATTR_ATIME)
-		inode->v.i_atime = bch2_time_to_timespec(c, bi->bi_atime);
+		inode_set_atime_to_ts(&inode->v, bch2_time_to_timespec(c, bi->bi_atime));
 	if (fields & ATTR_MTIME)
-		inode->v.i_mtime = bch2_time_to_timespec(c, bi->bi_mtime);
+		inode_set_mtime_to_ts(&inode->v, bch2_time_to_timespec(c, bi->bi_mtime));
 	if (fields & ATTR_CTIME)
-		inode->v.i_ctime = bch2_time_to_timespec(c, bi->bi_ctime);
+		inode_set_ctime_to_ts(&inode->v, bch2_time_to_timespec(c, bi->bi_ctime));
 
 	inode->ei_inode		= *bi;
 
@@ -753,9 +753,9 @@ static int bch2_getattr(struct mnt_idmap *idmap,
 	stat->gid	= inode->v.i_gid;
 	stat->rdev	= inode->v.i_rdev;
 	stat->size	= i_size_read(&inode->v);
-	stat->atime	= inode->v.i_atime;
-	stat->mtime	= inode->v.i_mtime;
-	stat->ctime	= inode->v.i_ctime;
+	stat->atime	= inode_get_atime(&inode->v);
+	stat->mtime	= inode_get_mtime(&inode->v);
+	stat->ctime	= inode_get_ctime(&inode->v);
 	stat->blksize	= block_bytes(c);
 	stat->blocks	= inode->v.i_blocks;
 
@@ -764,15 +764,15 @@ static int bch2_getattr(struct mnt_idmap *idmap,
 		stat->btime = bch2_time_to_timespec(c, inode->ei_inode.bi_otime);
 	}
 
-	if (inode->ei_inode.bi_flags & BCH_INODE_IMMUTABLE)
+	if (inode->ei_inode.bi_flags & BCH_INODE_immutable)
 		stat->attributes |= STATX_ATTR_IMMUTABLE;
 	stat->attributes_mask	 |= STATX_ATTR_IMMUTABLE;
 
-	if (inode->ei_inode.bi_flags & BCH_INODE_APPEND)
+	if (inode->ei_inode.bi_flags & BCH_INODE_append)
 		stat->attributes |= STATX_ATTR_APPEND;
 	stat->attributes_mask	 |= STATX_ATTR_APPEND;
 
-	if (inode->ei_inode.bi_flags & BCH_INODE_NODUMP)
+	if (inode->ei_inode.bi_flags & BCH_INODE_nodump)
 		stat->attributes |= STATX_ATTR_NODUMP;
 	stat->attributes_mask	 |= STATX_ATTR_NODUMP;
 
@@ -1418,9 +1418,9 @@ static int inode_update_times_fn(struct btree_trans *trans,
 {
 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
 
-	bi->bi_atime	= timespec_to_bch2_time(c, inode->v.i_atime);
-	bi->bi_mtime	= timespec_to_bch2_time(c, inode->v.i_mtime);
-	bi->bi_ctime	= timespec_to_bch2_time(c, inode->v.i_ctime);
+	bi->bi_atime	= timespec_to_bch2_time(c, inode_get_atime(&inode->v));
+	bi->bi_mtime	= timespec_to_bch2_time(c, inode_get_mtime(&inode->v));
+	bi->bi_ctime	= timespec_to_bch2_time(c, inode_get_ctime(&inode->v));
 
 	return 0;
 }
diff --git a/libbcachefs/fsck.c b/libbcachefs/fsck.c
index 0e470ebd..9f3e9bd3 100644
--- a/libbcachefs/fsck.c
+++ b/libbcachefs/fsck.c
@@ -854,9 +854,9 @@ static int check_inode(struct btree_trans *trans,
 	BUG_ON(bch2_inode_unpack(k, &u));
 
 	if (!full &&
-	    !(u.bi_flags & (BCH_INODE_I_SIZE_DIRTY|
-			    BCH_INODE_I_SECTORS_DIRTY|
-			    BCH_INODE_UNLINKED)))
+	    !(u.bi_flags & (BCH_INODE_i_size_dirty|
+			    BCH_INODE_i_sectors_dirty|
+			    BCH_INODE_unlinked)))
 		return 0;
 
 	if (prev->bi_inum != u.bi_inum)
@@ -870,7 +870,7 @@ static int check_inode(struct btree_trans *trans,
 		return -EINVAL;
 	}
 
-	if ((u.bi_flags & (BCH_INODE_I_SIZE_DIRTY|BCH_INODE_UNLINKED)) &&
+	if ((u.bi_flags & (BCH_INODE_i_size_dirty|BCH_INODE_unlinked)) &&
 	    bch2_key_has_snapshot_overwrites(trans, BTREE_ID_inodes, k.k->p)) {
 		struct bpos new_min_pos;
 
@@ -878,7 +878,7 @@ static int check_inode(struct btree_trans *trans,
 		if (ret)
 			goto err;
 
-		u.bi_flags &= ~BCH_INODE_I_SIZE_DIRTY|BCH_INODE_UNLINKED;
+		u.bi_flags &= ~BCH_INODE_i_size_dirty|BCH_INODE_unlinked;
 
 		ret = __write_inode(trans, &u, iter->pos.snapshot);
 		bch_err_msg(c, ret, "in fsck updating inode");
@@ -890,7 +890,7 @@ static int check_inode(struct btree_trans *trans,
 		return 0;
 	}
 
-	if (u.bi_flags & BCH_INODE_UNLINKED &&
+	if (u.bi_flags & BCH_INODE_unlinked &&
 	    (!c->sb.clean ||
 	     fsck_err(c, inode_unlinked_but_clean,
 		      "filesystem marked clean, but inode %llu unlinked",
@@ -903,7 +903,7 @@ static int check_inode(struct btree_trans *trans,
 		return ret;
 	}
 
