xref: /openbmc/qemu/hw/core/reset.c (revision 954a6c4f)
1 /*
2  *  Reset handlers.
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  * Copyright (c) 2016 Red Hat, Inc.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "qemu/queue.h"
28 #include "sysemu/reset.h"
29 
30 /* reset/shutdown handler */
31 
32 typedef struct QEMUResetEntry {
33     QTAILQ_ENTRY(QEMUResetEntry) entry;
34     QEMUResetHandler *func;
35     void *opaque;
36     bool skip_on_snapshot_load;
37 } QEMUResetEntry;
38 
39 static QTAILQ_HEAD(, QEMUResetEntry) reset_handlers =
40     QTAILQ_HEAD_INITIALIZER(reset_handlers);
41 
42 void qemu_register_reset(QEMUResetHandler *func, void *opaque)
43 {
44     QEMUResetEntry *re = g_new0(QEMUResetEntry, 1);
45 
46     re->func = func;
47     re->opaque = opaque;
48     QTAILQ_INSERT_TAIL(&reset_handlers, re, entry);
49 }
50 
51 void qemu_register_reset_nosnapshotload(QEMUResetHandler *func, void *opaque)
52 {
53     QEMUResetEntry *re = g_new0(QEMUResetEntry, 1);
54 
55     re->func = func;
56     re->opaque = opaque;
57     re->skip_on_snapshot_load = true;
58     QTAILQ_INSERT_TAIL(&reset_handlers, re, entry);
59 }
60 
61 void qemu_unregister_reset(QEMUResetHandler *func, void *opaque)
62 {
63     QEMUResetEntry *re;
64 
65     QTAILQ_FOREACH(re, &reset_handlers, entry) {
66         if (re->func == func && re->opaque == opaque) {
67             QTAILQ_REMOVE(&reset_handlers, re, entry);
68             g_free(re);
69             return;
70         }
71     }
72 }
73 
74 void qemu_devices_reset(ShutdownCause reason)
75 {
76     QEMUResetEntry *re, *nre;
77 
78     /* reset all devices */
79     QTAILQ_FOREACH_SAFE(re, &reset_handlers, entry, nre) {
80         if (reason == SHUTDOWN_CAUSE_SNAPSHOT_LOAD &&
81             re->skip_on_snapshot_load) {
82             continue;
83         }
84         re->func(re->opaque);
85     }
86 }
87 
88