static void
pci_vtcon_sock_rx(int fd __unused, enum ev_type t __unused, void *arg)
{
struct pci_vtcon_port *port;
struct pci_vtcon_sock *sock = (struct pci_vtcon_sock *)arg;
struct vqueue_info *vq;
struct iovec iov;
static char dummybuf[2048];
int len, n;
uint16_t idx;
port = sock->vss_port;
vq = pci_vtcon_port_to_vq(port, true);
if (!sock->vss_open || !port->vsp_rx_ready) {
len = read(sock->vss_conn_fd, dummybuf, sizeof(dummybuf));
if (len == 0)
goto close;
return;
}
if (!vq_has_descs(vq)) {
len = read(sock->vss_conn_fd, dummybuf, sizeof(dummybuf));
vq_endchains(vq, 1);
if (len == 0)
goto close;
return;
}
do {
n = vq_getchain(vq, &idx, &iov, 1, NULL);
len = readv(sock->vss_conn_fd, &iov, n);
if (len == 0 || (len < 0 && errno == EWOULDBLOCK)) {
vq_retchain(vq);
vq_endchains(vq, 0);
if (len == 0)
goto close;
return;
}
vq_relchain(vq, idx, len);
} while (vq_has_descs(vq));
vq_endchains(vq, 1);
close:
mevent_delete_close(sock->vss_conn_evp);
sock->vss_conn_fd = -1;
sock->vss_open = false;
}
static void
pci_vtnet_tap_rx(struct pci_vtnet_softc *sc)
{
struct iovec iov[VTNET_MAXSEGS], *riov;
struct vqueue_info *vq;
void *vrx;
int len, n;
uint16_t idx;
/*
* Should never be called without a valid tap fd
*/
assert(sc->vsc_tapfd != -1);
/*
* But, will be called when the rx ring hasn't yet
* been set up or the guest is resetting the device.
*/
if (!sc->vsc_rx_ready || sc->resetting) {
/*
* Drop the packet and try later.
*/
(void) read(sc->vsc_tapfd, dummybuf, sizeof(dummybuf));
return;
}
/*
* Check for available rx buffers
*/
vq = &sc->vsc_queues[VTNET_RXQ];
if (!vq_has_descs(vq)) {
/*
* Drop the packet and try later. Interrupt on
* empty, if that's negotiated.
*/
(void) read(sc->vsc_tapfd, dummybuf, sizeof(dummybuf));
vq_endchains(vq, 1);
return;
}
do {
/*
* Get descriptor chain.
*/
n = vq_getchain(vq, &idx, iov, VTNET_MAXSEGS, NULL);
assert(n >= 1 && n <= VTNET_MAXSEGS);
/*
* Get a pointer to the rx header, and use the
* data immediately following it for the packet buffer.
*/
vrx = iov[0].iov_base;
riov = rx_iov_trim(iov, &n, sc->rx_vhdrlen);
len = (int) readv(sc->vsc_tapfd, riov, n);
if (len < 0 && errno == EWOULDBLOCK) {
/*
* No more packets, but still some avail ring
* entries. Interrupt if needed/appropriate.
*/
vq_retchain(vq);
vq_endchains(vq, 0);
return;
}
/*
* The only valid field in the rx packet header is the
* number of buffers if merged rx bufs were negotiated.
*/
memset(vrx, 0, sc->rx_vhdrlen);
if (sc->rx_merge) {
struct virtio_net_rxhdr *vrxh;
vrxh = vrx;
vrxh->vrh_bufs = 1;
}
/*
* Release this chain and handle more chains.
*/
vq_relchain(vq, idx, ((uint32_t) (len + sc->rx_vhdrlen)));
} while (vq_has_descs(vq));
/* Interrupt if needed, including for NOTIFY_ON_EMPTY. */
vq_endchains(vq, 1);
}