-	if (u.bi_flags & BCH_INODE_I_SIZE_DIRTY &&
+	if (u.bi_flags & BCH_INODE_i_size_dirty &&
 	    (!c->sb.clean ||
 	     fsck_err(c, inode_i_size_dirty_but_clean,
 		      "filesystem marked clean, but inode %llu has i_size dirty",
@@ -930,13 +930,13 @@ static int check_inode(struct btree_trans *trans,
 		 * We truncated without our normal sector accounting hook, just
 		 * make sure we recalculate it:
 		 */
-		u.bi_flags |= BCH_INODE_I_SECTORS_DIRTY;
+		u.bi_flags |= BCH_INODE_i_sectors_dirty;
 
-		u.bi_flags &= ~BCH_INODE_I_SIZE_DIRTY;
+		u.bi_flags &= ~BCH_INODE_i_size_dirty;
 		do_update = true;
 	}
 
-	if (u.bi_flags & BCH_INODE_I_SECTORS_DIRTY &&
+	if (u.bi_flags & BCH_INODE_i_sectors_dirty &&
 	    (!c->sb.clean ||
 	     fsck_err(c, inode_i_sectors_dirty_but_clean,
 		      "filesystem marked clean, but inode %llu has i_sectors dirty",
@@ -953,14 +953,14 @@ static int check_inode(struct btree_trans *trans,
 		}
 
 		u.bi_sectors = sectors;
-		u.bi_flags &= ~BCH_INODE_I_SECTORS_DIRTY;
+		u.bi_flags &= ~BCH_INODE_i_sectors_dirty;
 		do_update = true;
 	}
 
-	if (u.bi_flags & BCH_INODE_BACKPTR_UNTRUSTED) {
+	if (u.bi_flags & BCH_INODE_backptr_untrusted) {
 		u.bi_dir = 0;
 		u.bi_dir_offset = 0;
-		u.bi_flags &= ~BCH_INODE_BACKPTR_UNTRUSTED;
+		u.bi_flags &= ~BCH_INODE_backptr_untrusted;
 		do_update = true;
 	}
 
@@ -1065,7 +1065,7 @@ static int check_i_sectors(struct btree_trans *trans, struct inode_walker *w)
 			return -BCH_ERR_internal_fsck_err;
 		}
 
-		if (fsck_err_on(!(i->inode.bi_flags & BCH_INODE_I_SECTORS_DIRTY),
+		if (fsck_err_on(!(i->inode.bi_flags & BCH_INODE_i_sectors_dirty),
 				c, inode_i_sectors_wrong,
 				"inode %llu:%u has incorrect i_sectors: got %llu, should be %llu",
 				w->last_pos.inode, i->snapshot,
@@ -1405,7 +1405,7 @@ static int check_extent(struct btree_trans *trans, struct btree_iter *iter,
 			continue;
 
 		if (k.k->type != KEY_TYPE_whiteout) {
-			if (fsck_err_on(!(i->inode.bi_flags & BCH_INODE_I_SIZE_DIRTY) &&
+			if (fsck_err_on(!(i->inode.bi_flags & BCH_INODE_i_size_dirty) &&
 					k.k->p.offset > round_up(i->inode.bi_size, block_bytes(c)) >> 9 &&
 					!bkey_extent_is_reservation(k),
 					c, extent_past_end_of_inode,
@@ -1588,7 +1588,7 @@ static int check_dirent_target(struct btree_trans *trans,
 				"inode %llu type %s has multiple links but i_nlink 0",
 				target->bi_inum, bch2_d_types[d.v->d_type])) {
 			target->bi_nlink++;
-			target->bi_flags &= ~BCH_INODE_UNLINKED;
+			target->bi_flags &= ~BCH_INODE_unlinked;
 
 			ret = __write_inode(trans, target, target_snapshot);
 			if (ret)
@@ -2160,7 +2160,7 @@ int bch2_check_directory_structure(struct bch_fs *c)
 			break;
 		}
 
-		if (u.bi_flags & BCH_INODE_UNLINKED)
+		if (u.bi_flags & BCH_INODE_unlinked)
 			continue;
 
 		ret = check_path(trans, &path, &u, iter.pos.snapshot);
diff --git a/libbcachefs/inode.c b/libbcachefs/inode.c
index 925d1b7f..8b3c675e 100644
--- a/libbcachefs/inode.c
+++ b/libbcachefs/inode.c
@@ -20,13 +20,18 @@
 
 #include <asm/unaligned.h>
 
-const char * const bch2_inode_opts[] = {
 #define x(name, ...)	#name,
+const char * const bch2_inode_opts[] = {
 	BCH_INODE_OPTS()
-#undef  x
 	NULL,
 };
 
+static const char * const bch2_inode_flag_strs[] = {
+	BCH_INODE_FLAGS()
+	NULL
+};
+#undef  x
+
 static const u8 byte_table[8] = { 1, 2, 3, 4, 6, 8, 10, 13 };
 
 static int inode_decode_field(const u8 *in, const u8 *end,
@@ -425,7 +430,7 @@ static int __bch2_inode_invalid(struct bch_fs *c, struct bkey_s_c k, struct prin
 			 inode_compression_type_invalid,
 			 "invalid compression opt %u", unpacked.bi_compression - 1);
 
-	bkey_fsck_err_on((unpacked.bi_flags & BCH_INODE_UNLINKED) &&
+	bkey_fsck_err_on((unpacked.bi_flags & BCH_INODE_unlinked) &&
 			 unpacked.bi_nlink != 0, c, err,
 			 inode_unlinked_but_nlink_nonzero,
 			 "flagged as unlinked but bi_nlink != 0");
@@ -499,15 +504,20 @@ fsck_err:
 static void __bch2_inode_unpacked_to_text(struct printbuf *out,
 					  struct bch_inode_unpacked *inode)
 {
-	prt_printf(out, "mode %o flags %x journal_seq %llu bi_size %llu bi_sectors %llu bi_version %llu",
-	       inode->bi_mode, inode->bi_flags,
+	prt_printf(out, "mode=%o ", inode->bi_mode);
+
+	prt_str(out, "flags=");
+	prt_bitflags(out, bch2_inode_flag_strs, inode->bi_flags & ((1U << 20) - 1));
+	prt_printf(out, " (%x)", inode->bi_flags);
+
+	prt_printf(out, " journal_seq=%llu bi_size=%llu bi_sectors=%llu bi_version=%llu",
 	       inode->bi_journal_seq,
 	       inode->bi_size,
 	       inode->bi_sectors,
 	       inode->bi_version);
 
