aboutsummaryrefslogtreecommitdiff
path: root/hw/virtio-serial.h
blob: f297b0068934ff6747b622eabc86070cc0efeb4d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
/*
 * Virtio Serial / Console Support
 *
 * Copyright IBM, Corp. 2008
 * Copyright Red Hat, Inc. 2009
 *
 * 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 <stdbool.h>
#include "qdev.h"
#include "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

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;
    uint32_t nr_ports;
} __attribute__((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 */
};

/* Some events for the internal messages (control packets) */
#define VIRTIO_CONSOLE_PORT_READY	0
#define VIRTIO_CONSOLE_CONSOLE_PORT	1
#define VIRTIO_CONSOLE_RESIZE		2
#define VIRTIO_CONSOLE_PORT_OPEN	3
#define VIRTIO_CONSOLE_PORT_NAME	4
#define VIRTIO_CONSOLE_PORT_REMOVE	5

/* == In-qemu interface == */

typedef struct VirtIOSerial VirtIOSerial;
typedef struct VirtIOSerialBus VirtIOSerialBus;
typedef struct VirtIOSerialPort VirtIOSerialPort;
typedef struct VirtIOSerialPortInfo VirtIOSerialPortInfo;

typedef struct VirtIOSerialDevice {
    DeviceState qdev;
    VirtIOSerialPortInfo *info;
} VirtIOSerialDevice;

/*
 * 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;
    VirtIOSerialPortInfo *info;

    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;

    /* 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 {
    DeviceInfo qdev;
    /*
     * The per-port (or per-app) init function that's called when a
     * new device is found on the bus.
     */
    int (*init)(VirtIOSerialDevice *dev);
    /*
     * Per-port exit function that's called when a port gets
     * hot-unplugged or removed.
     */
    int (*exit)(VirtIOSerialDevice *dev);

    /* Callbacks for guest events */
        /* Guest opened device. */
    void (*guest_open)(VirtIOSerialPort *port);
        /* Guest closed device. */
    void (*guest_close)(VirtIOSerialPort *port);

        /* 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 should return the number of
     * bytes it successfully consumed.
     */
    size_t (*have_data)(VirtIOSerialPort *port, const uint8_t *buf, size_t len);
};

/* Interface to the virtio-serial bus */

/*
 * Individual ports/apps should call this function to register the port
 * with the virtio-serial bus
 */
void virtio_serial_port_qdev_register(VirtIOSerialPortInfo *info);

/*
 * 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);

#endif