From: Sascha Silbe <si...@linux.vnet.ibm.com>
Add the infrastructure required for the virtio 1.0 "emergency write"
(VIRTIO_CONSOLE_F_EMERG_WRITE) feature. Because we don't touch the
size of the configuration area, guests will not be able to actually
make use of this without further patches.
Reviewed-by: Cornelia Huck <cornelia.h...@de.ibm.com>
Signed-off-by: Sascha Silbe <si...@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <m...@redhat.com>
Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
---
hw/char/virtio-serial-bus.c | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c
index db57a38..57419b2 100644
--- a/hw/char/virtio-serial-bus.c
+++ b/hw/char/virtio-serial-bus.c
@@ -75,6 +75,19 @@ static VirtIOSerialPort *find_port_by_name(char *name)
return NULL;
}
+static VirtIOSerialPort *find_first_connected_console(VirtIOSerial *vser)
+{
+ VirtIOSerialPort *port;
+
+ QTAILQ_FOREACH(port, &vser->ports, next) {
+ VirtIOSerialPortClass const *vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port);
+ if (vsc->is_console && port->host_connected) {
+ return port;
+ }
+ }
+ return NULL;
+}
+
static bool use_multiport(VirtIOSerial *vser)
{
VirtIODevice *vdev = VIRTIO_DEVICE(vser);
@@ -547,6 +560,29 @@ static void get_config(VirtIODevice *vdev, uint8_t
*config_data)
vser->serial.max_virtserial_ports);
}
+/* Guest sent new config info */
+static void set_config(VirtIODevice *vdev, const uint8_t *config_data)
+{
+ VirtIOSerial *vser = VIRTIO_SERIAL(vdev);
+ struct virtio_console_config *config =
+ (struct virtio_console_config *)config_data;
+ uint8_t emerg_wr_lo = le32_to_cpu(config->emerg_wr);
+ VirtIOSerialPort *port = find_first_connected_console(vser);
+ VirtIOSerialPortClass *vsc;
+
+ if (!config->emerg_wr) {
+ return;
+ }
+ /* Make sure we don't misdetect an emergency write when the guest
+ * does a short config write after an emergency write. */
+ config->emerg_wr = 0;
+ if (!port) {
+ return;
+ }
+ vsc = VIRTIO_SERIAL_PORT_GET_CLASS(port);
+ (void)vsc->have_data(port, &emerg_wr_lo, 1);
+}
+
static void guest_reset(VirtIOSerial *vser)
{
VirtIOSerialPort *port;
@@ -1098,6 +1134,7 @@ static void virtio_serial_class_init(ObjectClass *klass,
void *data)
vdc->unrealize = virtio_serial_device_unrealize;
vdc->get_features = get_features;
vdc->get_config = get_config;
+ vdc->set_config = set_config;
vdc->set_status = set_status;
vdc->reset = vser_reset;
vdc->save = virtio_serial_save_device;
--
MST