 #define x(_name, _bits)						\
-	prt_printf(out, " "#_name " %llu", (u64) inode->_name);
+	prt_printf(out, " "#_name "=%llu", (u64) inode->_name);
 	BCH_INODE_FIELDS_v3()
 #undef  x
 }
@@ -546,7 +556,7 @@ static inline u64 bkey_inode_flags(struct bkey_s_c k)
 
 static inline bool bkey_is_deleted_inode(struct bkey_s_c k)
 {
-	return bkey_inode_flags(k) & BCH_INODE_UNLINKED;
+	return bkey_inode_flags(k) & BCH_INODE_unlinked;
 }
 
 int bch2_trans_mark_inode(struct btree_trans *trans,
@@ -927,8 +937,8 @@ int bch2_inode_find_by_inum(struct bch_fs *c, subvol_inum inum,
 
 int bch2_inode_nlink_inc(struct bch_inode_unpacked *bi)
 {
-	if (bi->bi_flags & BCH_INODE_UNLINKED)
-		bi->bi_flags &= ~BCH_INODE_UNLINKED;
+	if (bi->bi_flags & BCH_INODE_unlinked)
+		bi->bi_flags &= ~BCH_INODE_unlinked;
 	else {
 		if (bi->bi_nlink == U32_MAX)
 			return -EINVAL;
@@ -941,13 +951,13 @@ int bch2_inode_nlink_inc(struct bch_inode_unpacked *bi)
 
 void bch2_inode_nlink_dec(struct btree_trans *trans, struct bch_inode_unpacked *bi)
 {
-	if (bi->bi_nlink && (bi->bi_flags & BCH_INODE_UNLINKED)) {
+	if (bi->bi_nlink && (bi->bi_flags & BCH_INODE_unlinked)) {
 		bch2_trans_inconsistent(trans, "inode %llu unlinked but link count nonzero",
 					bi->bi_inum);
 		return;
 	}
 
-	if (bi->bi_flags & BCH_INODE_UNLINKED) {
+	if (bi->bi_flags & BCH_INODE_unlinked) {
 		bch2_trans_inconsistent(trans, "inode %llu link count underflow", bi->bi_inum);
 		return;
 	}
@@ -955,7 +965,7 @@ void bch2_inode_nlink_dec(struct btree_trans *trans, struct bch_inode_unpacked *
 	if (bi->bi_nlink)
 		bi->bi_nlink--;
 	else
-		bi->bi_flags |= BCH_INODE_UNLINKED;
+		bi->bi_flags |= BCH_INODE_unlinked;
 }
 
 struct bch_opts bch2_inode_opts_to_opts(struct bch_inode_unpacked *inode)
@@ -1094,7 +1104,7 @@ static int may_delete_deleted_inode(struct btree_trans *trans, struct bpos pos)
 			pos.offset, pos.snapshot))
 		goto delete;
 
-	if (fsck_err_on(!(inode.bi_flags & BCH_INODE_UNLINKED), c,
+	if (fsck_err_on(!(inode.bi_flags & BCH_INODE_unlinked), c,
 			deleted_inode_not_unlinked,
 			"non-deleted inode %llu:%u in deleted_inodes btree",
 			pos.offset, pos.snapshot))
diff --git a/libbcachefs/inode.h b/libbcachefs/inode.h
index 74c62e6c..5068ba9c 100644
--- a/libbcachefs/inode.h
+++ b/libbcachefs/inode.h
@@ -177,7 +177,7 @@ static inline unsigned nlink_bias(umode_t mode)
 
 static inline unsigned bch2_inode_nlink_get(struct bch_inode_unpacked *bi)
 {
-	return bi->bi_flags & BCH_INODE_UNLINKED
+	return bi->bi_flags & BCH_INODE_unlinked
 		  ? 0
 		  : bi->bi_nlink + nlink_bias(bi->bi_mode);
 }
@@ -187,10 +187,10 @@ static inline void bch2_inode_nlink_set(struct bch_inode_unpacked *bi,
 {
 	if (nlink) {
 		bi->bi_nlink = nlink - nlink_bias(bi->bi_mode);
-		bi->bi_flags &= ~BCH_INODE_UNLINKED;
+		bi->bi_flags &= ~BCH_INODE_unlinked;
 	} else {
 		bi->bi_nlink = 0;
-		bi->bi_flags |= BCH_INODE_UNLINKED;
+		bi->bi_flags |= BCH_INODE_unlinked;
 	}
 }
 
diff --git a/libbcachefs/io_write.c b/libbcachefs/io_write.c
index 613f3843..fbfc42ff 100644
--- a/libbcachefs/io_write.c
+++ b/libbcachefs/io_write.c
@@ -223,7 +223,7 @@ static inline int bch2_extent_update_i_size_sectors(struct btree_trans *trans,
 
 	inode = bkey_i_to_inode_v3(k);
 
-	if (!(le64_to_cpu(inode->v.bi_flags) & BCH_INODE_I_SIZE_DIRTY) &&
+	if (!(le64_to_cpu(inode->v.bi_flags) & BCH_INODE_i_size_dirty) &&
 	    new_i_size > le64_to_cpu(inode->v.bi_size)) {
 		inode->v.bi_size = cpu_to_le64(new_i_size);
 		inode_update_flags = 0;
diff --git a/libbcachefs/move.c b/libbcachefs/move.c
index 1b15b010..ab749bf2 100644
--- a/libbcachefs/move.c
+++ b/libbcachefs/move.c
@@ -147,9 +147,8 @@ void bch2_moving_ctxt_do_pending_writes(struct moving_context *ctxt)
 {
 	struct moving_io *io;
 
-	bch2_trans_unlock(ctxt->trans);
-
 	while ((io = bch2_moving_ctxt_next_pending_write(ctxt))) {
+		bch2_trans_unlock_long(ctxt->trans);
 		list_del(&io->read_list);
 		move_write(io);
 	}
@@ -485,8 +484,8 @@ int bch2_move_ratelimit(struct moving_context *ctxt)
 	struct bch_fs *c = ctxt->trans->c;
 	u64 delay;
 
