gallium: add flush_resource context function

r600g needs explicit flushing before DRI2 buffers are presented on the screen.

v2: add (stub) implementations for all drivers, fix frontbuffer flushing
v3: fix galahad

Signed-off-by: Marek Olšák <marek.olsak@amd.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/src/gallium/include/pipe/p_context.h b/src/gallium/include/pipe/p_context.h
index 69352f7260f..7d09ce4b19a 100644
--- a/src/gallium/include/pipe/p_context.h
+++ b/src/gallium/include/pipe/p_context.h
@@ -537,6 +537,19 @@ struct pipe_context {
                                unsigned sample_count,
                                unsigned sample_index,
                                float *out_value);
+
+   /**
+    * Flush the resource cache, so that the resource can be used
+    * by an external client. Possible usage:
+    * - flushing a resource before presenting it on the screen
+    * - flushing a resource if some other process or device wants to use it
+    * This shouldn't be used to flush caches if the resource is only managed
+    * by a single pipe_screen and is not shared with another process.
+    * (i.e. you shouldn't use it to flush caches explicitly if you want to e.g.
+    * use the resource for texturing)
+    */
+   void (*flush_resource)(struct pipe_context *ctx,
+                          struct pipe_resource *resource);
 };