suspend: add infrastructure
This patch adds some infrastructure to handle suspend and resume to
qemu. First there are two functions to switch state and second there
is a suspend notifier:
* qemu_system_suspend_request is supposed to be called when the
guest asks for being be suspended, for example via ACPI.
* qemu_system_wakeup_request is supposed to be called on events
which should wake up the guest.
* qemu_register_suspend_notifier can be used to register a notifier
which will be called when the guest is suspended. Machine types
and device models can hook in there to modify state if needed.
* qemu_register_wakeup_notifier can be used to register a notifier
which will be called when the guest is woken up. Machine types
and device models can hook in there to modify state if needed.
* qemu_system_wakeup_enable can be used to enable/disable wakeup
events.
Signed-off-by: Gerd Hoffmann <[email protected]>
Signed-off-by: Anthony Liguori <[email protected]>
diff --git a/vl.c b/vl.c
index cd77852..90baa2a 100644
--- a/vl.c
+++ b/vl.c
@@ -1283,6 +1283,13 @@
static pid_t shutdown_pid;
static int powerdown_requested;
static int debug_requested;
+static int suspend_requested;
+static bool is_suspended;
+static NotifierList suspend_notifiers =
+ NOTIFIER_LIST_INITIALIZER(suspend_notifiers);
+static NotifierList wakeup_notifiers =
+ NOTIFIER_LIST_INITIALIZER(wakeup_notifiers);
+static uint32_t wakeup_reason_mask = ~0;
static RunState vmstop_requested = RUN_STATE_MAX;
int qemu_shutdown_requested_get(void)
@@ -1325,6 +1332,13 @@
return r;
}
+static int qemu_suspend_requested(void)
+{
+ int r = suspend_requested;
+ suspend_requested = 0;
+ return r;
+}
+
int qemu_powerdown_requested(void)
{
int r = powerdown_requested;
@@ -1398,6 +1412,56 @@
qemu_notify_event();
}
+static void qemu_system_suspend(void)
+{
+ pause_all_vcpus();
+ notifier_list_notify(&suspend_notifiers, NULL);
+ is_suspended = true;
+}
+
+void qemu_system_suspend_request(void)
+{
+ if (is_suspended) {
+ return;
+ }
+ suspend_requested = 1;
+ cpu_stop_current();
+ qemu_notify_event();
+}
+
+void qemu_register_suspend_notifier(Notifier *notifier)
+{
+ notifier_list_add(&suspend_notifiers, notifier);
+}
+
+void qemu_system_wakeup_request(WakeupReason reason)
+{
+ if (!is_suspended) {
+ return;
+ }
+ if (!(wakeup_reason_mask & (1 << reason))) {
+ return;
+ }
+ notifier_list_notify(&wakeup_notifiers, &reason);
+ reset_requested = 1;
+ qemu_notify_event();
+ is_suspended = false;
+}
+
+void qemu_system_wakeup_enable(WakeupReason reason, bool enabled)
+{
+ if (enabled) {
+ wakeup_reason_mask |= (1 << reason);
+ } else {
+ wakeup_reason_mask &= ~(1 << reason);
+ }
+}
+
+void qemu_register_wakeup_notifier(Notifier *notifier)
+{
+ notifier_list_add(&wakeup_notifiers, notifier);
+}
+
void qemu_system_killed(int signal, pid_t pid)
{
shutdown_signal = signal;
@@ -1438,6 +1502,9 @@
if (qemu_debug_requested()) {
vm_stop(RUN_STATE_DEBUG);
}
+ if (qemu_suspend_requested()) {
+ qemu_system_suspend();
+ }
if (qemu_shutdown_requested()) {
qemu_kill_report();
monitor_protocol_event(QEVENT_SHUTDOWN, NULL);