-	if (ctxt->wait_on_copygc) {
-		bch2_trans_unlock(ctxt->trans);
+	if (ctxt->wait_on_copygc && !c->copygc_running) {
+		bch2_trans_unlock_long(ctxt->trans);
 		wait_event_killable(c->copygc_running_wq,
 				    !c->copygc_running ||
 				    kthread_should_stop());
@@ -495,8 +494,12 @@ int bch2_move_ratelimit(struct moving_context *ctxt)
 	do {
 		delay = ctxt->rate ? bch2_ratelimit_delay(ctxt->rate) : 0;
 
+
 		if (delay) {
-			bch2_trans_unlock(ctxt->trans);
+			if (delay > HZ / 10)
+				bch2_trans_unlock_long(ctxt->trans);
+			else
+				bch2_trans_unlock(ctxt->trans);
 			set_current_state(TASK_INTERRUPTIBLE);
 		}
 
diff --git a/libbcachefs/move.h b/libbcachefs/move.h
index 1b1e8678..07cf9d42 100644
--- a/libbcachefs/move.h
+++ b/libbcachefs/move.h
@@ -45,6 +45,7 @@ do {									\
 									\
 	if (_cond)							\
 		break;							\
+	bch2_trans_unlock_long((_ctxt)->trans);				\
 	__wait_event((_ctxt)->wait,					\
 		     bch2_moving_ctxt_next_pending_write(_ctxt) ||	\
 		     (cond_finished = (_cond)));			\
diff --git a/libbcachefs/movinggc.c b/libbcachefs/movinggc.c
index f73b9b7f..0158c7aa 100644
--- a/libbcachefs/movinggc.c
+++ b/libbcachefs/movinggc.c
@@ -128,7 +128,7 @@ static void move_buckets_wait(struct moving_context *ctxt,
 		kfree(i);
 	}
 
-	bch2_trans_unlock(ctxt->trans);
+	bch2_trans_unlock_long(ctxt->trans);
 }
 
 static bool bucket_in_flight(struct buckets_in_flight *list,
@@ -188,7 +188,8 @@ static int bch2_copygc_get_buckets(struct moving_context *ctxt,
 
 noinline
 static int bch2_copygc(struct moving_context *ctxt,
-		       struct buckets_in_flight *buckets_in_flight)
+		       struct buckets_in_flight *buckets_in_flight,
+		       bool *did_work)
 {
 	struct btree_trans *trans = ctxt->trans;
 	struct bch_fs *c = trans->c;
@@ -224,6 +225,8 @@ static int bch2_copygc(struct moving_context *ctxt,
 					     f->bucket.k.gen, data_opts);
 		if (ret)
 			goto err;
+
+		*did_work = true;
 	}
 err:
 	darray_exit(&buckets);
@@ -302,14 +305,16 @@ static int bch2_copygc_thread(void *arg)
 	struct moving_context ctxt;
 	struct bch_move_stats move_stats;
 	struct io_clock *clock = &c->io_clock[WRITE];
-	struct buckets_in_flight buckets;
+	struct buckets_in_flight *buckets;
 	u64 last, wait;
 	int ret = 0;
 
-	memset(&buckets, 0, sizeof(buckets));
-
-	ret = rhashtable_init(&buckets.table, &bch_move_bucket_params);
+	buckets = kzalloc(sizeof(struct buckets_in_flight), GFP_KERNEL);
+	if (!buckets)
+		return -ENOMEM;
+	ret = rhashtable_init(&buckets->table, &bch_move_bucket_params);
 	if (ret) {
+		kfree(buckets);
 		bch_err_msg(c, ret, "allocating copygc buckets in flight");
 		return ret;
 	}
@@ -322,16 +327,18 @@ static int bch2_copygc_thread(void *arg)
 			      false);
 
 	while (!ret && !kthread_should_stop()) {
-		bch2_trans_unlock(ctxt.trans);
+		bool did_work = false;
+
+		bch2_trans_unlock_long(ctxt.trans);
 		cond_resched();
 
 		if (!c->copy_gc_enabled) {
-			move_buckets_wait(&ctxt, &buckets, true);
+			move_buckets_wait(&ctxt, buckets, true);
 			kthread_wait_freezable(c->copy_gc_enabled);
 		}
 
 		if (unlikely(freezing(current))) {
-			move_buckets_wait(&ctxt, &buckets, true);
+			move_buckets_wait(&ctxt, buckets, true);
 			__refrigerator(false);
 			continue;
 		}
@@ -342,7 +349,7 @@ static int bch2_copygc_thread(void *arg)
 		if (wait > clock->max_slop) {
 			c->copygc_wait_at = last;
 			c->copygc_wait = last + wait;
-			move_buckets_wait(&ctxt, &buckets, true);
+			move_buckets_wait(&ctxt, buckets, true);
 			trace_and_count(c, copygc_wait, c, wait, last + wait);
 			bch2_kthread_io_clock_wait(clock, last + wait,
 					MAX_SCHEDULE_TIMEOUT);
@@ -352,14 +359,26 @@ static int bch2_copygc_thread(void *arg)
 		c->copygc_wait = 0;
 
 		c->copygc_running = true;
-		ret = bch2_copygc(&ctxt, &buckets);
+		ret = bch2_copygc(&ctxt, buckets, &did_work);
 		c->copygc_running = false;
 
 		wake_up(&c->copygc_running_wq);
+
+		if (!wait && !did_work) {
+			u64 min_member_capacity = bch2_min_rw_member_capacity(c);
+
+			if (min_member_capacity == U64_MAX)
+				min_member_capacity = 128 * 2048;
+
+			bch2_kthread_io_clock_wait(clock, last + (min_member_capacity >> 6),
+					MAX_SCHEDULE_TIMEOUT);
+		}
 	}
 
