memory: export AddressSpace

The DMA API will use an AddressSpace to differentiate among different
initiators.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

memory.c

@@ -216,17 +216,8 @@ struct FlatView {
     unsigned nr_allocated;
 };
 
-typedef struct AddressSpace AddressSpace;
 typedef struct AddressSpaceOps AddressSpaceOps;
 
-/* A system address space - I/O, memory, etc. */
-struct AddressSpace {
-    MemoryRegion *root;
-    FlatView *current_map;
-    int ioeventfd_nb;
-    MemoryRegionIoeventfd *ioeventfds;
-};
-
 #define FOR_EACH_FLAT_RANGE(var, view)          \
     for (var = (view)->ranges; var < (view)->ranges + (view)->nr; ++var)
 
@@ -1510,7 +1501,7 @@ void memory_listener_unregister(MemoryListener *listener)
     QTAILQ_REMOVE(&memory_listeners, listener, link);
 }
 
-static void address_space_init(AddressSpace *as, MemoryRegion *root)
+void address_space_init(AddressSpace *as, MemoryRegion *root)
 {
     memory_region_transaction_begin();
     as->root = root;

memory.h

@@ -157,6 +157,19 @@ struct MemoryRegionPortio {
 
 #define PORTIO_END_OF_LIST() { }
 
+typedef struct AddressSpace AddressSpace;
+
+/**
+ * AddressSpace: describes a mapping of addresses to #MemoryRegion objects
+ */
+struct AddressSpace {
+    /* All fields are private. */
+    MemoryRegion *root;
+    struct FlatView *current_map;
+    int ioeventfd_nb;
+    struct MemoryRegionIoeventfd *ioeventfds;
+};
+
 typedef struct MemoryRegionSection MemoryRegionSection;
 
 /**
@@ -776,6 +789,14 @@ void memory_global_dirty_log_stop(void);
 
 void mtree_info(fprintf_function mon_printf, void *f);
 
+/**
+ * address_space_init: initializes an address space
+ *
+ * @as: an uninitialized #AddressSpace
+ * @root: a #MemoryRegion that routes addesses for the address space
+ */
+void address_space_init(AddressSpace *as, MemoryRegion *root);
+
 #endif
 
 #endif