6c3d329e64
We used to (ab)use the DMA ops for setting up identical mappings in the IOTLB. This patch tries to get rid of the those unnecessary DMA ops by maintaining a simple identical/passthrough mappings by default. When bound to virtio_vdpa driver, DMA API will simply use PA as the IOVA and we will be all fine. When the vDPA bus tries to setup customized mapping (e.g when bound to vhost-vDPA), the identical/passthrough mapping will be removed. Signed-off-by: Jason Wang <jasowang@redhat.com> Message-Id: <20221223060021.28011-1-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Christoph Hellwig <hch@lst.de>