xref: /openbmc/qemu/include/hw/virtio/virtio-bus.h (revision 0b2ff2ce)
1 /*
2  * VirtioBus
3  *
4  *  Copyright (C) 2012 : GreenSocs Ltd
5  *      http://www.greensocs.com/ , email: info@greensocs.com
6  *
7  *  Developed by :
8  *  Frederic Konrad   <fred.konrad@greensocs.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation, either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License along
21  * with this program; if not, see <http://www.gnu.org/licenses/>.
22  *
23  */
24 
25 #ifndef VIRTIO_BUS_H
26 #define VIRTIO_BUS_H
27 
28 #include "hw/qdev.h"
29 #include "sysemu/sysemu.h"
30 #include "hw/virtio/virtio.h"
31 
32 #define TYPE_VIRTIO_BUS "virtio-bus"
33 #define VIRTIO_BUS_GET_CLASS(obj) \
34         OBJECT_GET_CLASS(VirtioBusClass, obj, TYPE_VIRTIO_BUS)
35 #define VIRTIO_BUS_CLASS(klass) \
36         OBJECT_CLASS_CHECK(VirtioBusClass, klass, TYPE_VIRTIO_BUS)
37 #define VIRTIO_BUS(obj) OBJECT_CHECK(VirtioBusState, (obj), TYPE_VIRTIO_BUS)
38 
39 typedef struct VirtioBusState VirtioBusState;
40 
41 typedef struct VirtioBusClass {
42     /* This is what a VirtioBus must implement */
43     BusClass parent;
44     void (*notify)(DeviceState *d, uint16_t vector);
45     void (*save_config)(DeviceState *d, QEMUFile *f);
46     void (*save_queue)(DeviceState *d, int n, QEMUFile *f);
47     int (*load_config)(DeviceState *d, QEMUFile *f);
48     int (*load_queue)(DeviceState *d, int n, QEMUFile *f);
49     int (*load_done)(DeviceState *d, QEMUFile *f);
50     bool (*query_guest_notifiers)(DeviceState *d);
51     int (*set_guest_notifiers)(DeviceState *d, int nvqs, bool assign);
52     int (*set_host_notifier)(DeviceState *d, int n, bool assigned);
53     void (*vmstate_change)(DeviceState *d, bool running);
54     /*
55      * transport independent init function.
56      * This is called by virtio-bus just after the device is plugged.
57      */
58     void (*device_plugged)(DeviceState *d, Error **errp);
59     /*
60      * transport independent exit function.
61      * This is called by virtio-bus just before the device is unplugged.
62      */
63     void (*device_unplugged)(DeviceState *d);
64     int (*query_nvectors)(DeviceState *d);
65     /*
66      * Does the transport have variable vring alignment?
67      * (ie can it ever call virtio_queue_set_align()?)
68      * Note that changing this will break migration for this transport.
69      */
70     bool has_variable_vring_alignment;
71 } VirtioBusClass;
72 
73 struct VirtioBusState {
74     BusState parent_obj;
75 };
76 
77 void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp);
78 void virtio_bus_reset(VirtioBusState *bus);
79 void virtio_bus_device_unplugged(VirtIODevice *bus);
80 /* Get the device id of the plugged device. */
81 uint16_t virtio_bus_get_vdev_id(VirtioBusState *bus);
82 /* Get the config_len field of the plugged device. */
83 size_t virtio_bus_get_vdev_config_len(VirtioBusState *bus);
84 /* Get the features of the plugged device. */
85 uint32_t virtio_bus_get_vdev_features(VirtioBusState *bus,
86                                     uint32_t requested_features);
87 /* Get bad features of the plugged device. */
88 uint32_t virtio_bus_get_vdev_bad_features(VirtioBusState *bus);
89 /* Get config of the plugged device. */
90 void virtio_bus_get_vdev_config(VirtioBusState *bus, uint8_t *config);
91 /* Set config of the plugged device. */
92 void virtio_bus_set_vdev_config(VirtioBusState *bus, uint8_t *config);
93 
94 static inline VirtIODevice *virtio_bus_get_device(VirtioBusState *bus)
95 {
96     BusState *qbus = &bus->parent_obj;
97     BusChild *kid = QTAILQ_FIRST(&qbus->children);
98     DeviceState *qdev = kid ? kid->child : NULL;
99 
100     /* This is used on the data path, the cast is guaranteed
101      * to succeed by the qdev machinery.
102      */
103     return (VirtIODevice *)qdev;
104 }
105 
106 #endif /* VIRTIO_BUS_H */
107