xref: /qemu/hw/core/qdev-hotplug.c (revision ccaca8929d53b23e2f7acc45cc88d05fc0479a1b)
1 /*
2  * QDev Hotplug handlers
3  *
4  * Copyright (c) Red Hat
5  *
6  * SPDX-License-Identifier: GPL-2.0-or-later
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or later.
9  * See the COPYING file in the top-level directory.
10  */
11 
12 #include "qemu/osdep.h"
13 #include "hw/qdev-core.h"
14 #include "hw/boards.h"
15 #include "qapi/error.h"
16 
17 HotplugHandler *qdev_get_machine_hotplug_handler(DeviceState *dev)
18 {
19     MachineState *machine;
20     MachineClass *mc;
21     Object *m_obj = qdev_get_machine();
22 
23     if (object_dynamic_cast(m_obj, TYPE_MACHINE)) {
24         machine = MACHINE(m_obj);
25         mc = MACHINE_GET_CLASS(machine);
26         if (mc->get_hotplug_handler) {
27             return mc->get_hotplug_handler(machine, dev);
28         }
29     }
30 
31     return NULL;
32 }
33 
34 static bool qdev_hotplug_unplug_allowed_common(DeviceState *dev, BusState *bus,
35                                                Error **errp)
36 {
37     DeviceClass *dc = DEVICE_GET_CLASS(dev);
38 
39     if (!dc->hotpluggable) {
40         error_setg(errp, "Device '%s' does not support hotplugging",
41                    object_get_typename(OBJECT(dev)));
42         return false;
43     }
44 
45     if (bus) {
46         if (!qbus_is_hotpluggable(bus)) {
47             error_setg(errp, "Bus '%s' does not support hotplugging",
48                        bus->name);
49             return false;
50         }
51     }
52 
53     return true;
54 }
55 
56 bool qdev_hotplug_allowed(DeviceState *dev, BusState *bus, Error **errp)
57 {
58     MachineState *machine;
59     MachineClass *mc;
60     Object *m_obj = qdev_get_machine();
61 
62     if (!qdev_hotplug_unplug_allowed_common(dev, bus, errp)) {
63         return false;
64     }
65 
66     if (object_dynamic_cast(m_obj, TYPE_MACHINE)) {
67         machine = MACHINE(m_obj);
68         mc = MACHINE_GET_CLASS(machine);
69         if (mc->hotplug_allowed) {
70             return mc->hotplug_allowed(machine, dev, errp);
71         }
72     }
73 
74     return true;
75 }
76 
77 bool qdev_hotunplug_allowed(DeviceState *dev, Error **errp)
78 {
79     return !qdev_unplug_blocked(dev, errp) &&
80            qdev_hotplug_unplug_allowed_common(dev, dev->parent_bus, errp);
81 }
82 
83 HotplugHandler *qdev_get_bus_hotplug_handler(DeviceState *dev)
84 {
85     if (dev->parent_bus) {
86         return dev->parent_bus->hotplug_handler;
87     }
88     return NULL;
89 }
90 
91 HotplugHandler *qdev_get_hotplug_handler(DeviceState *dev)
92 {
93     HotplugHandler *hotplug_ctrl = qdev_get_machine_hotplug_handler(dev);
94 
95     if (hotplug_ctrl == NULL && dev->parent_bus) {
96         hotplug_ctrl = qdev_get_bus_hotplug_handler(dev);
97     }
98     return hotplug_ctrl;
99 }
100 
101 /* can be used as ->unplug() callback for the simple cases */
102 void qdev_simple_device_unplug_cb(HotplugHandler *hotplug_dev,
103                                   DeviceState *dev, Error **errp)
104 {
105     qdev_unrealize(dev);
106 }
107