-	move_buckets_wait(&ctxt, &buckets, true);
-	rhashtable_destroy(&buckets.table);
+	move_buckets_wait(&ctxt, buckets, true);
+
+	rhashtable_destroy(&buckets->table);
+	kfree(buckets);
 	bch2_moving_ctxt_exit(&ctxt);
 	bch2_move_stats_exit(&move_stats, c);
 
diff --git a/libbcachefs/rebalance.c b/libbcachefs/rebalance.c
index 6ee4d2e0..3319190b 100644
--- a/libbcachefs/rebalance.c
+++ b/libbcachefs/rebalance.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 
 #include "bcachefs.h"
+#include "alloc_background.h"
 #include "alloc_foreground.h"
 #include "btree_iter.h"
 #include "btree_update.h"
@@ -282,15 +283,12 @@ static int do_rebalance_scan(struct moving_context *ctxt, u64 inum, u64 cookie)
 static void rebalance_wait(struct bch_fs *c)
 {
 	struct bch_fs_rebalance *r = &c->rebalance;
-	struct bch_dev *ca;
 	struct io_clock *clock = &c->io_clock[WRITE];
 	u64 now = atomic64_read(&clock->now);
-	u64 min_member_capacity = 128 * 2048;
-	unsigned i;
+	u64 min_member_capacity = bch2_min_rw_member_capacity(c);
 
-	for_each_rw_member(ca, c, i)
-		min_member_capacity = min(min_member_capacity,
-					  ca->mi.nbuckets * ca->mi.bucket_size);
+	if (min_member_capacity == U64_MAX)
+		min_member_capacity = 128 * 2048;
 
 	r->wait_iotime_end		= now + (min_member_capacity >> 6);
 
@@ -350,7 +348,7 @@ static int do_rebalance(struct moving_context *ctxt)
 	    !kthread_should_stop() &&
 	    !atomic64_read(&r->work_stats.sectors_seen) &&
 	    !atomic64_read(&r->scan_stats.sectors_seen)) {
-		bch2_trans_unlock(trans);
+		bch2_trans_unlock_long(trans);
 		rebalance_wait(c);
 	}
 
diff --git a/libbcachefs/recovery.c b/libbcachefs/recovery.c
index f73338f3..9600b808 100644
--- a/libbcachefs/recovery.c
+++ b/libbcachefs/recovery.c
@@ -226,7 +226,7 @@ static int journal_replay_entry_early(struct bch_fs *c,
 
 		if (entry->u64s) {
 			r->level = entry->level;
-			bkey_copy(&r->key, &entry->start[0]);
+			bkey_copy(&r->key, (struct bkey_i *) entry->start);
 			r->error = 0;
 		} else {
 			r->error = -EIO;
diff --git a/libbcachefs/reflink.c b/libbcachefs/reflink.c
index eb31df60..6e1bfe9f 100644
--- a/libbcachefs/reflink.c
+++ b/libbcachefs/reflink.c
@@ -255,7 +255,7 @@ s64 bch2_remap_range(struct bch_fs *c,
 	struct bpos dst_end = dst_start, src_end = src_start;
 	struct bch_io_opts opts;
 	struct bpos src_want;
-	u64 dst_done;
+	u64 dst_done = 0;
 	u32 dst_snapshot, src_snapshot;
 	int ret = 0, ret2 = 0;
 
diff --git a/libbcachefs/sb-errors.c b/libbcachefs/sb-errors.c
index 3d66f15a..9215d414 100644
--- a/libbcachefs/sb-errors.c
+++ b/libbcachefs/sb-errors.c
@@ -61,7 +61,6 @@ static void bch2_sb_errors_to_text(struct printbuf *out, struct bch_sb *sb,
 {
 	struct bch_sb_field_errors *e = field_to_type(f, errors);
 	unsigned i, nr = bch2_sb_field_errors_nr_entries(e);
-	u64 now = ktime_get_real_seconds();
 
 	if (out->nr_tabstops <= 1)
 		printbuf_tabstop_push(out, 16);
@@ -71,9 +70,7 @@ static void bch2_sb_errors_to_text(struct printbuf *out, struct bch_sb *sb,
 		prt_tab(out);
 		prt_u64(out, BCH_SB_ERROR_ENTRY_NR(&e->entries[i]));
 		prt_tab(out);
-		bch2_pr_time_units(out, (now - le64_to_cpu(e->entries[i].last_error_time)) *
-				   NSEC_PER_SEC);
-		prt_str(out, " ago");
+		bch2_prt_date_seconds(out, le64_to_cpu(e->entries[i].last_error_time));
 		prt_newline(out);
 	}
 }
diff --git a/libbcachefs/sb-members.c b/libbcachefs/sb-members.c
index ab5de12e..6a7e20de 100644
--- a/libbcachefs/sb-members.c
+++ b/libbcachefs/sb-members.c
@@ -21,19 +21,14 @@ char * const bch2_member_error_strs[] = {
 
 /* Code for bch_sb_field_members_v1: */
 
-static struct bch_member *members_v2_get_mut(struct bch_sb_field_members_v2 *mi, int i)
-{
-	return (void *) mi->_members + (i * le16_to_cpu(mi->member_bytes));
-}
-
 struct bch_member *bch2_members_v2_get_mut(struct bch_sb *sb, int i)
 {
-	return members_v2_get_mut(bch2_sb_field_get(sb, members_v2), i);
+	return __bch2_members_v2_get_mut(bch2_sb_field_get(sb, members_v2), i);
 }
 
 static struct bch_member members_v2_get(struct bch_sb_field_members_v2 *mi, int i)
 {
-	struct bch_member ret, *p = members_v2_get_mut(mi, i);
+	struct bch_member ret, *p = __bch2_members_v2_get_mut(mi, i);
 	memset(&ret, 0, sizeof(ret));
 	memcpy(&ret, p, min_t(size_t, le16_to_cpu(mi->member_bytes), sizeof(ret)));
 	return ret;
@@ -75,7 +70,7 @@ static int sb_members_v2_resize_entries(struct bch_fs *c)
 
 		for (int i = c->disk_sb.sb->nr_devices - 1; i >= 0; --i) {
 			void *dst = (void *) mi->_members + (i * sizeof(struct bch_member));
-			memmove(dst, members_v2_get_mut(mi, i), le16_to_cpu(mi->member_bytes));
+			memmove(dst, __bch2_members_v2_get_mut(mi, i), le16_to_cpu(mi->member_bytes));
 			memset(dst + le16_to_cpu(mi->member_bytes),
 			       0, (sizeof(struct bch_member) - le16_to_cpu(mi->member_bytes)));
 		}
@@ -118,7 +113,7 @@ int bch2_sb_members_cpy_v2_v1(struct bch_sb_handle *disk_sb)
 	mi2 = bch2_sb_field_get(disk_sb->sb, members_v2);
 
 	for (unsigned i = 0; i < disk_sb->sb->nr_devices; i++)
-		memcpy(members_v1_get_mut(mi1, i), members_v2_get_mut(mi2, i), BCH_MEMBER_V1_BYTES);
+		memcpy(members_v1_get_mut(mi1, i), __bch2_members_v2_get_mut(mi2, i), BCH_MEMBER_V1_BYTES);
 
 	return 0;
 }
@@ -235,7 +230,7 @@ static void member_to_text(struct printbuf *out,
 	prt_printf(out, "Last mount:");
 	prt_tab(out);
 	if (m.last_mount)
-		pr_time(out, le64_to_cpu(m.last_mount));
+		bch2_prt_date_seconds(out, le64_to_cpu(m.last_mount));
 	else
 		prt_printf(out, "(never)");
 	prt_newline(out);
@@ -332,7 +327,7 @@ static int bch2_sb_members_v2_validate(struct bch_sb *sb,
 				       struct printbuf *err)
 {
 	struct bch_sb_field_members_v2 *mi = field_to_type(f, members_v2);
-	size_t mi_bytes = (void *) members_v2_get_mut(mi, sb->nr_devices) -
+	size_t mi_bytes = (void *) __bch2_members_v2_get_mut(mi, sb->nr_devices) -
 		(void *) mi;
 
 	if (mi_bytes > vstruct_bytes(&mi->field)) {
@@ -363,7 +358,7 @@ void bch2_sb_members_from_cpu(struct bch_fs *c)
 
 	rcu_read_lock();
 	for_each_member_device_rcu(ca, c, i, NULL) {
-		struct bch_member *m = members_v2_get_mut(mi, i);
+		struct bch_member *m = __bch2_members_v2_get_mut(mi, i);
 
 		for (e = 0; e < BCH_MEMBER_ERROR_NR; e++)
 			m->errors[e] = cpu_to_le64(atomic64_read(&ca->errors[e]));
diff --git a/libbcachefs/sb-members.h b/libbcachefs/sb-members.h
index 1583e80a..03613e3e 100644
--- a/libbcachefs/sb-members.h
+++ b/libbcachefs/sb-members.h
@@ -4,6 +4,12 @@
 
 extern char * const bch2_member_error_strs[];
 
+static inline struct bch_member *
+__bch2_members_v2_get_mut(struct bch_sb_field_members_v2 *mi, unsigned i)
+{
+	return (void *) mi->_members + (i * le16_to_cpu(mi->member_bytes));
+}
+
 int bch2_sb_members_v2_init(struct bch_fs *c);
 int bch2_sb_members_cpy_v2_v1(struct bch_sb_handle *disk_sb);
 struct bch_member *bch2_members_v2_get_mut(struct bch_sb *sb, int i);
@@ -186,11 +192,10 @@ static inline bool bch2_member_exists(struct bch_member *m)
 	return !bch2_is_zero(&m->uuid, sizeof(m->uuid));
 }
 
-static inline bool bch2_dev_exists(struct bch_sb *sb,
-				   unsigned dev)
+static inline bool bch2_dev_exists(struct bch_sb *sb, unsigned dev)
 {
 	if (dev < sb->nr_devices) {
-	struct bch_member m = bch2_sb_member_get(sb, dev);
+		struct bch_member m = bch2_sb_member_get(sb, dev);
 		return bch2_member_exists(&m);
 	}
 	return false;
diff --git a/libbcachefs/six.c b/libbcachefs/six.c
index 458a1de0..d22826ca 100644
--- a/libbcachefs/six.c
+++ b/libbcachefs/six.c
@@ -323,99 +323,55 @@ EXPORT_SYMBOL_GPL(six_relock_ip);
 
 #ifdef CONFIG_LOCK_SPIN_ON_OWNER
 
-static inline bool six_can_spin_on_owner(struct six_lock *lock)
+static inline bool six_owner_running(struct six_lock *lock)
 {
-	struct task_struct *owner;
-	bool ret;
-
-	if (need_resched())
-		return false;
-
+	/*
+	 * When there's no owner, we might have preempted between the owner
+	 * acquiring the lock and setting the owner field. If we're an RT task
+	 * that will live-lock because we won't let the owner complete.
+	 */
 	rcu_read_lock();
-	owner = READ_ONCE(lock->owner);
-	ret = !owner || owner_on_cpu(owner);
+	struct task_struct *owner = READ_ONCE(lock->owner);
+	bool ret = owner ? owner_on_cpu(owner) : !rt_task(current);
 	rcu_read_unlock();
 
 	return ret;
 }
 
-static inline bool six_spin_on_owner(struct six_lock *lock,
-				     struct task_struct *owner,
-				     u64 end_time)
+static inline bool six_optimistic_spin(struct six_lock *lock,
+				       struct six_lock_waiter *wait,
+				       enum six_lock_type type)
 {
-	bool ret = true;
 	unsigned loop = 0;
-
-	rcu_read_lock();
-	while (lock->owner == owner) {
-		/*
-		 * Ensure we emit the owner->on_cpu, dereference _after_
-		 * checking lock->owner still matches owner. If that fails,
-		 * owner might point to freed memory. If it still matches,
-		 * the rcu_read_lock() ensures the memory stays valid.
-		 */
-		barrier();
-
-		if (!owner_on_cpu(owner) || need_resched()) {
-			ret = false;
-			break;
-		}
-
-		if (!(++loop & 0xf) && (time_after64(sched_clock(), end_time))) {
-			six_set_bitmask(lock, SIX_LOCK_NOSPIN);
-			ret = false;
-			break;
-		}
-
-		cpu_relax();
-	}
-	rcu_read_unlock();
-
-	return ret;
-}
-
-static inline bool six_optimistic_spin(struct six_lock *lock, enum six_lock_type type)
-{
-	struct task_struct *task = current;
 	u64 end_time;
 
 	if (type == SIX_LOCK_write)
 		return false;
 
