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, 3 insertions, 8 deletions

diff --git a/src/gallium/drivers/nv30/nv30_transfer.c b/src/gallium/drivers/nv30/nv30_transfer.c
index 6367374a616..8b915b35bd4 100644
--- a/src/gallium/drivers/nv30/nv30_transfer.c
+++ b/src/gallium/drivers/nv30/nv30_transfer.c
@@ -64,7 +64,6 @@ nv30_transfer_new(struct pipe_screen *pscreen, struct pipe_texture *pt,
 	if (!tx)
 		return NULL;
 
-	tx->base.refcount = 1;
 	pipe_texture_reference(&tx->base.texture, pt);
 	tx->base.format = pt->format;
 	tx->base.x = x;
@@ -138,12 +137,12 @@ nv30_transfer_new(struct pipe_screen *pscreen, struct pipe_texture *pt,
 }
 
 static void
-nv30_transfer_del(struct pipe_screen *pscreen, struct pipe_transfer **pptx)
+nv30_transfer_del(struct pipe_transfer *ptx)
 {
-	struct pipe_transfer *ptx = *pptx;
 	struct nv30_transfer *tx = (struct nv30_transfer *)ptx;
 
 	if (!tx->direct && ptx->usage != PIPE_TRANSFER_READ) {
+		struct pipe_screen *pscreen = ptx->texture->screen;
 		struct nv30_screen *nvscreen = nv30_screen(pscreen);
 		struct pipe_surface *dst;
 
@@ -160,10 +159,6 @@ nv30_transfer_del(struct pipe_screen *pscreen, struct pipe_transfer **pptx)
 		pipe_surface_reference(&dst, NULL);
 	}
 
-	*pptx = NULL;
-	if (--ptx->refcount)
-		return;
-
 	pipe_surface_reference(&tx->surface, NULL);
 	pipe_texture_reference(&ptx->texture, NULL);
 	FREE(ptx);
@@ -195,7 +190,7 @@ void
 nv30_screen_init_transfer_functions(struct pipe_screen *pscreen)
 {
 	pscreen->get_tex_transfer = nv30_transfer_new;
-	pscreen->tex_transfer_release = nv30_transfer_del;
+	pscreen->tex_transfer_destroy = nv30_transfer_del;
 	pscreen->transfer_map = nv30_transfer_map;
 	pscreen->transfer_unmap = nv30_transfer_unmap;
 }