+static struct virtio_pmd_ctrl *
+virtio_send_command_packed(struct virtnet_ctl *cvq,
+ struct virtio_pmd_ctrl *ctrl,
+ int *dlen, int pkt_num)
+{
+ struct virtqueue *vq = cvq->vq;
+ int head;
+ struct vring_packed_desc *desc = vq->ring_packed.desc_packed;
+ struct virtio_pmd_ctrl *result;
+ bool avail_wrap_counter;
+ int sum = 0;
+ int nb_descs = 0;
+ int k;
+
+ /*
+ * Format is enforced in qemu code:
+ * One TX packet for header;
+ * At least one TX packet per argument;
+ * One RX packet for ACK.
+ */
+ head = vq->vq_avail_idx;
+ avail_wrap_counter = vq->avail_wrap_counter;
+ desc[head].addr = cvq->virtio_net_hdr_mem;
+ desc[head].len = sizeof(struct virtio_net_ctrl_hdr);
+ vq->vq_free_cnt--;
+ nb_descs++;
+ if (++vq->vq_avail_idx >= vq->vq_nentries) {
+ vq->vq_avail_idx -= vq->vq_nentries;
+ vq->avail_wrap_counter ^= 1;
+ }
+
+ for (k = 0; k < pkt_num; k++) {
+ desc[vq->vq_avail_idx].addr = cvq->virtio_net_hdr_mem
+ + sizeof(struct virtio_net_ctrl_hdr)
+ + sizeof(ctrl->status) + sizeof(uint8_t) * sum;
+ desc[vq->vq_avail_idx].len = dlen[k];
+ desc[vq->vq_avail_idx].flags = VRING_DESC_F_NEXT |
+ VRING_DESC_F_AVAIL(vq->avail_wrap_counter) |
+ VRING_DESC_F_USED(!vq->avail_wrap_counter);
+ sum += dlen[k];
+ vq->vq_free_cnt--;
+ nb_descs++;
+ if (++vq->vq_avail_idx >= vq->vq_nentries) {
+ vq->vq_avail_idx -= vq->vq_nentries;
+ vq->avail_wrap_counter ^= 1;
+ }
+ }
+
+ desc[vq->vq_avail_idx].addr = cvq->virtio_net_hdr_mem
+ + sizeof(struct virtio_net_ctrl_hdr);
+ desc[vq->vq_avail_idx].len = sizeof(ctrl->status);
+ desc[vq->vq_avail_idx].flags = VRING_DESC_F_WRITE |
+ VRING_DESC_F_AVAIL(vq->avail_wrap_counter) |
+ VRING_DESC_F_USED(!vq->avail_wrap_counter);
+ vq->vq_free_cnt--;
+ nb_descs++;
+ if (++vq->vq_avail_idx >= vq->vq_nentries) {
+ vq->vq_avail_idx -= vq->vq_nentries;
+ vq->avail_wrap_counter ^= 1;
+ }
+
+ virtio_wmb(vq->hw->weak_barriers);
+ desc[head].flags = VRING_DESC_F_NEXT |
+ VRING_DESC_F_AVAIL(avail_wrap_counter) |
+ VRING_DESC_F_USED(!avail_wrap_counter);
+
+ virtio_wmb(vq->hw->weak_barriers);
+ virtqueue_notify(vq);
+
+ /* wait for used descriptors in virtqueue */
+ while (!desc_is_used(&desc[head], vq))
+ usleep(100);
+
+ virtio_rmb(vq->hw->weak_barriers);
+
+ /* now get used descriptors */
+ vq->vq_free_cnt += nb_descs;
+ vq->vq_used_cons_idx += nb_descs;
+ if (vq->vq_used_cons_idx >= vq->vq_nentries) {
+ vq->vq_used_cons_idx -= vq->vq_nentries;
+ vq->used_wrap_counter ^= 1;
+ }
+
+ PMD_INIT_LOG(DEBUG, "vq->vq_free_cnt=%d\n"
+ "vq->vq_avail_idx=%d\n"
+ "vq->vq_used_cons_idx=%d\n"
+ "vq->avail_wrap_counter=%d\n"
+ "vq->used_wrap_counter=%d\n",
+ vq->vq_free_cnt,
+ vq->vq_avail_idx,
+ vq->vq_used_cons_idx,
+ vq->avail_wrap_counter,
+ vq->used_wrap_counter);
+
+ result = cvq->virtio_net_hdr_mz->addr;
+ return result;
+}
+