[RFC PATCH v3 3/4] vfio: Add vfio_prereg_listener_global_log_start/stop in nested stage

[Kunkun Jiang <jiangkunkun@huawei.com>]

In nested mode, we set up the stage 2 and stage 1 separately. In my
opinion, vfio_memory_prereg_listener is used for stage 2 and
vfio_memory_listener is used for stage 1. So it feels weird to call
the global_log_start/stop interface in vfio_memory_listener to switch
dirty tracking, although this won't cause any errors. Add
global_log_start/stop interface in vfio_memory_prereg_listener
can separate stage 2 from stage 1.

Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
---
 hw/vfio/common.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 149e535a75..6e004fc00f 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1209,6 +1209,17 @@ static void vfio_listener_log_global_start(MemoryListener *listener)
 {
     VFIOContainer *container = container_of(listener, VFIOContainer, listener);
 
+    /* For nested mode, vfio_prereg_listener is used to start dirty tracking */
+    if (container->iommu_type != VFIO_TYPE1_NESTING_IOMMU) {
+        vfio_set_dirty_page_tracking(container, true);
+    }
+}
+
+static void vfio_prereg_listener_log_global_start(MemoryListener *listener)
+{
+    VFIOContainer *container =
+        container_of(listener, VFIOContainer, prereg_listener);
+
     vfio_set_dirty_page_tracking(container, true);
 }
 
@@ -1216,6 +1227,17 @@ static void vfio_listener_log_global_stop(MemoryListener *listener)
 {
     VFIOContainer *container = container_of(listener, VFIOContainer, listener);
 
+    /* For nested mode, vfio_prereg_listener is used to stop dirty tracking */
+    if (container->iommu_type != VFIO_TYPE1_NESTING_IOMMU) {
+        vfio_set_dirty_page_tracking(container, false);
+    }
+}
+
+static void vfio_prereg_listener_log_global_stop(MemoryListener *listener)
+{
+    VFIOContainer *container =
+        container_of(listener, VFIOContainer, prereg_listener);
+
     vfio_set_dirty_page_tracking(container, false);
 }
 
@@ -1408,6 +1430,8 @@ static const MemoryListener vfio_memory_listener = {
 static MemoryListener vfio_memory_prereg_listener = {
     .region_add = vfio_prereg_listener_region_add,
     .region_del = vfio_prereg_listener_region_del,
+    .log_global_start = vfio_prereg_listener_log_global_start,
+    .log_global_stop = vfio_prereg_listener_log_global_stop,
     .log_sync = vfio_prereg_listener_log_sync,
 };
 
-- 
2.23.0