vDPA/ifcvf: deduce VIRTIO device ID from pdev ids

This commit deduces the VIRTIO device ID of a probed
device from its pdev device ids.
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Link: https://lore.kernel.org/r/20210317094933.16417-8-lingshan.zhu@intel.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>

drivers/vdpa/ifcvf/ifcvf_base.h

@@ -127,4 +127,5 @@ int ifcvf_verify_min_features(struct ifcvf_hw *hw, u64 features);
 u16 ifcvf_get_vq_state(struct ifcvf_hw *hw, u16 qid);
 int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u16 num);
 struct ifcvf_adapter *vf_to_adapter(struct ifcvf_hw *hw);
+int ifcvf_probed_virtio_net(struct ifcvf_hw *hw);
 #endif /* _IFCVF_H_ */

drivers/vdpa/ifcvf/ifcvf_main.c

@@ -323,7 +323,19 @@ static u32 ifcvf_vdpa_get_generation(struct vdpa_device *vdpa_dev)
 
 static u32 ifcvf_vdpa_get_device_id(struct vdpa_device *vdpa_dev)
 {
-	return VIRTIO_ID_NET;
+	struct ifcvf_adapter *adapter = vdpa_to_adapter(vdpa_dev);
+	struct pci_dev *pdev = adapter->pdev;
+	u32 ret = -ENODEV;
+
+	if (pdev->device < 0x1000 || pdev->device > 0x107f)
+		return ret;
+
+	if (pdev->device < 0x1040)
+		ret =  pdev->subsystem_device;
+	else
+		ret =  pdev->device - 0x1040;
+
+	return ret;
 }
 
 static u32 ifcvf_vdpa_get_vendor_id(struct vdpa_device *vdpa_dev)