gallium: Unify reference counting.

The core reference counting code is centralized in p_refcnt.h.

This has some consequences related to struct pipe_buffer:

* The screen member of struct pipe_buffer must be initialized, or
  pipe_buffer_reference() will crash trying to destroy a buffer with reference
  count 0. u_simple_screen takes care of this, but I may have missed some of
  the drivers not using it.
* Except for rare exceptions deep in winsys code, buffers must always be
  allocated via pipe_buffer_create() or via screen->*buffer_create() rather
  than via winsys->*buffer_create().

2 files changed, 7 insertions, 6 deletions

diff --git a/src/gallium/winsys/drm/radeon/radeon_buffer.c b/src/gallium/winsys/drm/radeon/radeon_buffer.c
index 79b8f777ca8..b3582e3314a 100644
--- a/src/gallium/winsys/drm/radeon/radeon_buffer.c
+++ b/src/gallium/winsys/drm/radeon/radeon_buffer.c
@@ -63,7 +63,7 @@ static struct pipe_buffer *radeon_buffer_create(struct pipe_winsys *ws,
         return NULL;
     }
 
-    radeon_buffer->base.refcount = 1;
+    pipe_reference_init(&radeon_buffer->base.reference, 1);
     radeon_buffer->base.alignment = alignment;
     radeon_buffer->base.usage = usage;
     radeon_buffer->base.size = size;
@@ -104,7 +104,7 @@ static struct pipe_buffer *radeon_buffer_user_create(struct pipe_winsys *ws,
     return &radeon_buffer->base;
 }
 
-static void radeon_buffer_del(struct pipe_winsys *ws, struct pipe_buffer *buffer)
+static void radeon_buffer_del(struct pipe_buffer *buffer)
 {
     struct radeon_pipe_buffer *radeon_buffer = (struct radeon_pipe_buffer*)buffer;
 
@@ -207,7 +207,7 @@ static struct pipe_buffer *radeon_buffer_from_handle(struct radeon_screen *radeo
         radeon_bo_unref(bo);
         return NULL;
     }
-    radeon_buffer->base.refcount = 1;
+    pipe_reference_init(&radeon_buffer->base.reference, 1);
     radeon_buffer->base.usage = PIPE_BUFFER_USAGE_PIXEL;
     radeon_buffer->bo = bo;
     return &radeon_buffer->base;
@@ -242,10 +242,10 @@ struct pipe_surface *radeon_surface_from_handle(struct radeon_context *radeon_co
 
     pt = pipe_screen->texture_blanket(pipe_screen, &tmpl, &pitch, pb);
     if (pt == NULL) {
-        pipe_buffer_reference(pipe_screen, &pb, NULL);
+        pipe_buffer_reference(&pb, NULL);
     }
     ps = pipe_screen->get_tex_surface(pipe_screen, pt, 0, 0, 0,
                                       PIPE_BUFFER_USAGE_GPU_WRITE);
     return ps;
 }
-#endif
\ No newline at end of file
+#endif
diff --git a/src/gallium/winsys/drm/radeon/radeon_drm.c b/src/gallium/winsys/drm/radeon/radeon_drm.c
index 21f2a62e0fe..016634c8fd3 100644
--- a/src/gallium/winsys/drm/radeon/radeon_drm.c
+++ b/src/gallium/winsys/drm/radeon/radeon_drm.c
@@ -84,7 +84,8 @@ struct pipe_buffer* radeon_buffer_from_handle(struct pipe_screen* screen,
         return NULL;
     }
 
-    radeon_buffer->base.refcount = 1;
+    pipe_reference_init(&radeon_buffer->base.reference, 1);
+    radeon_buffer->base.screen = screen;
     radeon_buffer->base.usage = PIPE_BUFFER_USAGE_PIXEL;
     radeon_buffer->bo = bo;
     return &radeon_buffer->base;