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().

3 files changed, 8 insertions, 10 deletions

diff --git a/src/gallium/winsys/xlib/xlib_brw_screen.c b/src/gallium/winsys/xlib/xlib_brw_screen.c
index 8e1bfab2f5..8329d3bbf7 100644
--- a/src/gallium/winsys/xlib/xlib_brw_screen.c
+++ b/src/gallium/winsys/xlib/xlib_brw_screen.c
@@ -57,10 +57,10 @@ buffer_from_surface(struct pipe_surface *surface)
 }
 
 struct aub_buffer {
+   struct pipe_reference reference;
    char *data;
    unsigned offset;
    unsigned size;
-   unsigned refcount;
    unsigned map_count;
    boolean dump_on_unmap;
 };
@@ -144,8 +144,7 @@ static void aub_buffer_unmap(struct pipe_winsys *winsys,
 
 
 static void
-aub_buffer_destroy(struct pipe_winsys *winsys,
-		   struct pipe_buffer *buf)
+aub_buffer_destroy(struct pipe_buffer *buf)
 {
    free(buf);
 }
@@ -189,7 +188,7 @@ aub_buffer_create(struct pipe_winsys *winsys,
    struct aub_pipe_winsys *iws = aub_pipe_winsys(winsys);
    struct aub_buffer *sbo = CALLOC_STRUCT(aub_buffer);
 
-   sbo->refcount = 1;
+   pipe_reference_init(&sbo->reference, 1);
 
    /* Could reuse buffers that are not referenced in current
     * batchbuffer.  Can't do that atm, so always reallocate:
diff --git a/src/gallium/winsys/xlib/xlib_cell.c b/src/gallium/winsys/xlib/xlib_cell.c
index 40bcdfe42a..a5dbdf30f6 100644
--- a/src/gallium/winsys/xlib/xlib_cell.c
+++ b/src/gallium/winsys/xlib/xlib_cell.c
@@ -243,7 +243,7 @@ xm_buffer_create(struct pipe_winsys *pws,
 {
    struct xm_buffer *buffer = CALLOC_STRUCT(xm_buffer);
 
-   buffer->base.refcount = 1;
+   pipe_reference_init(&buffer->base.reference, 1);
    buffer->base.alignment = alignment;
    buffer->base.usage = usage;
    buffer->base.size = size;
@@ -267,7 +267,7 @@ static struct pipe_buffer *
 xm_user_buffer_create(struct pipe_winsys *pws, void *ptr, unsigned bytes)
 {
    struct xm_buffer *buffer = CALLOC_STRUCT(xm_buffer);
-   buffer->base.refcount = 1;
+   pipe_reference_init(&buffer->base.reference, 1);
    buffer->base.size = bytes;
    buffer->userBuffer = TRUE;
    buffer->data = ptr;
diff --git a/src/gallium/winsys/xlib/xlib_softpipe.c b/src/gallium/winsys/xlib/xlib_softpipe.c
index 71f12b2b47..762ebd9847 100644
--- a/src/gallium/winsys/xlib/xlib_softpipe.c
+++ b/src/gallium/winsys/xlib/xlib_softpipe.c
@@ -207,8 +207,7 @@ xm_buffer_unmap(struct pipe_winsys *pws, struct pipe_buffer *buf)
 }
 
 static void
-xm_buffer_destroy(struct pipe_winsys *pws,
-                  struct pipe_buffer *buf)
+xm_buffer_destroy(struct pipe_buffer *buf)
 {
    struct xm_buffer *oldBuf = xm_buffer(buf);
 
@@ -338,7 +337,7 @@ xm_buffer_create(struct pipe_winsys *pws,
    }
 #endif
 
-   buffer->base.refcount = 1;
+   pipe_reference_init(&buffer->base.reference, 1);
    buffer->base.alignment = alignment;
    buffer->base.usage = usage;
    buffer->base.size = size;
@@ -359,7 +358,7 @@ static struct pipe_buffer *
 xm_user_buffer_create(struct pipe_winsys *pws, void *ptr, unsigned bytes)
 {
    struct xm_buffer *buffer = CALLOC_STRUCT(xm_buffer);
-   buffer->base.refcount = 1;
+   pipe_reference_init(&buffer->base.reference, 1);
    buffer->base.size = bytes;
    buffer->userBuffer = TRUE;
    buffer->data = ptr;