diff --git a/libpoke/ios.c b/libpoke/ios.c
index 0b7d8369..3471336e 100644
--- a/libpoke/ios.c
+++ b/libpoke/ios.c
@@ -1521,5 +1521,5 @@ ios_size (ios io)
 int
 ios_flush (ios io, ios_off offset)
 {
-  return io->dev_if->flush (io->dev, offset);
+  return io->dev_if->flush (io->dev, offset / 8);
 }