vhost_vdpa: support PACKED when setting-getting vring_base

Use the right structs for PACKED or split vqs when setting and
getting the vring base.

Fixes: 4c8cf31 ("vhost: introduce vDPA-based backend")
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Message-Id: <20230424225031.18947-4-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>

Author: emusln

drivers/vhost/vdpa.c

@@ -607,7 +607,14 @@ static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
 		if (r)
 			return r;
 
-		vq->last_avail_idx = vq_state.split.avail_index;
+		if (vhost_has_feature(vq, VIRTIO_F_RING_PACKED)) {
+			vq->last_avail_idx = vq_state.packed.last_avail_idx |
+					     (vq_state.packed.last_avail_counter << 15);
+			vq->last_used_idx = vq_state.packed.last_used_idx |
+					    (vq_state.packed.last_used_counter << 15);
+		} else {
+			vq->last_avail_idx = vq_state.split.avail_index;
+		}
 		break;
 	}
 
@@ -625,9 +632,15 @@ static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
 		break;
 
 	case VHOST_SET_VRING_BASE:
-		vq_state.split.avail_index = vq->last_avail_idx;
-		if (ops->set_vq_state(vdpa, idx, &vq_state))
-			r = -EINVAL;
+		if (vhost_has_feature(vq, VIRTIO_F_RING_PACKED)) {
+			vq_state.packed.last_avail_idx = vq->last_avail_idx & 0x7fff;
+			vq_state.packed.last_avail_counter = !!(vq->last_avail_idx & 0x8000);
+			vq_state.packed.last_used_idx = vq->last_used_idx & 0x7fff;
+			vq_state.packed.last_used_counter = !!(vq->last_used_idx & 0x8000);
+		} else {
+			vq_state.split.avail_index = vq->last_avail_idx;
+		}
+		r = ops->set_vq_state(vdpa, idx, &vq_state);
 		break;
 
 	case VHOST_SET_VRING_CALL: