Add a function to be called when an async graphic update is done.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/ui/console.h    | 1 +
 hw/display/qxl-render.c | 9 +++++++--
 ui/console.c            | 4 ++++
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/include/ui/console.h b/include/ui/console.h
index d2b6c46a62..fc21621656 100644
--- a/include/ui/console.h
+++ b/include/ui/console.h
@@ -390,6 +390,7 @@ void graphic_console_set_hwops(QemuConsole *con,
 void graphic_console_close(QemuConsole *con);
 
 bool graphic_hw_update(QemuConsole *con);
+void graphic_hw_update_done(QemuConsole *con);
 void graphic_hw_invalidate(QemuConsole *con);
 void graphic_hw_text_update(QemuConsole *con, console_ch_t *chardata);
 void graphic_hw_gl_block(QemuConsole *con, bool block);
diff --git a/hw/display/qxl-render.c b/hw/display/qxl-render.c
index 62574173a2..08722d2833 100644
--- a/hw/display/qxl-render.c
+++ b/hw/display/qxl-render.c
@@ -106,7 +106,7 @@ static void qxl_render_update_area_unlocked(PCIQXLDevice *qxl)
                                                 qxl->guest_primary.surface.mem,
                                                 MEMSLOT_GROUP_GUEST);
         if (!qxl->guest_primary.data) {
-            return;
+            goto end;
         }
         qxl_set_rect_to_surface(qxl, &qxl->dirty[0]);
         qxl->num_dirty_rects = 1;
@@ -134,7 +134,7 @@ static void qxl_render_update_area_unlocked(PCIQXLDevice *qxl)
     }
 
     if (!qxl->guest_primary.data) {
-        return;
+        goto end;
     }
     for (i = 0; i < qxl->num_dirty_rects; i++) {
         if (qemu_spice_rect_is_empty(qxl->dirty+i)) {
@@ -155,6 +155,11 @@ static void qxl_render_update_area_unlocked(PCIQXLDevice *qxl)
                        qxl->dirty[i].bottom - qxl->dirty[i].top);
     }
     qxl->num_dirty_rects = 0;
+
+end:
+    if (qxl->render_update_cookie_num == 0) {
+        graphic_hw_update_done(qxl->ssd.dcl.con);
+    }
 }
 
 /*
diff --git a/ui/console.c b/ui/console.c
index 0774cd3366..29234605a7 100644
--- a/ui/console.c
+++ b/ui/console.c
@@ -256,6 +256,10 @@ static void gui_setup_refresh(DisplayState *ds)
     ds->have_text = have_text;
 }
 
+void graphic_hw_update_done(QemuConsole *con)
+{
+}
+
 bool graphic_hw_update(QemuConsole *con)
 {
     if (!con) {
-- 
2.17.0.rc1.1.g4c4f2b46a3