@@ -160,11 +160,22 @@ static size_t send_control_event(VirtIOSerialPort *port, uint16_t event,
/* Functions for use inside qemu to open and read from/write to ports */
int virtio_serial_open(VirtIOSerialPort *port)
{
+ /* Don't allow opening an already-open port */
+ if (port->host_connected) {
+ return 0;
+ }
+ /* Send port open notification to the guest */
+ port->host_connected = true;
+ send_control_event(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
+
return 0;
}
int virtio_serial_close(VirtIOSerialPort *port)
{
+ port->host_connected = false;
+ send_control_event(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
+
return 0;
}
@@ -172,6 +183,9 @@ int virtio_serial_close(VirtIOSerialPort *port)
ssize_t virtio_serial_write(VirtIOSerialPort *port, const uint8_t *buf,
size_t size)
{
+ if (!port || !port->host_connected || !port->guest_connected) {
+ return 0;
+ }
return write_to_port(port, buf, size);
}
@@ -192,6 +206,9 @@ size_t virtio_serial_guest_ready(VirtIOSerialPort *port)
virtio_queue_empty(vq)) {
return 0;
}
+ if (use_multiport(port->vser) && !port->guest_connected) {
+ return 0;
+ }
size = 4096;
if (virtqueue_avail_bytes(vq, size, 0)) {
@@ -230,6 +247,11 @@ static void handle_control_message(VirtIOSerial *vser, void *buf)
if (port->is_console) {
send_control_event(port, VIRTIO_CONSOLE_CONSOLE_PORT, 1);
}
+
+ if (port->host_connected) {
+ send_control_event(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
+ }
+
/*
* When the guest has asked us for this information it means
* the guest is all setup and has its virtqueues
@@ -240,6 +262,19 @@ static void handle_control_message(VirtIOSerial *vser, void *buf)
port->info->guest_ready(port);
}
break;
+
+ case VIRTIO_CONSOLE_PORT_OPEN:
+ port->guest_connected = cpkt.value;
+ if (cpkt.value && port->info->guest_open) {
+ /* Send the guest opened notification if an app is interested */
+ port->info->guest_open(port);
+ }
+
+ if (!cpkt.value && port->info->guest_close) {
+ /* Send the guest closed notification if an app is interested */
+ port->info->guest_close(port);
+ }
+ break;
}
}
@@ -334,6 +369,8 @@ static void set_config(VirtIODevice *vdev, const uint8_t *config_data)
static void virtio_serial_save(QEMUFile *f, void *opaque)
{
VirtIOSerial *s = opaque;
+ VirtIOSerialPort *port;
+ uint32_t nr_active_ports;
/* The virtio device */
virtio_save(&s->vdev, f);
@@ -342,15 +379,42 @@ static void virtio_serial_save(QEMUFile *f, void *opaque)
qemu_put_be16s(f, &s->config.cols);
qemu_put_be16s(f, &s->config.rows);
qemu_put_be32s(f, &s->config.nr_ports);
+
+ /* Items in struct VirtIOSerial */
+
+ /* Do this because we might have hot-unplugged some ports */
+ nr_active_ports = 0;
+ QTAILQ_FOREACH(port, &s->ports, next)
+ nr_active_ports++;
+
+ qemu_put_be32s(f, &nr_active_ports);
+
+ /*
+ * Items in struct VirtIOSerialPort.
+ */
+ QTAILQ_FOREACH(port, &s->ports, next) {
+ /*
+ * We put the port number because we may not have an active
+ * port at id 0 that's reserved for a console port, or in case
+ * of ports that might have gotten unplugged
+ */
+ qemu_put_be32s(f, &port->id);
+ qemu_put_byte(f, port->guest_connected);
+
+ }
}
static int virtio_serial_load(QEMUFile *f, void *opaque, int version_id)
{
VirtIOSerial *s = opaque;
+ VirtIOSerialPort *port;
+ uint32_t nr_active_ports;
+ unsigned int i;
if (version_id > 2) {
return -EINVAL;
}
+
/* The virtio device */
virtio_load(&s->vdev, f);
@@ -363,6 +427,21 @@ static int virtio_serial_load(QEMUFile *f, void *opaque, int version_id)
qemu_get_be16s(f, &s->config.rows);
s->config.nr_ports = qemu_get_be32(f);
+ /* Items in struct VirtIOSerial */
+
+ qemu_get_be32s(f, &nr_active_ports);
+
+ /* Items in struct VirtIOSerialPort */
+ for (i = 0; i < nr_active_ports; i++) {
+ uint32_t id;
+
+ id = qemu_get_be32(f);
+ port = find_port_by_id(s, id);
+
+ port->guest_connected = qemu_get_byte(f);
+
+ }
+
return 0;
}
@@ -392,6 +471,10 @@ static void virtser_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent)
monitor_printf(mon, "%*s dev-prop-int: id: %u\n",
indent, "", port->id);
+ monitor_printf(mon, "%*s dev-prop-int: guest_connected: %d\n",
+ indent, "", port->guest_connected);
+ monitor_printf(mon, "%*s dev-prop-int: host_connected: %d\n",
+ indent, "", port->host_connected);
}
static int virtser_port_qdev_init(DeviceState *qdev, DeviceInfo *base)
@@ -425,6 +508,14 @@ static int virtser_port_qdev_init(DeviceState *qdev, DeviceInfo *base)
port->id = plugging_port0 ? 0 : port->vser->config.nr_ports++;
+ if (!use_multiport(port->vser)) {
+ /*
+ * Allow writes to guest in this case; we have no way of
+ * knowing if a guest port is connected.
+ */
+ port->guest_connected = true;
+ }
+
QTAILQ_INSERT_TAIL(&port->vser->ports, port, next);
port->ivq = port->vser->ivqs[port->id];
port->ovq = port->vser->ovqs[port->id];
@@ -68,6 +68,12 @@ static int virtconsole_initfn(VirtIOSerialDevice *dev)
port->is_console = true;
+ /*
+ * For console ports, just assume the guest is ready to accept our
+ * data.
+ */
+ port->guest_connected = true;
+
if (vcon->chr) {
qemu_chr_add_handlers(vcon->chr, chr_can_read, chr_read, chr_event,
vcon);
@@ -53,6 +53,7 @@ struct virtio_console_header {
#define VIRTIO_CONSOLE_PORT_READY 0
#define VIRTIO_CONSOLE_CONSOLE_PORT 1
#define VIRTIO_CONSOLE_RESIZE 2
+#define VIRTIO_CONSOLE_PORT_OPEN 3
/* == In-qemu interface == */
@@ -96,6 +97,11 @@ struct VirtIOSerialPort {
/* Identify if this is a port that binds with hvc in the guest */
uint8_t is_console;
+
+ /* Is the corresponding guest device open? */
+ bool guest_connected;
+ /* Is this device open for IO on the host? */
+ bool host_connected;
};
struct VirtIOSerialPortInfo {
Via control channel messages, the guest can tell us whether a port got opened or closed. Similarly, we can also indicate to the guest of host port open/close events. Signed-off-by: Amit Shah <amit.shah@redhat.com> --- hw/virtio-serial-bus.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++ hw/virtio-serial.c | 6 +++ hw/virtio-serial.h | 6 +++ 3 files changed, 103 insertions(+), 0 deletions(-)