hw/core/reset.c

   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