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, 3 deletions

diff --git a/src/gallium/auxiliary/pipebuffer/pb_bufmgr_mm.c b/src/gallium/auxiliary/pipebuffer/pb_bufmgr_mm.c
index 85ff3a09de4..9b0f77bedb4 100644
--- a/src/gallium/auxiliary/pipebuffer/pb_bufmgr_mm.c
+++ b/src/gallium/auxiliary/pipebuffer/pb_bufmgr_mm.c
@@ -97,11 +97,11 @@ mm_buffer_destroy(struct pb_buffer *buf)
    struct mm_buffer *mm_buf = mm_buffer(buf);
    struct mm_pb_manager *mm = mm_buf->mgr;
    
-   assert(buf->base.refcount == 0);
+   assert(mm_buf->base.base.reference.count == 0);
    
    pipe_mutex_lock(mm->mutex);
    u_mmFreeMem(mm_buf->block);
-   FREE(buf);
+   FREE(mm_buf);
    pipe_mutex_unlock(mm->mutex);
 }
 
@@ -189,7 +189,7 @@ mm_bufmgr_create_buffer(struct pb_manager *mgr,
       return NULL;
    }
 
-   mm_buf->base.base.refcount = 1;
+   pipe_reference_init(&mm_buf->base.base.reference, 1);
    mm_buf->base.base.alignment = desc->alignment;
    mm_buf->base.base.usage = desc->usage;
    mm_buf->base.base.size = size;