예제 #1
0
static gboolean cadence_uart_xmit(GIOChannel *chan, GIOCondition cond,
                                  void *opaque)
{
    UartState *s = opaque;
    int ret;

    /* instant drain the fifo when there's no back-end */
    if (!s->chr) {
        s->tx_count = 0;
    }

    if (!s->tx_count) {
        return FALSE;
    }

    ret = qemu_chr_fe_write(s->chr, s->tx_fifo, s->tx_count);
    s->tx_count -= ret;
    memmove(s->tx_fifo, s->tx_fifo + ret, s->tx_count);

    if (s->tx_count) {
        int r = qemu_chr_fe_add_watch(s->chr, G_IO_OUT, cadence_uart_xmit, s);
        assert(r);
    }

    uart_update_status(s);
    return FALSE;
}
예제 #2
0
/* Callback function that's called when the guest sends us data */
static ssize_t flush_buf(VirtIOSerialPort *port,
                         const uint8_t *buf, ssize_t len)
{
    VirtConsole *vcon = DO_UPCAST(VirtConsole, port, port);
    ssize_t ret;

    if (!vcon->chr) {
        /* If there's no backend, we can just say we consumed all data. */
        return len;
    }

    ret = qemu_chr_fe_write(vcon->chr, buf, len);
    trace_virtio_console_flush_buf(port->id, len, ret);

    if (ret < len) {
        VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(port);

        /*
         * Ideally we'd get a better error code than just -1, but
         * that's what the chardev interface gives us right now.  If
         * we had a finer-grained message, like -EPIPE, we could close
         * this connection.
         */
        if (ret < 0)
            ret = 0;
        if (!k->is_console) {
            virtio_serial_throttle_port(port, true);
            if (!vcon->watch) {
                vcon->watch = qemu_chr_fe_add_watch(vcon->chr, G_IO_OUT,
                                                    chr_write_unblocked, vcon);
            }
        }
    }
    return ret;
}
예제 #3
0
/* Callback function that's called when the guest sends us data */
static ssize_t flush_buf(VirtIOSerialPort *port,
                         const uint8_t *buf, ssize_t len)
{
    VirtConsole *vcon = VIRTIO_CONSOLE(port);
    ssize_t ret;

    if (!qemu_chr_fe_backend_connected(&vcon->chr)) {
        /* If there's no backend, we can just say we consumed all data. */
        return len;
    }

    ret = qemu_chr_fe_write(&vcon->chr, buf, len);
    trace_virtio_console_flush_buf(port->id, len, ret);

    if (ret < len) {
        VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(port);

        /*
         * Ideally we'd get a better error code than just -1, but
         * that's what the chardev interface gives us right now.  If
         * we had a finer-grained message, like -EPIPE, we could close
         * this connection.
         */
        if (ret < 0)
            ret = 0;

        /* XXX we should be queuing data to send later for the
         * console devices too rather than silently dropping
         * console data on EAGAIN. The Linux virtio-console
         * hvc driver though does sends with spinlocks held,
         * so if we enable throttling that'll stall the entire
         * guest kernel, not merely the process writing to the
         * console.
         *
         * While we could queue data for later write without
         * enabling throttling, this would result in the guest
         * being able to trigger arbitrary memory usage in QEMU
         * buffering data for later writes.
         *
         * So fixing this problem likely requires fixing the
         * Linux virtio-console hvc driver to not hold spinlocks
         * while writing, and instead merely block the process
         * that's writing. QEMU would then need some way to detect
         * if the guest had the fixed driver too, before we can
         * use throttling on host side.
         */
        if (!k->is_console) {
            virtio_serial_throttle_port(port, true);
            if (!vcon->watch) {
                vcon->watch = qemu_chr_fe_add_watch(&vcon->chr,
                                                    G_IO_OUT|G_IO_HUP,
                                                    chr_write_unblocked, vcon);
            }
        }
    }
    return ret;
}
예제 #4
0
파일: vhost-user.c 프로젝트: 8tab/qemu
static void net_vhost_user_event(void *opaque, int event)
{
    const char *name = opaque;
    NetClientState *ncs[MAX_QUEUE_NUM];
    VhostUserState *s;
    Chardev *chr;
    Error *err = NULL;
    int queues;

