memory: support stateless memory listeners

Current memory listeners are incremental; that is, they are expected to
maintain their own state, and receive callbacks for changes to that state.

This patch adds support for stateless listeners; these work by receiving
a ->begin() callback (which tells them that new state is coming), a
sequence of ->region_add() and ->region_nop() callbacks, and then a
->commit() callback which signifies the end of the new state.  They should
ignore ->region_del() callbacks.

Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/memory.h b/memory.h
index bc9600b4..b7bccd1 100644
--- a/memory.h
+++ b/memory.h
@@ -180,8 +180,11 @@ typedef struct MemoryListener MemoryListener;
  * Use with memory_listener_register() and memory_listener_unregister().
  */
 struct MemoryListener {
+    void (*begin)(MemoryListener *listener);
+    void (*commit)(MemoryListener *listener);
     void (*region_add)(MemoryListener *listener, MemoryRegionSection *section);
     void (*region_del)(MemoryListener *listener, MemoryRegionSection *section);
+    void (*region_nop)(MemoryListener *listener, MemoryRegionSection *section);
     void (*log_start)(MemoryListener *listener, MemoryRegionSection *section);
     void (*log_stop)(MemoryListener *listener, MemoryRegionSection *section);
     void (*log_sync)(MemoryListener *listener, MemoryRegionSection *section);