summaryrefslogtreecommitdiffstats
path: root/include/hw/virtio/virtio-bus.h
blob: ef8abe49c5a160a078a50181cf8f82ff9af79858 (plain) (blame)
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
/*
 * VirtioBus
 *
 *  Copyright (C) 2012 : GreenSocs Ltd
 *      http://www.greensocs.com/ , email: info@greensocs.com
 *
 *  Developed by :
 *  Frederic Konrad   <fred.konrad@greensocs.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef VIRTIO_BUS_H
#define VIRTIO_BUS_H

#include "hw/qdev-core.h"
#include "hw/virtio/virtio.h"
#include "qom/object.h"

#define TYPE_VIRTIO_BUS "virtio-bus"
typedef struct VirtioBusClass VirtioBusClass;
typedef struct VirtioBusState VirtioBusState;
DECLARE_OBJ_CHECKERS(VirtioBusState, VirtioBusClass,
                     VIRTIO_BUS, TYPE_VIRTIO_BUS)


struct VirtioBusClass {
    /* This is what a VirtioBus must implement */
    BusClass parent;
    void (*notify)(DeviceState *d, uint16_t vector);
    void (*save_config)(DeviceState *d, QEMUFile *f);
    void (*save_queue)(DeviceState *d, int n, QEMUFile *f);
    void (*save_extra_state)(DeviceState *d, QEMUFile *f);
    int (*load_config)(DeviceState *d, QEMUFile *f);
    int (*load_queue)(DeviceState *d, int n, QEMUFile *f);
    int (*load_done)(DeviceState *d, QEMUFile *f);
    int (*load_extra_state)(DeviceState *d, QEMUFile *f);
    bool (*has_extra_state)(DeviceState *d);
    bool (*query_guest_notifiers)(DeviceState *d);
    int (*set_guest_notifiers)(DeviceState *d, int nvqs, bool assign);
    int (*set_host_notifier_mr)(DeviceState *d, int n,
                                MemoryRegion *mr, bool assign);
    void (*vmstate_change)(DeviceState *d, bool running);
    /*
     * Expose the features the transport layer supports before
     * the negotiation takes place.
     */
    void (*pre_plugged)(DeviceState *d, Error **errp);
    /*
     * transport independent init function.
     * This is called by virtio-bus just after the device is plugged.
     */
    void (*device_plugged)(DeviceState *d, Error **errp);
    /*
     * transport independent exit function.
     * This is called by virtio-bus just before the device is unplugged.
     */
    void (*device_unplugged)(DeviceState *d);
    int (*query_nvectors)(DeviceState *d);
    /*
     * ioeventfd handling: if the transport implements ioeventfd_assign,
     * it must implement ioeventfd_enabled as well.
     */
    /* Returns true if the ioeventfd is enabled for the device. */
    bool (*ioeventfd_enabled)(DeviceState *d);
    /*
     * Assigns/deassigns the ioeventfd backing for the transport on
     * the device for queue number n. Returns an error value on
     * failure.
     */
    int (*ioeventfd_assign)(DeviceState *d, EventNotifier *notifier,
                            int n, bool assign);
    /*
     * Whether queue number n is enabled.
     */
    bool (*queue_enabled)(DeviceState *d, int n);
    /*
     * Does the transport have variable vring alignment?
     * (ie can it ever call virtio_queue_set_align()?)
     * Note that changing this will break migration for this transport.
     */
    bool has_variable_vring_alignment;
    AddressSpace *(*get_dma_as)(DeviceState *d);
};

struct VirtioBusState {
    BusState parent_obj;

    /*
     * Set if ioeventfd has been started.
     */
    bool ioeventfd_started;

    /*
     * Set if ioeventfd has been grabbed by vhost.  When ioeventfd
     * is grabbed by vhost, we track its started/stopped state (which
     * depends in turn on the virtio status register), but do not
     * register a handler for the ioeventfd.  When ioeventfd is
     * released, if ioeventfd_started is true we finally register
     * the handler so that QEMU's device model can use ioeventfd.
     */
    int ioeventfd_grabbed;
};

void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp);
void virtio_bus_reset(VirtioBusState *bus);
void virtio_bus_device_unplugged(VirtIODevice *bus);
/* Get the device id of the plugged device. */
uint16_t virtio_bus_get_vdev_id(VirtioBusState *bus);
/* Get the config_len field of the plugged device. */
size_t virtio_bus_get_vdev_config_len(VirtioBusState *bus);
/* Get bad features of the plugged device. */
uint32_t virtio_bus_get_vdev_bad_features(VirtioBusState *bus);
/* Get config of the plugged device. */
void virtio_bus_get_vdev_config(VirtioBusState *bus, uint8_t *config);
/* Set config of the plugged device. */
void virtio_bus_set_vdev_config(VirtioBusState *bus, uint8_t *config);

static inline VirtIODevice *virtio_bus_get_device(VirtioBusState *bus)
{
    BusState *qbus = &bus->parent_obj;
    BusChild *kid = QTAILQ_FIRST(&qbus->children);
    DeviceState *qdev = kid ? kid->child : NULL;

    /* This is used on the data path, the cast is guaranteed
     * to succeed by the qdev machinery.
     */
    return (VirtIODevice *)qdev;
}

/* Return whether the proxy allows ioeventfd.  */
bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus);
/* Start the ioeventfd. */
int virtio_bus_start_ioeventfd(VirtioBusState *bus);
/* Stop the ioeventfd. */
void virtio_bus_stop_ioeventfd(VirtioBusState *bus);
/* Tell the bus that vhost is grabbing the ioeventfd. */
int virtio_bus_grab_ioeventfd(VirtioBusState *bus);
/* bus that vhost is not using the ioeventfd anymore. */
void virtio_bus_release_ioeventfd(VirtioBusState *bus);
/* Switch from/to the generic ioeventfd handler */
int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign);
/* Tell the bus that the ioeventfd handler is no longer required. */
void virtio_bus_cleanup_host_notifier(VirtioBusState *bus, int n);

#endif /* VIRTIO_BUS_H */