bcachefs: Fix btree path sorting

In btree_update_interior.c, we were changing a path's level directly -
which affects path sort order - without re-sorting paths, leading to
assertions when bch2_path_get() verified paths were sorted correctly.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

fs/bcachefs/btree_iter.c

@@ -1797,11 +1797,12 @@ void bch2_dump_trans_paths_updates(struct btree_trans *trans)
 
 		bch2_bpos_to_text(&buf1, path->pos);
 
-		printk(KERN_ERR "path: idx %u ref %u:%u%s%s btree %s pos %s locks %u %pS\n",
+		printk(KERN_ERR "path: idx %u ref %u:%u%s%s btree=%s l=%u pos %s locks %u %pS\n",
 		       path->idx, path->ref, path->intent_ref,
 		       path->should_be_locked ? " S" : "",
 		       path->preserve ? " P" : "",
 		       bch2_btree_ids[path->btree_id],
+		       path->level,
 		       buf1.buf,
 		       path->nodes_locked,
 #ifdef CONFIG_BCACHEFS_DEBUG

fs/bcachefs/btree_update_interior.c

@@ -1918,6 +1918,8 @@ static int __bch2_btree_node_update_key(struct btree_trans *trans,
 		path_l(iter2.path)->b = BTREE_ITER_NO_NODE_UP;
 		iter2.path->level++;
 
+		trans->paths_sorted = false;
+
 		ret   = bch2_btree_iter_traverse(&iter2) ?:
 			bch2_trans_update(trans, &iter2, new_key, BTREE_TRIGGER_NORUN);
 		if (ret)