gbm/dri: Flush after unmap

Drivers may queue dma operations on the context at unmap time so we need
to flush to make sure the data gets to the bo. Ideally the application
would take care of this, but since there appears to be no exported gbm
flush functionality we need to explicitly flush at unmap time.

This fixes a problem where kmscube on vmwgfx in rgba textured mode would
render using an uninitialized texture rather than the intended
rgba pattern.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Eric Anholt <eric@anholt.net>

diff --git a/src/gbm/backends/dri/gbm_dri.c b/src/gbm/backends/dri/gbm_dri.c
index 6b89229cdc0e3d024153e00080b0fa0aa6306d8a..189a8fcde5a176d2f0415252fb73725eff46010d 100644 (file)
--- a/src/gbm/backends/dri/gbm_dri.c
+++ b/src/gbm/backends/dri/gbm_dri.c
@@ -253,7 +253,7 @@ struct dri_extension_match {
 };
 
 static struct dri_extension_match dri_core_extensions[] = {
-   { __DRI2_FLUSH, 1, offsetof(struct gbm_dri_device, flush) },
+   { __DRI2_FLUSH, 4, offsetof(struct gbm_dri_device, flush) },
    { __DRI_IMAGE, 1, offsetof(struct gbm_dri_device, image) },
    { __DRI2_FENCE, 1, offsetof(struct gbm_dri_device, fence), 1 },
    { __DRI2_INTEROP, 1, offsetof(struct gbm_dri_device, interop), 1 },
@@ -1239,6 +1239,13 @@ gbm_dri_bo_unmap(struct gbm_bo *_bo, void *map_data)
       return;
 
    dri->image->unmapImage(dri->context, bo->image, map_data);
+
+   /*
+    * Not all DRI drivers use direct maps. They may queue up DMA operations
+    * on the mapping context. Since there is no explicit gbm flush
+    * mechanism, we need to flush here.
+    */
+   dri->flush->flush_with_flags(dri->context, NULL, __DRI2_FLUSH_CONTEXT, 0);
 }