[PATCH RFC 2/4] xen/pvhvm: Introduce xen_pvhvm_kexec_shutdown()

[Vitaly Kuznetsov <vkuznets@redhat.com>]

PVHVM guest requires special actions before kexec. Register specific
xen_pvhvm_kexec_shutdown() handler for machine_ops.shutdown().

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
 arch/x86/xen/enlighten.c | 9 +++++++++
 arch/x86/xen/smp.c       | 9 +++++++++
 arch/x86/xen/smp.h       | 1 +
 3 files changed, 19 insertions(+)

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index a11af62..8074e4a 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1833,6 +1833,12 @@ static struct notifier_block xen_hvm_cpu_notifier = {
 	.notifier_call	= xen_hvm_cpu_notify,
 };
 
+static void xen_pvhvm_kexec_shutdown(void)
+{
+	xen_kexec_shutdown();
+	native_machine_shutdown();
+}
+
 static void __init xen_hvm_guest_init(void)
 {
 	init_hvm_pv_info();
@@ -1849,6 +1855,9 @@ static void __init xen_hvm_guest_init(void)
 	x86_init.irqs.intr_init = xen_init_IRQ;
 	xen_hvm_init_time_ops();
 	xen_hvm_init_mmu_ops();
+#ifdef CONFIG_KEXEC
+	machine_ops.shutdown = xen_pvhvm_kexec_shutdown;
+#endif
 }
 
 static uint32_t __init xen_hvm_platform(void)
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 7005974..35dcf39 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -18,6 +18,7 @@
 #include <linux/smp.h>
 #include <linux/irq_work.h>
 #include <linux/tick.h>
+#include <linux/kexec.h>
 
 #include <asm/paravirt.h>
 #include <asm/desc.h>
@@ -762,6 +763,14 @@ static void xen_hvm_cpu_die(unsigned int cpu)
 	native_cpu_die(cpu);
 }
 
+void xen_kexec_shutdown(void)
+{
+#ifdef CONFIG_KEXEC
+	if (!kexec_in_progress)
+		return;
+#endif
+}
+
 void __init xen_hvm_smp_init(void)
 {
 	if (!xen_have_vector_callback)
diff --git a/arch/x86/xen/smp.h b/arch/x86/xen/smp.h
index c7c2d89..1af0493 100644
--- a/arch/x86/xen/smp.h
+++ b/arch/x86/xen/smp.h
@@ -8,4 +8,5 @@ extern void xen_send_IPI_allbutself(int vector);
 extern void xen_send_IPI_all(int vector);
 extern void xen_send_IPI_self(int vector);
 
+extern void xen_kexec_shutdown(void);
 #endif
-- 
1.9.3