C++ (Cpp) vhost_net_tx_err Examples

Example #1

File: net.c Project: 383530895/linux

/* In case of DMA done not in order in lower device driver for some reason.
 * upend_idx is used to track end of used idx, done_idx is used to track head
 * of used idx. Once lower device DMA done contiguously, we will signal KVM
 * guest used idx.
 */
static void vhost_zerocopy_signal_used(struct vhost_net *net,
				       struct vhost_virtqueue *vq)
{
	struct vhost_net_virtqueue *nvq =
		container_of(vq, struct vhost_net_virtqueue, vq);
	int i, add;
	int j = 0;

	for (i = nvq->done_idx; i != nvq->upend_idx; i = (i + 1) % UIO_MAXIOV) {
		if (vq->heads[i].len == VHOST_DMA_FAILED_LEN)
			vhost_net_tx_err(net);
		if (VHOST_DMA_IS_DONE(vq->heads[i].len)) {
			vq->heads[i].len = VHOST_DMA_CLEAR_LEN;
			++j;
		} else
			break;
	}
	while (j) {
		add = min(UIO_MAXIOV - nvq->done_idx, j);
		vhost_add_used_and_signal_n(vq->dev, vq,
					    &vq->heads[nvq->done_idx], add);
		nvq->done_idx = (nvq->done_idx + add) % UIO_MAXIOV;
		j -= add;
	}
}

Example #2

File: net.c Project: AdrianHuang/linux-3.8.13

/* In case of DMA done not in order in lower device driver for some reason.
 * upend_idx is used to track end of used idx, done_idx is used to track head
 * of used idx. Once lower device DMA done contiguously, we will signal KVM
 * guest used idx.
 */
static int vhost_zerocopy_signal_used(struct vhost_net *net,
				      struct vhost_virtqueue *vq)
{
	int i;
	int j = 0;

	for (i = vq->done_idx; i != vq->upend_idx; i = (i + 1) % UIO_MAXIOV) {
		if (vq->heads[i].len == VHOST_DMA_FAILED_LEN)
			vhost_net_tx_err(net);
		if (VHOST_DMA_IS_DONE(vq->heads[i].len)) {
			vq->heads[i].len = VHOST_DMA_CLEAR_LEN;
			vhost_add_used_and_signal(vq->dev, vq,
						  vq->heads[i].id, 0);
			++j;
		} else
			break;
	}
	if (j)
		vq->done_idx = i;
	return j;
}