memory: introduce memory_region_notify_one()

Generalizing the notify logic in memory_region_notify_iommu() into a
single function. This can be further used in customized replay()
functions for IOMMUs.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: \"Michael S. Tsirkin\" <mst@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1491562755-23867-5-git-send-email-peterx@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
diff --git a/include/exec/memory.h b/include/exec/memory.h
index fb7dff3..055b3a8 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -688,6 +688,21 @@
                                 IOMMUTLBEntry entry);
 
 /**
+ * memory_region_notify_one: notify a change in an IOMMU translation
+ *                           entry to a single notifier
+ *
+ * This works just like memory_region_notify_iommu(), but it only
+ * notifies a specific notifier, not all of them.
+ *
+ * @notifier: the notifier to be notified
+ * @entry: the new entry in the IOMMU translation table.  The entry
+ *         replaces all old entries for the same virtual I/O address range.
+ *         Deleted entries have .@perm == 0.
+ */
+void memory_region_notify_one(IOMMUNotifier *notifier,
+                              IOMMUTLBEntry *entry);
+
+/**
  * memory_region_register_iommu_notifier: register a notifier for changes to
  * IOMMU translation entries.
  *