xref: /openbmc/qemu/include/hw/virtio/virtio-bus.h (revision 416296a9)
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     void (*save_extra_state)(DeviceState *d, QEMUFile *f);
48     int (*load_config)(DeviceState *d, QEMUFile *f);
49     int (*load_queue)(DeviceState *d, int n, QEMUFile *f);
50     int (*load_done)(DeviceState *d, QEMUFile *f);
51     int (*load_extra_state)(DeviceState *d, QEMUFile *f);
52     bool (*has_extra_state)(DeviceState *d);
53     bool (*query_guest_notifiers)(DeviceState *d);
54     int (*set_guest_notifiers)(DeviceState *d, int nvqs, bool assign);
55     void (*vmstate_change)(DeviceState *d, bool running);
56     /*
57      * transport independent init function.
58      * This is called by virtio-bus just after the device is plugged.
59      */
60     void (*device_plugged)(DeviceState *d, Error **errp);
61     /*
62      * Re-evaluate setup after feature bits have been validated
63      * by the device backend.
64      */
65     void (*post_plugged)(DeviceState *d, Error **errp);
66     /*
67      * transport independent exit function.
68      * This is called by virtio-bus just before the device is unplugged.
69      */
70     void (*device_unplugged)(DeviceState *d);
71     int (*query_nvectors)(DeviceState *d);
72     /*
73      * ioeventfd handling: if the transport implements ioeventfd_started,
74      * it must implement the other ioeventfd callbacks as well
75      */
76     /* Returns true if the ioeventfd has been started for the device. */
77     bool (*ioeventfd_started)(DeviceState *d);
78     /*
79      * Sets the 'ioeventfd started' state after the ioeventfd has been
80      * started/stopped for the device. err signifies whether an error
81      * had occurred.
82      */
83     void (*ioeventfd_set_started)(DeviceState *d, bool started, bool err);
84     /* Returns true if the ioeventfd has been disabled for the device. */
85     bool (*ioeventfd_disabled)(DeviceState *d);
86     /* Sets the 'ioeventfd disabled' state for the device. */
87     void (*ioeventfd_set_disabled)(DeviceState *d, bool disabled);
88     /*
89      * Assigns/deassigns the ioeventfd backing for the transport on
90      * the device for queue number n. Returns an error value on
91      * failure.
92      */
93     int (*ioeventfd_assign)(DeviceState *d, EventNotifier *notifier,
94                             int n, bool assign);
95     /*
96      * Does the transport have variable vring alignment?
97      * (ie can it ever call virtio_queue_set_align()?)
98      * Note that changing this will break migration for this transport.
99      */
100     bool has_variable_vring_alignment;
101 } VirtioBusClass;
102 
103 struct VirtioBusState {
104     BusState parent_obj;
105 };
106 
107 void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp);
108 void virtio_bus_reset(VirtioBusState *bus);
109 void virtio_bus_device_unplugged(VirtIODevice *bus);
110 /* Get the device id of the plugged device. */
111 uint16_t virtio_bus_get_vdev_id(VirtioBusState *bus);
112 /* Get the config_len field of the plugged device. */
113 size_t virtio_bus_get_vdev_config_len(VirtioBusState *bus);
114 /* Get bad features of the plugged device. */
115 uint32_t virtio_bus_get_vdev_bad_features(VirtioBusState *bus);
116 /* Get config of the plugged device. */
117 void virtio_bus_get_vdev_config(VirtioBusState *bus, uint8_t *config);
118 /* Set config of the plugged device. */
119 void virtio_bus_set_vdev_config(VirtioBusState *bus, uint8_t *config);
120 
121 static inline VirtIODevice *virtio_bus_get_device(VirtioBusState *bus)
122 {
123     BusState *qbus = &bus->parent_obj;
124     BusChild *kid = QTAILQ_FIRST(&qbus->children);
125     DeviceState *qdev = kid ? kid->child : NULL;
126 
127     /* This is used on the data path, the cast is guaranteed
128      * to succeed by the qdev machinery.
129      */
130     return (VirtIODevice *)qdev;
131 }
132 
133 /* Start the ioeventfd. */
134 void virtio_bus_start_ioeventfd(VirtioBusState *bus);
135 /* Stop the ioeventfd. */
136 void virtio_bus_stop_ioeventfd(VirtioBusState *bus);
137 /* Switch from/to the generic ioeventfd handler */
138 int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign);
139 
140 #endif /* VIRTIO_BUS_H */
141