diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c index 9145e0624565..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; }