1 files changed, 55 insertions, 27 deletions

diff --git a/libbcachefs/btree_update_interior.c b/libbcachefs/btree_update_interior.c
index a0f37c4c..e92a6a3a 100644
--- a/libbcachefs/btree_update_interior.c
+++ b/libbcachefs/btree_update_interior.c
@@ -270,6 +270,17 @@ void bch2_btree_node_free_never_inserted(struct bch_fs *c, struct btree *b)
 void bch2_btree_node_free_inmem(struct bch_fs *c, struct btree *b,
 				struct btree_iter *iter)
 {
+	/*
+	 * Is this a node that isn't reachable on disk yet?
+	 *
+	 * Nodes that aren't reachable yet have writes blocked until they're
+	 * reachable - now that we've cancelled any pending writes and moved
+	 * things waiting on that write to wait on this update, we can drop this
+	 * node from the list of nodes that the other update is making
+	 * reachable, prior to freeing it:
+	 */
+	btree_update_drop_new_node(c, b);
+
 	bch2_btree_iter_node_drop_linked(iter, b);
 
 	__btree_node_free(c, b, iter);
@@ -503,8 +514,7 @@ static struct btree_reserve *bch2_btree_reserve_get(struct bch_fs *c,
 	struct btree *b;
 	struct disk_reservation disk_res = { 0, 0 };
 	unsigned sectors = nr_nodes * c->opts.btree_node_size;
-	int ret, disk_res_flags = BCH_DISK_RESERVATION_GC_LOCK_HELD|
-		BCH_DISK_RESERVATION_METADATA;
+	int ret, disk_res_flags = BCH_DISK_RESERVATION_GC_LOCK_HELD;
 
 	if (flags & BTREE_INSERT_NOFAIL)
 		disk_res_flags |= BCH_DISK_RESERVATION_NOFAIL;
@@ -517,7 +527,9 @@ static struct btree_reserve *bch2_btree_reserve_get(struct bch_fs *c,
 	if (ret)
 		return ERR_PTR(ret);
 
-	if (bch2_disk_reservation_get(c, &disk_res, sectors, disk_res_flags))
+	if (bch2_disk_reservation_get(c, &disk_res, sectors,
+				      c->opts.metadata_replicas,
+				      disk_res_flags))
 		return ERR_PTR(-ENOSPC);
 
 	BUG_ON(nr_nodes > BTREE_RESERVE_MAX);
@@ -597,12 +609,17 @@ static void btree_update_nodes_reachable(struct closure *cl)
 	while (as->nr_new_nodes) {
 		struct btree *b = as->new_nodes[--as->nr_new_nodes];
 
-		BUG_ON(b->will_make_reachable != as);
-		b->will_make_reachable = NULL;
+		BUG_ON(b->will_make_reachable &&
+		       (struct btree_update *) b->will_make_reachable != as);
+		b->will_make_reachable = 0;
 		mutex_unlock(&c->btree_interior_update_lock);
 
+		/*
+		 * b->will_make_reachable prevented it from being written, so
+		 * write it now if it needs to be written:
+		 */
 		six_lock_read(&b->lock);
-		bch2_btree_node_write_dirty(c, b, NULL, btree_node_need_write(b));
+		bch2_btree_node_write_cond(c, b, btree_node_need_write(b));
 		six_unlock_read(&b->lock);
 		mutex_lock(&c->btree_interior_update_lock);
 	}
@@ -651,8 +668,11 @@ retry:
 		list_del(&as->write_blocked_list);
 		mutex_unlock(&c->btree_interior_update_lock);
 
-		bch2_btree_node_write_dirty(c, b, NULL,
-					    btree_node_need_write(b));
+		/*
+		 * b->write_blocked prevented it from being written, so
+		 * write it now if it needs to be written:
+		 */
+		bch2_btree_node_write_cond(c, b, btree_node_need_write(b));
 		six_unlock_read(&b->lock);
 		break;
 
@@ -851,17 +871,25 @@ static void btree_node_will_make_reachable(struct btree_update *as,
 	BUG_ON(b->will_make_reachable);
 
 	as->new_nodes[as->nr_new_nodes++] = b;
-	b->will_make_reachable = as;
+	b->will_make_reachable = 1UL|(unsigned long) as;
+
+	closure_get(&as->cl);
 	mutex_unlock(&c->btree_interior_update_lock);
 }
 
