diff --git a/mt76.h b/mt76.h
index 2cbea731..7f3ec403 100644
--- a/mt76.h
+++ b/mt76.h
@@ -166,8 +166,8 @@ enum mt76_dfs_state {
 
 struct mt76_queue_buf {
 	dma_addr_t addr;
-	u16 len;
-	bool skip_unmap;
+	u16 len:15,
+	    skip_unmap:1;
 };
 
 struct mt76_tx_info {