memory: MemoryRegion: factor out subregion add functionality

Split off the core looping code that actually adds subregions into
it's own fn. This prepares support for Memory Region qomification
where setting the MR address or parent via QOM will back onto this more
minimal function.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
[Rename new function. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 12 insertions, 6 deletions

diff --git a/memory.c b/memory.c
index 3811bd1..15f63e8 100644
--- a/memory.c
+++ b/memory.c
@@ -1423,18 +1423,15 @@ void memory_region_del_eventfd(MemoryRegion *mr,
     memory_region_transaction_commit();
 }
 
-static void memory_region_add_subregion_common(MemoryRegion *mr,
-                                               hwaddr offset,
-                                               MemoryRegion *subregion)
+static void memory_region_update_parent_subregions(MemoryRegion *subregion)
 {
+    hwaddr offset = subregion->addr;
+    MemoryRegion *mr = subregion->parent;
     MemoryRegion *other;
 
     memory_region_transaction_begin();
 
-    assert(!subregion->parent);
     memory_region_ref(subregion);
-    subregion->parent = mr;
-    subregion->addr = offset;
     QTAILQ_FOREACH(other, &mr->subregions, subregions_link) {
         if (subregion->may_overlap || other->may_overlap) {
             continue;
@@ -1468,6 +1465,15 @@ done:
     memory_region_transaction_commit();
 }
 
+static void memory_region_add_subregion_common(MemoryRegion *mr,
+                                               hwaddr offset,
+                                               MemoryRegion *subregion)
+{
+    assert(!subregion->parent);
+    subregion->parent = mr;
+    subregion->addr = offset;
+    memory_region_update_parent_subregions(subregion);
+}
 
 void memory_region_add_subregion(MemoryRegion *mr,
                                  hwaddr offset,