Internal interfaces for memory API

get_system_memory() provides the root of the memory hierarchy.

This interface is intended to be private between memory.c and exec.c.
If this file is included elsewhere, it should be regarded as a bug (or
TODO item).  However, it will be temporarily needed for the conversion
to hierarchical memory routing.

Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

exec-memory.h

@@ -0,0 +1,36 @@
+/*
+ * Internal memory managment interfaces
+ *
+ * Copyright 2011 Red Hat, Inc. and/or its affiliates
+ *
+ * Authors:
+ *  Avi Kivity <avi@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef EXEC_MEMORY_H
+#define EXEC_MEMORY_H
+
+/*
+ * Internal interfaces between memory.c/exec.c/vl.c.  Do not #include unless
+ * you're one of them.
+ */
+
+#include "memory.h"
+
+#ifndef CONFIG_USER_ONLY
+
+/* Get the root memory region.  This interface should only be used temporarily
+ * until a proper bus interface is available.
+ */
+MemoryRegion *get_system_memory(void);
+
+/* Set the root memory region.  This region is the system memory map. */
+void set_system_memory_map(MemoryRegion *mr);
+
+#endif
+
+#endif

memory.c

@@ -12,6 +12,7 @@
  */
 
 #include "memory.h"
+#include "exec-memory.h"
 #include <assert.h>
 
 typedef struct AddrRange AddrRange;
@@ -703,3 +704,9 @@ void memory_region_del_subregion(MemoryRegion *mr,
     QTAILQ_REMOVE(&mr->subregions, subregion, subregions_link);
     memory_region_update_topology();
 }
+
+void set_system_memory_map(MemoryRegion *mr)
+{
+    root_memory_region = mr;
+    memory_region_update_topology();
+}