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 <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/sysemu.h b/sysemu.h
index 9d5ce3398f..af7381380e 100644
--- a/sysemu.h
+++ b/sysemu.h
@@ -38,7 +38,16 @@ void vm_start(void);
 void vm_stop(RunState state);
 void vm_stop_force_state(RunState state);
 
+typedef enum WakeupReason {
+    QEMU_WAKEUP_REASON_OTHER = 0,
+} WakeupReason;
+
 void qemu_system_reset_request(void);
+void qemu_system_suspend_request(void);
+void qemu_register_suspend_notifier(Notifier *notifier);
+void qemu_system_wakeup_request(WakeupReason reason);
+void qemu_system_wakeup_enable(WakeupReason reason, bool enabled);
+void qemu_register_wakeup_notifier(Notifier *notifier);
 void qemu_system_shutdown_request(void);
 void qemu_system_powerdown_request(void);
 void qemu_system_debug_request(void);