+	if (lock->wait_list.next != &wait->list)
+		return false;
+
+	if (atomic_read(&lock->state) & SIX_LOCK_NOSPIN)
+		return false;
+
 	preempt_disable();
-	if (!six_can_spin_on_owner(lock))
-		goto fail;
-
-	if (!osq_lock(&lock->osq))
-		goto fail;
-
 	end_time = sched_clock() + 10 * NSEC_PER_USEC;
 
-	while (1) {
-		struct task_struct *owner;
-
+	while (!need_resched() && six_owner_running(lock)) {
 		/*
-		 * If there's an owner, wait for it to either
-		 * release the lock or go to sleep.
+		 * Ensures that writes to the waitlist entry happen after we see
+		 * wait->lock_acquired: pairs with the smp_store_release in
+		 * __six_lock_wakeup
 		 */
-		owner = READ_ONCE(lock->owner);
-		if (owner && !six_spin_on_owner(lock, owner, end_time))
-			break;
-
-		if (do_six_trylock(lock, type, false)) {
-			osq_unlock(&lock->osq);
+		if (smp_load_acquire(&wait->lock_acquired)) {
 			preempt_enable();
 			return true;
 		}
 
-		/*
-		 * When there's no owner, we might have preempted between the
-		 * owner acquiring the lock and setting the owner field. If
-		 * we're an RT task that will live-lock because we won't let
-		 * the owner complete.
-		 */
-		if (!owner && (need_resched() || rt_task(task)))
+		if (!(++loop & 0xf) && (time_after64(sched_clock(), end_time))) {
+			six_set_bitmask(lock, SIX_LOCK_NOSPIN);
 			break;
+		}
 
 		/*
 		 * The cpu_relax() call is a compiler barrier which forces
@@ -426,24 +382,15 @@ static inline bool six_optimistic_spin(struct six_lock *lock, enum six_lock_type
 		cpu_relax();
 	}
 
-	osq_unlock(&lock->osq);
-fail:
 	preempt_enable();
-
-	/*
-	 * If we fell out of the spin path because of need_resched(),
-	 * reschedule now, before we try-lock again. This avoids getting
-	 * scheduled out right after we obtained the lock.
-	 */
-	if (need_resched())
-		schedule();
-
 	return false;
 }
 
 #else /* CONFIG_LOCK_SPIN_ON_OWNER */
 
-static inline bool six_optimistic_spin(struct six_lock *lock, enum six_lock_type type)
+static inline bool six_optimistic_spin(struct six_lock *lock,
+				       struct six_lock_waiter *wait,
+				       enum six_lock_type type)
 {
 	return false;
 }
@@ -467,9 +414,6 @@ static int six_lock_slowpath(struct six_lock *lock, enum six_lock_type type,
 	trace_contention_begin(lock, 0);
 	lock_contended(&lock->dep_map, ip);
 
-	if (six_optimistic_spin(lock, type))
-		goto out;
-
 	wait->task		= current;
 	wait->lock_want		= type;
 	wait->lock_acquired	= false;
@@ -507,6 +451,9 @@ static int six_lock_slowpath(struct six_lock *lock, enum six_lock_type type,
 		ret = 0;
 	}
 
+	if (six_optimistic_spin(lock, wait, type))
+		goto out;
+
 	while (1) {
 		set_current_state(TASK_UNINTERRUPTIBLE);
 
diff --git a/libbcachefs/six.h b/libbcachefs/six.h
index 394da423..a7104ac1 100644
--- a/libbcachefs/six.h
+++ b/libbcachefs/six.h
@@ -124,7 +124,6 @@
  */
 
 #include <linux/lockdep.h>
-#include <linux/osq_lock.h>
 #include <linux/sched.h>
 #include <linux/types.h>
 
@@ -140,7 +139,6 @@ struct six_lock {
 	unsigned		intent_lock_recurse;
 	struct task_struct	*owner;
 	unsigned __percpu	*readers;
-	struct optimistic_spin_queue osq;
 	raw_spinlock_t		wait_lock;
 	struct list_head	wait_list;
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
diff --git a/libbcachefs/super-io.c b/libbcachefs/super-io.c
index 83bdb436..a93e53d0 100644
--- a/libbcachefs/super-io.c
+++ b/libbcachefs/super-io.c
@@ -1183,7 +1183,7 @@ void bch2_sb_to_text(struct printbuf *out, struct bch_sb *sb,
 	prt_printf(out, "Created:");
 	prt_tab(out);
 	if (sb->time_base_lo)
-		pr_time(out, div_u64(le64_to_cpu(sb->time_base_lo), NSEC_PER_SEC));
+		bch2_prt_date_seconds(out, div_u64(le64_to_cpu(sb->time_base_lo), NSEC_PER_SEC));
 	else
 		prt_printf(out, "(not set)");
 	prt_newline(out);
diff --git a/libbcachefs/super.c b/libbcachefs/super.c
index 1b5c2a1b..24672bb3 100644
--- a/libbcachefs/super.c
+++ b/libbcachefs/super.c
@@ -1885,9 +1885,9 @@ found:
 struct bch_fs *bch2_fs_open(char * const *devices, unsigned nr_devices,
 			    struct bch_opts opts)
 {
-	struct bch_sb_handle *sb = NULL;
+	DARRAY(struct bch_sb_handle) sbs = { 0 };
 	struct bch_fs *c = NULL;
-	unsigned i, best_sb = 0;
+	struct bch_sb_handle *sb, *best = NULL;
 	struct printbuf errbuf = PRINTBUF;
 	int ret = 0;
 
@@ -1899,49 +1899,46 @@ struct bch_fs *bch2_fs_open(char * const *devices, unsigned nr_devices,
 		goto err;
 	}
 
-	sb = kcalloc(nr_devices, sizeof(*sb), GFP_KERNEL);
-	if (!sb) {
-		ret = -ENOMEM;
+	ret = darray_make_room(&sbs, nr_devices);
+	if (ret)
 		goto err;
-	}
 
