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Diffstat (limited to 'include/hw/virtio/virtio-serial.h')
-rw-r--r-- | include/hw/virtio/virtio-serial.h | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/include/hw/virtio/virtio-serial.h b/include/hw/virtio/virtio-serial.h new file mode 100644 index 0000000..098deea --- /dev/null +++ b/include/hw/virtio/virtio-serial.h @@ -0,0 +1,247 @@ +/* + * 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 "hw/qdev.h" +#include "hw/virtio/virtio.h" + +/* == Interface shared between the guest kernel and qemu == */ + +/* The Virtio ID for virtio console / serial ports */ +#define VIRTIO_ID_CONSOLE 3 + +/* Features supported */ +#define VIRTIO_CONSOLE_F_MULTIPORT 1 + +#define VIRTIO_CONSOLE_BAD_ID (~(uint32_t)0) + +struct virtio_console_config { + /* + * These two fields are used by VIRTIO_CONSOLE_F_SIZE which + * isn't implemented here yet + */ + uint16_t cols; + uint16_t rows; + + uint32_t max_nr_ports; +} QEMU_PACKED; + +struct virtio_console_control { + uint32_t id; /* Port number */ + uint16_t event; /* The kind of control event (see below) */ + uint16_t value; /* Extra information for the key */ +}; + +struct virtio_serial_conf { + /* Max. number of ports we can have for a virtio-serial device */ + uint32_t max_virtserial_ports; +}; + +/* Some events for the internal messages (control packets) */ +#define VIRTIO_CONSOLE_DEVICE_READY 0 +#define VIRTIO_CONSOLE_PORT_ADD 1 +#define VIRTIO_CONSOLE_PORT_REMOVE 2 +#define VIRTIO_CONSOLE_PORT_READY 3 +#define VIRTIO_CONSOLE_CONSOLE_PORT 4 +#define VIRTIO_CONSOLE_RESIZE 5 +#define VIRTIO_CONSOLE_PORT_OPEN 6 +#define VIRTIO_CONSOLE_PORT_NAME 7 + +/* == In-qemu interface == */ + +#define TYPE_VIRTIO_SERIAL_PORT "virtio-serial-port" +#define VIRTIO_SERIAL_PORT(obj) \ + OBJECT_CHECK(VirtIOSerialPort, (obj), TYPE_VIRTIO_SERIAL_PORT) +#define VIRTIO_SERIAL_PORT_CLASS(klass) \ + OBJECT_CLASS_CHECK(VirtIOSerialPortClass, (klass), TYPE_VIRTIO_SERIAL_PORT) +#define VIRTIO_SERIAL_PORT_GET_CLASS(obj) \ + OBJECT_GET_CLASS(VirtIOSerialPortClass, (obj), TYPE_VIRTIO_SERIAL_PORT) + +typedef struct VirtIOSerial VirtIOSerial; +typedef struct VirtIOSerialBus VirtIOSerialBus; +typedef struct VirtIOSerialPort VirtIOSerialPort; + +typedef 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) init function that's called when a + * new device is found on the bus. + */ + int (*init)(VirtIOSerialPort *port); + /* + * Per-port exit function that's called when a port gets + * hot-unplugged or removed. + */ + int (*exit)(VirtIOSerialPort *port); + + /* Callbacks for guest events */ + /* Guest opened/closed device. */ + void (*set_guest_connected)(VirtIOSerialPort *port, int guest_connected); + + /* Guest is now ready to accept data (virtqueues set up). */ + void (*guest_ready)(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, + size_t len); +} VirtIOSerialPortClass; + +/* + * 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 vdev; + + VirtQueue *c_ivq, *c_ovq; + /* Arrays of ivqs and ovqs: one per port */ + VirtQueue **ivqs, **ovqs; + + VirtIOSerialBus bus; + + DeviceState *qdev; + + QTAILQ_HEAD(, VirtIOSerialPort) ports; + + /* bitmap for identifying active ports */ + uint32_t *ports_map; + + struct virtio_console_config config; + + struct VirtIOSerialPostLoad *post_load; +}; + +/* 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); + +#endif |