d3f1f940eb
Spec said: "and len the total of bytes written into the buffer." For inflateq, deflateq and statsq, we don't process in_sg so the used length should be zero. For free_page_vq, tough the pages could be changed by the device (in the destination), spec said: "Note: len is particularly useful for drivers using untrusted buffers: if a driver does not know exactly how much has been written by the device, the driver would have to zero the buffer in advance to ensure no data leakage occurs." So 0 should be used as well here. Signed-off-by: Jason Wang <jasowang@redhat.com> Message-Id: <20211129030841.3611-2-jasowang@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com>