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().

1 files changed, 2 insertions, 1 deletions

diff --git a/src/gallium/drivers/nv30/nv30_fragprog.c b/src/gallium/drivers/nv30/nv30_fragprog.c
index 320ba3f4bf..0da392fed3 100644
--- a/src/gallium/drivers/nv30/nv30_fragprog.c
+++ b/src/gallium/drivers/nv30/nv30_fragprog.c
@@ -834,6 +834,7 @@ nv30_fragprog_validate(struct nv30_context *nv30)
 	struct nv30_fragment_program *fp = nv30->fragprog;
 	struct pipe_buffer *constbuf =
 		nv30->constbuf[PIPE_SHADER_FRAGMENT];
+	struct pipe_screen *screen = nv30->pipe.screen;
 	struct pipe_winsys *ws = nv30->pipe.winsys;
 	struct nouveau_stateobj *so;
 	boolean new_consts = FALSE;
@@ -849,7 +850,7 @@ nv30_fragprog_validate(struct nv30_context *nv30)
 		return FALSE;
 	}
 
-	fp->buffer = ws->buffer_create(ws, 0x100, 0, fp->insn_len * 4);
+	fp->buffer = screen->buffer_create(screen, 0x100, 0, fp->insn_len * 4);
 	nv30_fragprog_upload(nv30, fp);
 
 	so = so_new(8, 1);