[RFC v1 1/4] red-parse-qxl: Extract the dmabuf fd from the scanout

[Vivek Kasireddy <vivek.kasireddy@xxxxxxxxx>]

If the scanout has a valid dmabuf fd, then it is extracted and a
copy (of the fd) is stored in the drawable.

Cc: Gerd Hoffmann <kraxel@xxxxxxxxxx>
Cc: Marc-André Lureau <marcandre.lureau@xxxxxxxxxx>
Cc: Dongwon Kim <dongwon.kim@xxxxxxxxx>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@xxxxxxxxx>
---
 server/red-parse-qxl.cpp | 8 ++++++++
 server/red-parse-qxl.h   | 1 +
 2 files changed, 9 insertions(+)

diff --git a/server/red-parse-qxl.cpp b/server/red-parse-qxl.cpp
index 68b9759d..8d9b82fb 100644
--- a/server/red-parse-qxl.cpp
+++ b/server/red-parse-qxl.cpp
@@ -1038,6 +1038,7 @@ static bool red_get_native_drawable(QXLInstance *qxl_instance, RedMemSlotInfo *s
                                     RedDrawable *red, QXLPHYSICAL addr, uint32_t flags)
 {
     QXLDrawable *qxl;
+    SpiceMsgDisplayGlScanoutUnix *scanout;
     int i;
 
     qxl = static_cast<QXLDrawable *>(memslot_get_virt(slots, addr, sizeof(*qxl), group_id));
@@ -1059,6 +1060,13 @@ static bool red_get_native_drawable(QXLInstance *qxl_instance, RedMemSlotInfo *s
         red_get_rect_ptr(&red->surfaces_rects[i], &qxl->surfaces_rects[i]);
     }
 
+    red->dmabuf_fd = 0;
+    scanout = red_qxl_get_gl_scanout(qxl_instance);
+    if (scanout != nullptr) {
+        red->dmabuf_fd = scanout->drm_dma_buf_fd;
+    }
+    red_qxl_put_gl_scanout(qxl_instance, scanout);
+
     red->type = qxl->type;
     switch (red->type) {
     case QXL_DRAW_ALPHA_BLEND:
diff --git a/server/red-parse-qxl.h b/server/red-parse-qxl.h
index 8bf0e2e3..dee50743 100644
--- a/server/red-parse-qxl.h
+++ b/server/red-parse-qxl.h
@@ -67,6 +67,7 @@ struct RedDrawable final: public RedQXLResource<RedDrawable> {
         SpiceWhiteness whiteness;
         SpiceComposite composite;
     } u;
+    int32_t dmabuf_fd;
 };
 
 struct RedUpdateCmd final: public RedQXLResource<RedUpdateCmd> {
-- 
2.37.2