[HVM] HVM is now a flag parameter to domain-creation hypercall.

This cleans up HVM start-of-day in Xen and means that the
HVM status of a domain is maintained from cradle to grave.
Signed-off-by: Keir Fraser <keir@xensource.com>

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

@@ -65,18 +65,17 @@ static PyObject *pyxc_domain_create(XcObject *self,
                                     PyObject *args,
                                     PyObject *kwds)
 {
-    uint32_t dom = 0;
-    int      ret, i;
-    uint32_t ssidref = 0;
+    uint32_t dom = 0, ssidref = 0, flags = 0;
+    int      ret, i, hvm = 0;
     PyObject *pyhandle = NULL;
     xen_domain_handle_t handle = { 
         0xde, 0xad, 0xbe, 0xef, 0xde, 0xad, 0xbe, 0xef,
         0xde, 0xad, 0xbe, 0xef, 0xde, 0xad, 0xbe, 0xef };
 
-    static char *kwd_list[] = { "domid", "ssidref", "handle", NULL };
+    static char *kwd_list[] = { "domid", "ssidref", "handle", "hvm", NULL };
 
-    if ( !PyArg_ParseTupleAndKeywords(args, kwds, "|iiO", kwd_list,
-                                      &dom, &ssidref, &pyhandle))
+    if ( !PyArg_ParseTupleAndKeywords(args, kwds, "|iiOi", kwd_list,
+                                      &dom, &ssidref, &pyhandle, &hvm))
         return NULL;
 
     if ( pyhandle != NULL )
@@ -94,7 +93,11 @@ static PyObject *pyxc_domain_create(XcObject *self,
         }
     }
 
-    if ( (ret = xc_domain_create(self->xc_handle, ssidref, handle, &dom)) < 0 )
+    if ( hvm )
+        flags |= XEN_DOMCTL_CDF_hvm_guest;
+
+    if ( (ret = xc_domain_create(self->xc_handle, ssidref,
+                                 handle, flags, &dom)) < 0 )
         return PyErr_SetFromErrno(xc_error);
 
     return PyInt_FromLong(dom);

tools/python/xen/xend/XendDomainInfo.py

@@ -1198,10 +1198,20 @@ class XendDomainInfo:
 
         log.debug('XendDomainInfo.constructDomain')
 
+        hvm = (self._infoIsSet('image') and
+               sxp.name(self.info['image']) == "hvm")
+        if hvm:
+            info = xc.xeninfo()
+            if not 'hvm' in info['xen_caps']:
+                raise VmError("HVM guest support is unavailable: is VT/AMD-V "
+                              "supported by your CPU and enabled in your "
+                              "BIOS?")
+
         self.domid = xc.domain_create(
             domid = 0,
             ssidref = security.get_security_info(self.info, 'ssidref'),
-            handle = uuid.fromString(self.info['uuid']))
+            handle = uuid.fromString(self.info['uuid']),
+            hvm = int(hvm))
 
         if self.domid < 0:
             raise VmError('Creating domain failed: name=%s' %