[HVM] Move shadow initialisation into domain-creation hypercall.

Allocate HVM guest memory in the libxc builder function rather
than in xend. Clean up fall out from these changes.

Todo: Fix ia64. Move PV builder to same model (it should allocate the
memory rather than xend doing so -- then it can avoid using
xc_get_pfn_list()).

Signed-off-by: Keir Fraser <keir@xensource.com>

tools/python/xen/xend/XendDomainInfo.py

@@ -1295,9 +1295,11 @@ class XendDomainInfo:
             shadow_cur = xc.shadow_mem_control(self.domid, shadow / 1024)
             self.info['shadow_memory'] = shadow_cur
 
-            # initial memory reservation
-            xc.domain_memory_increase_reservation(self.domid, reservation, 0,
-                                                  0)
+            # Initial memory reservation
+            if not (self._infoIsSet('image') and
+                    sxp.name(self.info['image']) == "hvm"):
+                xc.domain_memory_increase_reservation(
+                    self.domid, reservation, 0, 0)
 
             self._createChannels()
 

tools/python/xen/xend/image.py

@@ -478,22 +478,12 @@ class X86_HVM_ImageHandler(HVMImageHandler):
 
     def getRequiredAvailableMemory(self, mem_kb):
         # Add 8 MiB overhead for QEMU's video RAM.
-        return self.getRequiredInitialReservation(mem_kb) + 8192
+        return mem_kb + 8192
 
     def getRequiredInitialReservation(self, mem_kb):
-        page_kb = 4
-        # This was derived emperically:
-        #   2.4 MB overhead per 1024 MB RAM
-        #   + 4 to avoid low-memory condition
-        extra_mb = (2.4/1024) * (mem_kb/1024.0) + 4;
-        extra_pages = int( math.ceil( extra_mb*1024 / page_kb ))
-        return mem_kb + extra_pages * page_kb
+        return mem_kb
 
     def getRequiredShadowMemory(self, shadow_mem_kb, maxmem_kb):
-        # The given value is the configured value -- we need to include the
-        # overhead due to getRequiredInitialReservation.
-        maxmem_kb = self.getRequiredInitialReservation(maxmem_kb)
-
         # 256 pages (1MB) per vcpu,
         # plus 1 page per MiB of RAM for the P2M map,
         # plus 1 page per MiB of RAM to shadow the resident processes.