xen: Add suspend/resume support for PV on HVM guests.
Suspend/resume requires few different things on HVM: the suspend
hypercall is different; we don't need to save/restore memory related
settings; except the shared info page and the callback mechanism.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index b211a04..127c95c 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1262,13 +1262,15 @@
return 0;
}
-static void __init init_shared_info(void)
+void xen_hvm_init_shared_info(void)
{
+ int cpu;
struct xen_add_to_physmap xatp;
- struct shared_info *shared_info_page;
+ static struct shared_info *shared_info_page = 0;
- shared_info_page = (struct shared_info *)
- extend_brk(PAGE_SIZE, PAGE_SIZE);
+ if (!shared_info_page)
+ shared_info_page = (struct shared_info *)
+ extend_brk(PAGE_SIZE, PAGE_SIZE);
xatp.domid = DOMID_SELF;
xatp.idx = 0;
xatp.space = XENMAPSPACE_shared_info;
@@ -1278,7 +1280,17 @@
HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
- per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
+ /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
+ * page, we use it in the event channel upcall and in some pvclock
+ * related functions. We don't need the vcpu_info placement
+ * optimizations because we don't use any pv_mmu or pv_irq op on
+ * HVM.
+ * When xen_hvm_init_shared_info is run at boot time only vcpu 0 is
+ * online but xen_hvm_init_shared_info is run at resume time too and
+ * in that case multiple vcpus might be online. */
+ for_each_online_cpu(cpu) {
+ per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
+ }
}
static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self,
@@ -1308,7 +1320,7 @@
if (r < 0)
return;
- init_shared_info();
+ xen_hvm_init_shared_info();
if (xen_feature(XENFEAT_hvm_callback_vector))
xen_have_vector_callback = 1;