+#include "qemu/iov.h"
+
+void virtio_9p_push_and_notify(V9fsPDU *pdu)
+{
+ V9fsState *s = pdu->s;
+ V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
+ VirtQueueElement *elem = v->elems[pdu->idx];
+
+ /* push onto queue and notify */
+ virtqueue_push(v->vq, elem, pdu->size);
+ g_free(elem);
+ v->elems[pdu->idx] = NULL;
+
+ /* FIXME: we should batch these completions */
+ virtio_notify(VIRTIO_DEVICE(v), v->vq);
+}
+
+static void handle_9p_output(VirtIODevice *vdev, VirtQueue *vq)
+{
+ V9fsVirtioState *v = (V9fsVirtioState *)vdev;
+ V9fsState *s = &v->state;
+ V9fsPDU *pdu;
+ ssize_t len;
+
+ while ((pdu = pdu_alloc(s))) {
+ struct {
+ uint32_t size_le;
+ uint8_t id;
+ uint16_t tag_le;
+ } QEMU_PACKED out;
+ VirtQueueElement *elem;
+
+ elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
+ if (!elem) {
+ pdu_free(pdu);
+ break;
+ }
+
+ BUG_ON(elem->out_num == 0 || elem->in_num == 0);
+ QEMU_BUILD_BUG_ON(sizeof out != 7);
+
+ v->elems[pdu->idx] = elem;
+ len = iov_to_buf(elem->out_sg, elem->out_num, 0,
+ &out, sizeof out);
+ BUG_ON(len != sizeof out);
+
+ pdu->size = le32_to_cpu(out.size_le);
+
+ pdu->id = out.id;
+ pdu->tag = le16_to_cpu(out.tag_le);
+
+ qemu_co_queue_init(&pdu->complete);
+ pdu_submit(pdu);
+ }
+}