arm,arm64/xen: introduce HYPERVISOR_suspend()

Introduce HYPERVISOR_suspend() and a few additional empty stubs for
Xen arch specific functions called by drivers/xen/manage.c.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

arch/arm/include/asm/xen/hypercall.h

@@ -34,6 +34,7 @@
 #define _ASM_ARM_XEN_HYPERCALL_H
 
 #include <xen/interface/xen.h>
+#include <xen/interface/sched.h>
 
 long privcmd_call(unsigned call, unsigned long a1,
 		unsigned long a2, unsigned long a3,
@@ -50,6 +51,15 @@ int HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args);
 int HYPERVISOR_tmem_op(void *arg);
 int HYPERVISOR_multicall(struct multicall_entry *calls, uint32_t nr);
 
+static inline int
+HYPERVISOR_suspend(unsigned long start_info_mfn)
+{
+	struct sched_shutdown r = { .reason = SHUTDOWN_suspend };
+
+	/* start_info_mfn is unused on ARM */
+	return HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
+}
+
 static inline void
 MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va,
 			unsigned int new_val, unsigned long flags)

arch/arm/xen/enlighten.c

@@ -339,6 +339,14 @@ static int __init xen_pm_init(void)
 }
 late_initcall(xen_pm_init);
 
+
+/* empty stubs */
+void xen_arch_pre_suspend(void) { }
+void xen_arch_post_suspend(int suspend_cancelled) { }
+void xen_timer_resume(void) { }
+void xen_arch_resume(void) { }
+
+
 /* In the hypervisor.S file. */
 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);