Add nomigrate config option to disable migration/restore

The new nomigrate option can be set to non-zero in vm.cfg
(for both hvm and pvm) to disallow a guest from being
migrated or restored.  (Save is still allowed for the purpose
of checkpointing.)  The option persists into a save file
and is also communicated into the hypervisor, the latter
for the purposes of a to-be-added hypercall for communicating
to guests that migration is disallowed (which will be
used initially for userland TSC-related sensing, but may
find other uses).

Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
index fb60344505..45337a6dae 100644
--- a/xen/include/public/domctl.h
+++ b/xen/include/public/domctl.h
@@ -653,6 +653,12 @@ typedef struct xen_domctl_hvmcontext_partial {
 } xen_domctl_hvmcontext_partial_t;
 DEFINE_XEN_GUEST_HANDLE(xen_domctl_hvmcontext_partial_t);
 
+#define XEN_DOMCTL_disable_migrate    58
+typedef struct xen_domctl_disable_migrate {
+    uint32_t disable; /* IN: 1: disable migration and restore */
+} xen_domctl_disable_migrate_t;
+
+
 #define XEN_DOMCTL_gdbsx_guestmemio     1000 /* guest mem io */
 struct xen_domctl_gdbsx_memio {
     uint64_aligned_t pgd3val;/* optional: init_mm.pgd[3] value */
@@ -703,6 +709,7 @@ struct xen_domctl {
         struct xen_domctl_arch_setup        arch_setup;
         struct xen_domctl_settimeoffset     settimeoffset;
         struct xen_domctl_set_tsc_native    set_tsc_native;
+        struct xen_domctl_disable_migrate   disable_migrate;
         struct xen_domctl_real_mode_area    real_mode_area;
         struct xen_domctl_hvmcontext        hvmcontext;
         struct xen_domctl_hvmcontext_partial hvmcontext_partial;