static void handle_9p_output(VirtIODevice *vdev, VirtQueue *vq)
{
V9fsVirtioState *v = (V9fsVirtioState *)vdev;
V9fsState *s = &v->state;
V9fsPDU *pdu;
ssize_t len;
VirtQueueElement *elem;
while ((pdu = pdu_alloc(s))) {
struct {
uint32_t size_le;
uint8_t id;
uint16_t tag_le;
} QEMU_PACKED out;
elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
if (!elem) {
goto out_free_pdu;
}
if (elem->in_num == 0) {
virtio_error(vdev,
"The guest sent a VirtFS request without space for "
"the reply");
goto out_free_req;
}
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));
if (len != sizeof(out)) {
virtio_error(vdev, "The guest sent a malformed VirtFS request: "
"header size is %zd, should be 7", len);
goto out_free_req;
}
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);
}
return;
out_free_req:
virtqueue_detach_element(vq, elem, 0);
g_free(elem);
out_free_pdu:
pdu_free(pdu);
}
static void handle_9p_output(VirtIODevice *vdev, VirtQueue *vq)
{
V9fsVirtioState *v = (V9fsVirtioState *)vdev;
V9fsState *s = &v->state;
V9fsPDU *pdu;
ssize_t len;
VirtQueueElement *elem;
while ((pdu = pdu_alloc(s))) {
P9MsgHeader out;
elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
if (!elem) {
goto out_free_pdu;
}
if (elem->in_num == 0) {
virtio_error(vdev,
"The guest sent a VirtFS request without space for "
"the reply");
goto out_free_req;
}
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));
if (len != sizeof(out)) {
virtio_error(vdev, "The guest sent a malformed VirtFS request: "
"header size is %zd, should be 7", len);
goto out_free_req;
}
pdu_submit(pdu, &out);
}
return;
out_free_req:
virtqueue_detach_element(vq, elem, 0);
g_free(elem);
out_free_pdu:
pdu_free(pdu);
}
static int xen_9pfs_receive(Xen9pfsRing *ring)
{
P9MsgHeader h;
RING_IDX cons, prod, masked_prod, masked_cons, queued;
V9fsPDU *pdu;
if (ring->inprogress) {
return 0;
}
cons = ring->intf->out_cons;
prod = ring->intf->out_prod;
xen_rmb();
queued = xen_9pfs_queued(prod, cons, XEN_FLEX_RING_SIZE(ring->ring_order));
if (queued < sizeof(h)) {
return 0;
}
ring->inprogress = true;
masked_prod = xen_9pfs_mask(prod, XEN_FLEX_RING_SIZE(ring->ring_order));
masked_cons = xen_9pfs_mask(cons, XEN_FLEX_RING_SIZE(ring->ring_order));
xen_9pfs_read_packet((uint8_t *) &h, ring->ring.out, sizeof(h),
masked_prod, &masked_cons,
XEN_FLEX_RING_SIZE(ring->ring_order));
if (queued < le32_to_cpu(h.size_le)) {
return 0;
}
/* cannot fail, because we only handle one request per ring at a time */
pdu = pdu_alloc(&ring->priv->state);
ring->out_size = le32_to_cpu(h.size_le);
ring->out_cons = cons + le32_to_cpu(h.size_le);
pdu_submit(pdu, &h);
return 0;
}