-	for (i = 0; i < nr_devices; i++) {
-		ret = bch2_read_super(devices[i], &opts, &sb[i]);
+	for (unsigned i = 0; i < nr_devices; i++) {
+		struct bch_sb_handle sb = { NULL };
+
+		ret = bch2_read_super(devices[i], &opts, &sb);
 		if (ret)
 			goto err;
 
+		BUG_ON(darray_push(&sbs, sb));
 	}
 
-	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;
+	darray_for_each(sbs, sb)
+		if (!best || le64_to_cpu(sb->sb->seq) > le64_to_cpu(best->sb->seq))
+			best = sb;
 
-	i = 0;
-	while (i < nr_devices) {
-		if (i != best_sb &&
-		    !bch2_dev_exists(sb[best_sb].sb, sb[i].sb->dev_idx)) {
-			pr_info("%pg has been removed, skipping", sb[i].bdev);
-			bch2_free_super(&sb[i]);
-			array_remove_item(sb, nr_devices, i);
+	darray_for_each_reverse(sbs, sb) {
+		if (sb != best && !bch2_dev_exists(best->sb, sb->sb->dev_idx)) {
+			pr_info("%pg has been removed, skipping", sb->bdev);
+			bch2_free_super(sb);
+			darray_remove_item(&sbs, sb);
+			best -= best > sb;
 			continue;
 		}
 
-		ret = bch2_dev_in_fs(sb[best_sb].sb, sb[i].sb);
+		ret = bch2_dev_in_fs(best->sb, sb->sb);
 		if (ret)
 			goto err_print;
-		i++;
 	}
 
-	c = bch2_fs_alloc(sb[best_sb].sb, opts);
-	if (IS_ERR(c)) {
-		ret = PTR_ERR(c);
+	c = bch2_fs_alloc(best->sb, opts);
+	ret = PTR_ERR_OR_ZERO(c);
+	if (ret)
 		goto err;
-	}
 
 	down_write(&c->state_lock);
-	for (i = 0; i < nr_devices; i++) {
-		ret = bch2_dev_attach_bdev(c, &sb[i]);
+	darray_for_each(sbs, sb) {
+		ret = bch2_dev_attach_bdev(c, sb);
 		if (ret) {
 			up_write(&c->state_lock);
 			goto err;
@@ -1960,7 +1957,9 @@ struct bch_fs *bch2_fs_open(char * const *devices, unsigned nr_devices,
 			goto err;
 	}
 out:
-	kfree(sb);
+	darray_for_each(sbs, sb)
+		bch2_free_super(sb);
+	darray_exit(&sbs);
 	printbuf_exit(&errbuf);
 	module_put(THIS_MODULE);
 	return c;
@@ -1970,9 +1969,6 @@ err_print:
 err:
 	if (!IS_ERR_OR_NULL(c))
 		bch2_fs_stop(c);
-	if (sb)
-		for (i = 0; i < nr_devices; i++)
-			bch2_free_super(&sb[i]);
 	c = ERR_PTR(ret);
 	goto out;
 }
diff --git a/libbcachefs/util.c b/libbcachefs/util.c
index adeec805..7ba5df4e 100644
--- a/libbcachefs/util.c
+++ b/libbcachefs/util.c
@@ -467,6 +467,24 @@ static void bch2_pr_time_units_aligned(struct printbuf *out, u64 ns)
 	prt_printf(out, "%s", u->name);
 }
 
+#ifndef __KERNEL__
+#include <time.h>
+void bch2_prt_date_seconds(struct printbuf *out, time64_t sec)
+{
+	time_t t = sec;
+	char buf[64];
+	ctime_r(&t, buf);
+	prt_str(out, buf);
+}
+#else
+void bch2_prt_date_seconds(struct printbuf *out, time64_t sec)
+{
+	char buf[64];
+	snprintf(buf, sizeof(buf), "%ptT", &sec);
+	prt_u64(out, sec);
+}
+#endif
+
 #define TABSTOP_SIZE 12
 
 static inline void pr_name_and_units(struct printbuf *out, const char *name, u64 ns)
diff --git a/libbcachefs/util.h b/libbcachefs/util.h
index 67f1a1d2..0595605e 100644
--- a/libbcachefs/util.h
+++ b/libbcachefs/util.h
@@ -244,26 +244,7 @@ do {									\
 #define prt_bitflags(...)		bch2_prt_bitflags(__VA_ARGS__)
 
 void bch2_pr_time_units(struct printbuf *, u64);
-
-#ifdef __KERNEL__
-static inline void pr_time(struct printbuf *out, u64 time)
-{
-	prt_printf(out, "%llu", time);
-}
-#else
-#include <time.h>
-static inline void pr_time(struct printbuf *out, u64 _time)
-{
-	char time_str[64];
-	time_t time = _time;
-	struct tm *tm = localtime(&time);
-	size_t err = strftime(time_str, sizeof(time_str), "%c", tm);
-	if (!err)
-		prt_printf(out, "(formatting error)");
-	else
-		prt_printf(out, "%s", time_str);
-}
-#endif
+void bch2_prt_date_seconds(struct printbuf *, time64_t);
 
 #ifdef __KERNEL__
 static inline void uuid_unparse_lower(u8 *uuid, char *out)
diff --git a/linux/closure.c b/linux/closure.c
index 1faa24d6..f86c9eea 100644
--- a/linux/closure.c
+++ b/linux/closure.c
@@ -17,9 +17,8 @@ static inline void closure_put_after_sub(struct closure *cl, int flags)
 {
 	int r = flags & CLOSURE_REMAINING_MASK;
 
-	if ((flags & CLOSURE_GUARD_MASK) ||
-	    (!r && (flags & ~CLOSURE_DESTRUCTOR)))
-		panic("closure_put_after_sub: bogus flags %x remaining %i", flags, r);
+	BUG_ON(flags & CLOSURE_GUARD_MASK);
+	BUG_ON(!r && (flags & ~CLOSURE_DESTRUCTOR));
 
 	if (!r) {
 		smp_acquire__after_ctrl_dep();