    queues = qemu_find_net_clients_except(name, ncs,
                                          NET_CLIENT_DRIVER_NIC,
                                          MAX_QUEUE_NUM);
    assert(queues < MAX_QUEUE_NUM);

    s = DO_UPCAST(VhostUserState, nc, ncs[0]);
    chr = qemu_chr_fe_get_driver(&s->chr);
    trace_vhost_user_event(chr->label, event);
    switch (event) {
    case CHR_EVENT_OPENED:
        if (vhost_user_start(queues, ncs, &s->chr) < 0) {
            qemu_chr_fe_disconnect(&s->chr);
            return;
        }
        s->watch = qemu_chr_fe_add_watch(&s->chr, G_IO_HUP,
                                         net_vhost_user_watch, s);
        qmp_set_link(name, true, &err);
        s->started = true;
        break;
    case CHR_EVENT_CLOSED:
        /* a close event may happen during a read/write, but vhost
         * code assumes the vhost_dev remains setup, so delay the
         * stop & clear to idle.
         * FIXME: better handle failure in vhost code, remove bh
         */
        if (s->watch) {
            AioContext *ctx = qemu_get_current_aio_context();

            g_source_remove(s->watch);
            s->watch = 0;
            qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, NULL, NULL,
                                     NULL, NULL, false);

            aio_bh_schedule_oneshot(ctx, chr_closed_bh, opaque);
        }
        break;
    }

    if (err) {
        error_report_err(err);
    }
}
예제 #5
0
파일: vhost-user.c 프로젝트: AmesianX/panda
static void net_vhost_user_event(void *opaque, int event)
{
    const char *name = opaque;
    NetClientState *ncs[MAX_QUEUE_NUM];
    VhostUserState *s;
    CharDriverState *chr;
    Error *err = NULL;
    int queues;

    queues = qemu_find_net_clients_except(name, ncs,
                                          NET_CLIENT_DRIVER_NIC,
                                          MAX_QUEUE_NUM);
    assert(queues < MAX_QUEUE_NUM);

    s = DO_UPCAST(VhostUserState, nc, ncs[0]);
    chr = qemu_chr_fe_get_driver(&s->chr);
    trace_vhost_user_event(chr->label, event);
    switch (event) {
    case CHR_EVENT_OPENED:
        s->watch = qemu_chr_fe_add_watch(&s->chr, G_IO_HUP,
                                         net_vhost_user_watch, s);
        if (vhost_user_start(queues, ncs, &s->chr) < 0) {
            qemu_chr_fe_disconnect(&s->chr);
            return;
        }
        qmp_set_link(name, true, &err);
        s->started = true;
        break;
    case CHR_EVENT_CLOSED:
        qmp_set_link(name, false, &err);
        vhost_user_stop(queues, ncs);
        g_source_remove(s->watch);
        s->watch = 0;
        break;
    }

    if (err) {
        error_report_err(err);
    }
}
예제 #6
0
static int chr_be_change(void *opaque)
{
    VirtConsole *vcon = opaque;
    VirtIOSerialPort *port = VIRTIO_SERIAL_PORT(vcon);
    VirtIOSerialPortClass *k = VIRTIO_SERIAL_PORT_GET_CLASS(port);

    if (k->is_console) {
        qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
                                 NULL, chr_be_change, vcon, NULL, true);
    } else {
        qemu_chr_fe_set_handlers(&vcon->chr, chr_can_read, chr_read,
                                 chr_event, chr_be_change, vcon, NULL, false);
    }

    if (vcon->watch) {
        g_source_remove(vcon->watch);
        vcon->watch = qemu_chr_fe_add_watch(&vcon->chr,
                                            G_IO_OUT | G_IO_HUP,
                                            chr_write_unblocked, vcon);
    }

    return 0;
}