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, 4 deletions

diff --git a/src/gallium/winsys/gdi/gdi_softpipe_winsys.c b/src/gallium/winsys/gdi/gdi_softpipe_winsys.c
index 2d961f70878..440666d835e 100644
--- a/src/gallium/winsys/gdi/gdi_softpipe_winsys.c
+++ b/src/gallium/winsys/gdi/gdi_softpipe_winsys.c
@@ -87,8 +87,7 @@ gdi_softpipe_buffer_unmap(struct pipe_winsys *winsys,
 
 
 static void
-gdi_softpipe_buffer_destroy(struct pipe_winsys *winsys,
-                            struct pipe_buffer *buf)
+gdi_softpipe_buffer_destroy(struct pipe_buffer *buf)
 {
    struct gdi_softpipe_buffer *oldBuf = gdi_softpipe_buffer(buf);
 
@@ -118,7 +117,7 @@ gdi_softpipe_buffer_create(struct pipe_winsys *winsys,
 {
    struct gdi_softpipe_buffer *buffer = CALLOC_STRUCT(gdi_softpipe_buffer);
 
-   buffer->base.refcount = 1;
+   pipe_reference_init(&buffer->base.reference, 1);
    buffer->base.alignment = alignment;
    buffer->base.usage = usage;
    buffer->base.size = size;
@@ -143,7 +142,7 @@ gdi_softpipe_user_buffer_create(struct pipe_winsys *winsys,
    if(!buffer)
       return NULL;
 
-   buffer->base.refcount = 1;
+   pipe_reference_init(&buffer->base.reference, 1);
    buffer->base.size = bytes;
    buffer->userBuffer = TRUE;
    buffer->data = ptr;