-static void __btree_interior_update_drop_new_node(struct btree *b)
+static void btree_update_drop_new_node(struct bch_fs *c, struct btree *b)
 {
-	struct btree_update *as = b->will_make_reachable;
+	struct btree_update *as;
+	unsigned long v;
 	unsigned i;
 
-	BUG_ON(!as);
+	if (!b->will_make_reachable)
+		return;
+
+	mutex_lock(&c->btree_interior_update_lock);
+	v = xchg(&b->will_make_reachable, 0);
 
+	as = (struct btree_update *) (v & ~1UL);
 	for (i = 0; i < as->nr_new_nodes; i++)
 		if (as->new_nodes[i] == b)
 			goto found;
@@ -869,14 +897,10 @@ static void __btree_interior_update_drop_new_node(struct btree *b)
 	BUG();
 found:
 	array_remove_item(as->new_nodes, as->nr_new_nodes, i);
-	b->will_make_reachable = NULL;
-}
-
-static void btree_update_drop_new_node(struct bch_fs *c, struct btree *b)
-{
-	mutex_lock(&c->btree_interior_update_lock);
-	__btree_interior_update_drop_new_node(b);
 	mutex_unlock(&c->btree_interior_update_lock);
+
+	if (v & 1)
+		closure_put(&as->cl);
 }
 
 static void btree_interior_update_add_node_reference(struct btree_update *as,
@@ -952,6 +976,12 @@ void bch2_btree_interior_update_will_free_node(struct btree_update *as,
 	clear_btree_node_need_write(b);
 	w = btree_current_write(b);
 
+	/*
+	 * Does this node have any btree_update operations waiting on this node
+	 * to be written?
+	 *
+	 * If so, wake them up when this btree_update operation is reachable:
+	 */
 	llist_for_each_entry_safe(cl, cl_n, llist_del_all(&w->wait.list), list)
 		llist_add(&cl->list, &as->wait.list);
 
@@ -972,9 +1002,6 @@ void bch2_btree_interior_update_will_free_node(struct btree_update *as,
 				      &as->journal, interior_update_flush);
 	bch2_journal_pin_drop(&c->journal, &w->journal);
 
-	if (b->will_make_reachable)
-		__btree_interior_update_drop_new_node(b);
-
 	mutex_unlock(&c->btree_interior_update_lock);
 }
 
@@ -1338,7 +1365,7 @@ static void btree_split(struct btree_update *as, struct btree *b,
 		six_unlock_write(&n2->lock);
 		six_unlock_write(&n1->lock);
 
-		bch2_btree_node_write(c, n2, &as->cl, SIX_LOCK_intent);
+		bch2_btree_node_write(c, n2, SIX_LOCK_intent);
 
 		/*
 		 * Note that on recursive parent_keys == keys, so we
@@ -1356,7 +1383,8 @@ static void btree_split(struct btree_update *as, struct btree *b,
 			n3->sib_u64s[1] = U16_MAX;
 
 			btree_split_insert_keys(as, n3, iter, &as->parent_keys);
-			bch2_btree_node_write(c, n3, &as->cl, SIX_LOCK_intent);
+
+			bch2_btree_node_write(c, n3, SIX_LOCK_intent);
 		}
 	} else {
 		trace_btree_compact(c, b);
@@ -1367,7 +1395,7 @@ static void btree_split(struct btree_update *as, struct btree *b,
 		bch2_keylist_add(&as->parent_keys, &n1->key);
 	}
 
-	bch2_btree_node_write(c, n1, &as->cl, SIX_LOCK_intent);
+	bch2_btree_node_write(c, n1, SIX_LOCK_intent);
 
 	/* New nodes all written, now make them visible: */
 
@@ -1668,7 +1696,7 @@ retry:
 	bch2_keylist_add(&as->parent_keys, &delete);
 	bch2_keylist_add(&as->parent_keys, &n->key);
 
-	bch2_btree_node_write(c, n, &as->cl, SIX_LOCK_intent);
+	bch2_btree_node_write(c, n, SIX_LOCK_intent);
 
 	bch2_btree_insert_node(as, parent, iter, &as->parent_keys);
 
@@ -1726,7 +1754,7 @@ static int __btree_node_rewrite(struct bch_fs *c, struct btree_iter *iter,
 
 	trace_btree_gc_rewrite_node(c, b);
 
-	bch2_btree_node_write(c, n, &as->cl, SIX_LOCK_intent);
+	bch2_btree_node_write(c, n, SIX_LOCK_intent);
 
 	if (parent) {
 		bch2_btree_insert_node(as, parent, iter,