[HVM] Save/restore: PV-on-HVM driver save/restore support

Signed-off-by: Zhai Edwin <edwin.zhai@intel.com>

tools/python/xen/lowlevel/xc/xc.c

@@ -467,6 +467,26 @@ static PyObject *pyxc_linux_build(XcObject *self,
     return pyxc_error_to_exception();
 }
 
+static PyObject *pyxc_get_hvm_param(XcObject *self,
+                                    PyObject *args,
+                                    PyObject *kwds)
+{
+    uint32_t dom;
+    int param;
+    unsigned long value;
+
+    static char *kwd_list[] = { "domid", "param", NULL }; 
+    if ( !PyArg_ParseTupleAndKeywords(args, kwds, "i|i", kwd_list,
+                                      &dom, &param) )
+        return NULL;
+
+    if ( xc_get_hvm_param(self->xc_handle, dom, param, &value) != 0 )
+        return pyxc_error_to_exception();
+
+    return Py_BuildValue("i", value);
+
+}
+
 static PyObject *pyxc_hvm_build(XcObject *self,
                                 PyObject *args,
                                 PyObject *kwds)
@@ -1225,6 +1245,14 @@ static PyMethodDef pyxc_methods[] = {
       " vcpus   [int, 1]:   Number of Virtual CPUS in domain.\n\n"
       "Returns: [int] 0 on success; -1 on error.\n" },
 
+    { "hvm_get_param", 
+      (PyCFunction)pyxc_get_hvm_param, 
+      METH_VARARGS | METH_KEYWORDS, "\n"
+      "get a parameter of HVM guest OS.\n"
+      " dom     [int]:      Identifier of domain to build into.\n"
+      " param   [int]:      No. of HVM param.\n"
+      "Returns: [int] value of the param.\n" },
+
     { "sched_id_get",
       (PyCFunction)pyxc_sched_id_get,
       METH_NOARGS, "\n"

tools/python/xen/xend/XendConstants.py

@@ -37,6 +37,13 @@ DOMAIN_SHUTDOWN_REASONS = {
 REVERSE_DOMAIN_SHUTDOWN_REASONS = \
     dict([(y, x) for x, y in DOMAIN_SHUTDOWN_REASONS.items()])
 
+HVM_PARAM_CALLBACK_IRQ = 0
+HVM_PARAM_STORE_PFN    = 1
+HVM_PARAM_STORE_EVTCHN = 2
+HVM_PARAM_PAE_ENABLED  = 4
+HVM_PARAM_IOREQ_PFN    = 5
+HVM_PARAM_BUFIOREQ_PFN = 6
+
 restart_modes = [
     "restart",
     "destroy",

tools/python/xen/xend/XendDomainInfo.py

@@ -448,11 +448,12 @@ class XendDomainInfo:
         self._removeVm('xend/previous_restart_time')
         self.storeDom("control/shutdown", reason)
 
-        ## shutdown hypercall for hvm domain desides xenstore write
-        if self.info.is_hvm():
-            for code in DOMAIN_SHUTDOWN_REASONS.keys():
-                if DOMAIN_SHUTDOWN_REASONS[code] == reason:
-                    break
+        ## HVM domain shutdown itself if has PV driver,
+        ## otherwise remote shutdown it
+        hvm_pvdrv = xc.hvm_get_param(self.domid, HVM_PARAM_CALLBACK_IRQ)
+        if self.info.is_hvm() and not hvm_pvdrv:
+            code = REVERSE_DOMAIN_SHUTDOWN_REASONS[reason]
+            log.info("HVM save:remote shutdown dom %d!", self.domid)
             xc.domain_shutdown(self.domid, code)