/*
* Virtio Serial / Console Support
*
* Copyright IBM, Corp. 2008
* Copyright Red Hat, Inc. 2009, 2010
*
* Authors:
* Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
* Amit Shah <amit.shah@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#ifndef QEMU_VIRTIO_SERIAL_H
#define QEMU_VIRTIO_SERIAL_H
#include "standard-headers/linux/virtio_console.h"
#include "hw/virtio/virtio.h"
#include "qom/object.h"
struct virtio_serial_conf {
/* Max. number of ports we can have for a virtio-serial device */
uint32_t max_virtserial_ports;
};
#define TYPE_VIRTIO_SERIAL_PORT "virtio-serial-port"
OBJECT_DECLARE_TYPE(VirtIOSerialPort, VirtIOSerialPortClass,
VIRTIO_SERIAL_PORT)
typedef struct VirtIOSerial VirtIOSerial;
#define TYPE_VIRTIO_SERIAL_BUS "virtio-serial-bus"
OBJECT_DECLARE_SIMPLE_TYPE(VirtIOSerialBus, VIRTIO_SERIAL_BUS)
struct VirtIOSerialPortClass {
DeviceClass parent_class;
/* Is this a device that binds with hvc in the guest? */
bool is_console;
/*
* The per-port (or per-app) realize function that's called when a
* new device is found on the bus.
*/
DeviceRealize realize;
/*
* Per-port unrealize function that's called when a port gets
* hot-unplugged or removed.
*/
DeviceUnrealize unrealize;
/* Callbacks for guest events */
/* Guest opened/closed device. */
void (*set_guest_connected)(VirtIOSerialPort *port, int guest_connected);
/* Enable/disable backend for virtio serial port */
void (*enable_backend)(VirtIOSerialPort *port, bool enable);
/* Guest is now ready to accept data (virtqueues set up). */
void (*guest_ready)(VirtIOSerialPort *port);
/*
* Guest has enqueued a buffer for the host to write into.
* Called each time a buffer is enqueued by the guest;
* irrespective of whether there already were free buffers the
* host could have consumed.
*
* This is dependent on both the guest and host end being
* connected.
*/
void (*guest_writable)(VirtIOSerialPort *port);
/*
* Guest wrote some data to the port. This data is handed over to
* the app via this callback. The app can return a size less than
* 'len'. In this case, throttling will be enabled for this port.
*/
ssize_t (*have_data)(VirtIOSerialPort *port, const uint8_t *buf,
ssize_t len);
};
/*
* This is the state that's shared between all the ports. Some of the
* state is configurable via command-line options. Some of it can be
* set by individual devices in their initfn routines. Some of the
* state is set by the generic qdev device init routine.
*/
struct VirtIOSerialPort {
DeviceState dev;
QTAILQ_ENTRY(VirtIOSerialPort) next;
/*
* This field gives us the virtio device as well as the qdev bus
* that we are associated with
*/
VirtIOSerial *vser;
VirtQueue *ivq, *ovq;
/*
* This name is sent to the guest and exported via sysfs.
* The guest could create symlinks based on this information.
* The name is in the reverse fqdn format, like org.qemu.console.0
*/
char *name;
/*
* This id helps identify ports between the guest and the host.
* The guest sends a "header" with this id with each data packet
* that it sends and the host can then find out which associated
* device to send out this data to
*/
uint32_t id;
/*
* This is the elem that we pop from the virtqueue. A slow
* backend that consumes guest data (e.g. the file backend for
* qemu chardevs) can cause the guest to block till all the output
* is flushed. This isn't desired, so we keep a note of the last
* element popped and continue consuming it once the backend
* becomes writable again.
*/
VirtQueueElement *elem;
/*
* The index and the offset into the iov buffer that was popped in
* elem above.
*/
uint32_t iov_idx;
uint64_t iov_offset;
/*
* When unthrottling we use a bottom-half to call flush_queued_data.
*/
QEMUBH *bh;
/* Is the corresponding guest device open? */
bool guest_connected;
/* Is this device open for IO on the host? */
bool host_connected;
/* Do apps not want to receive data? */
bool throttled;
};
/* The virtio-serial bus on top of which the ports will ride as devices */
struct VirtIOSerialBus {
BusState qbus;
/* This is the parent device that provides the bus for ports. */
VirtIOSerial *vser;
/* The maximum number of ports that can ride on top of this bus */
uint32_t max_nr_ports;
};
typedef struct VirtIOSerialPostLoad {
QEMUTimer *timer;
uint32_t nr_active_ports;
struct {
VirtIOSerialPort *port;
uint8_t host_connected;
} *connected;
} VirtIOSerialPostLoad;
struct VirtIOSerial {
VirtIODevice parent_obj;
VirtQueue *c_ivq, *c_ovq;
/* Arrays of ivqs and ovqs: one per port */
VirtQueue **ivqs, **ovqs;
VirtIOSerialBus bus;
QTAILQ_HEAD(, VirtIOSerialPort) ports;
QLIST_ENTRY(VirtIOSerial) next;
/* bitmap for identifying active ports */
uint32_t *ports_map;
struct VirtIOSerialPostLoad *post_load;
virtio_serial_conf serial;
uint64_t host_features;
};
/* Interface to the virtio-serial bus */
/*
* Open a connection to the port
* Returns 0 on success (always).
*/
int virtio_serial_open(VirtIOSerialPort *port);
/*
* Close the connection to the port
* Returns 0 on success (always).
*/
int virtio_serial_close(VirtIOSerialPort *port);
/*
* Send data to Guest
*/
ssize_t virtio_serial_write(VirtIOSerialPort *port, const uint8_t *buf,
size_t size);
/*
* Query whether a guest is ready to receive data.
*/
size_t virtio_serial_guest_ready(VirtIOSerialPort *port);
/*
* Flow control: Ports can signal to the virtio-serial core to stop
* sending data or re-start sending data, depending on the 'throttle'
* value here.
*/
void virtio_serial_throttle_port(VirtIOSerialPort *port, bool throttle);
#define TYPE_VIRTIO_SERIAL "virtio-serial-device"
OBJECT_DECLARE_SIMPLE_TYPE(VirtIOSerial, VIRTIO_SERIAL)
#endif
