| From 4945aee74f494cc8a17ce1634b5200eb9ee227d2 Mon Sep 17 00:00:00 2001 |
| From: Amit Shah <amit.shah@redhat.com> |
| Date: Wed, 20 Jan 2010 00:36:53 +0530 |
| Subject: [PATCH 3/9] virtio-serial-bus: Maintain guest and host port open/close state |
| |
| 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> |
| Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> |
| |
| hw/virtio-serial-bus.c | 94 ++++++++++++++++++++++++++++++++++++++++++++++++ |
| hw/virtio-serial.h | 6 +++ |
| 2 files changed, 100 insertions(+), 0 deletions(-) |
| |
| diff --git a/hw/virtio-serial-bus.c b/hw/virtio-serial-bus.c |
| index 5132c9c..9af21df 100644 |
| |
| |
| @@ -66,6 +66,11 @@ static VirtIOSerialPort *find_port_by_vq(VirtIOSerial *vser, VirtQueue *vq) |
| return NULL; |
| } |
| |
| +static bool use_multiport(VirtIOSerial *vser) |
| +{ |
| + return vser->vdev.features & (1 << VIRTIO_CONSOLE_F_MULTIPORT); |
| +} |
| + |
| static size_t write_to_port(VirtIOSerialPort *port, |
| const uint8_t *buf, size_t size) |
| { |
| @@ -139,11 +144,22 @@ 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; |
| } |
| |
| @@ -151,6 +167,9 @@ 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); |
| } |
| |
| @@ -167,6 +186,9 @@ size_t virtio_serial_guest_ready(VirtIOSerialPort *port) |
| virtio_queue_empty(vq)) { |
| return 0; |
| } |
| + if (use_multiport(port->vser) && !port->guest_connected) { |
| + return 0; |
| + } |
| |
| if (virtqueue_avail_bytes(vq, 4096, 0)) { |
| return 4096; |
| @@ -203,6 +225,11 @@ 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 |
| @@ -213,6 +240,19 @@ 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; |
| } |
| } |
| |
| @@ -300,6 +340,8 @@ 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); |
| @@ -308,15 +350,41 @@ 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); |
| |
| @@ -329,6 +397,20 @@ 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; |
| } |
| |
| @@ -357,6 +439,10 @@ 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) |
| @@ -390,6 +476,14 @@ 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]; |
| diff --git a/hw/virtio-serial.h b/hw/virtio-serial.h |
| index fe8e357..d9c7acb 100644 |
| |
| |
| @@ -49,6 +49,7 @@ struct virtio_console_control { |
| #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 == */ |
| |
| @@ -92,6 +93,11 @@ 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 { |
| -- |
| 1.6.2.5 |
| |