1 files changed, 40 insertions, 3 deletions

diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
index c76ebb531212..7b4a6396c553 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa.c
+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -210,13 +210,49 @@ static int vp_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 qid,
 	return -EOPNOTSUPP;
 }
 
+static int vp_vdpa_set_vq_state_split(struct vdpa_device *vdpa,
+				      const struct vdpa_vq_state *state)
+{
+	const struct vdpa_vq_state_split *split = &state->split;
+
+	if (split->avail_index == 0)
+		return 0;
+
+	return -EOPNOTSUPP;
+}
+
+static int vp_vdpa_set_vq_state_packed(struct vdpa_device *vdpa,
+				       const struct vdpa_vq_state *state)
+{
+	const struct vdpa_vq_state_packed *packed = &state->packed;
+
+	if (packed->last_avail_counter == 1 &&
+	    packed->last_avail_idx == 0 &&
+	    packed->last_used_counter == 1 &&
+	    packed->last_used_idx == 0)
+		return 0;
+
+	return -EOPNOTSUPP;
+}
+
 static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
 				const struct vdpa_vq_state *state)
 {
-	/* Note that this is not supported by virtio specification, so
-	 * we return -ENOPOTSUPP here. This means we can't support live
-	 * migration, vhost device start/stop.
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	/* Note that this is not supported by virtio specification.
+	 * But if the state is by chance equal to the device initial
+	 * state, we can let it go.
 	 */
+	if ((vp_modern_get_status(mdev) & VIRTIO_CONFIG_S_FEATURES_OK) &&
+	    !vp_modern_get_queue_enable(mdev, qid)) {
+		if (vp_modern_get_driver_features(mdev) &
+		    BIT_ULL(VIRTIO_F_RING_PACKED))
+			return vp_vdpa_set_vq_state_packed(vdpa, state);
+		else
+			return vp_vdpa_set_vq_state_split(vdpa,	state);
+	}
+
 	return -EOPNOTSUPP;
 }
 
@@ -442,6 +478,7 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 			vp_modern_map_vq_notify(mdev, i,
 						&vp_vdpa->vring[i].notify_pa);
 		if (!vp_vdpa->vring[i].notify) {
+			ret = -EINVAL;
 			dev_warn(&pdev->dev, "Fail to map vq notify %d\n", i);
 			goto err;
 		}