i965/meta: Don't pollute the renderbuffer namespace

tl;dr: For many types of GL object, we can *NEVER* use the Gen function.

In OpenGL ES (all versions!) and OpenGL compatibility profile,
applications don't have to call Gen functions.  The GL spec is very
clear about how you can mix-and-match generated names and non-generated
names: you can use any name you want for a particular object type until
you call the Gen function for that object type.

Here's the problem scenario:

 - Application calls a meta function that generates a name.  The first
   Gen will probably return 1.

 - Application decides to use the same name for an object of the same
   type without calling Gen.  Many demo programs use names 1, 2, 3,
   etc. without calling Gen.

 - Application calls the meta function again, and the meta function
   replaces the data.  The application's data is lost, and the app
   fails.  Have fun debugging that.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92363
Reviewed-by: Anuj Phogat <anuj.phogat@gmail.com>

1 files changed, 6 insertions, 13 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_meta_updownsample.c b/src/mesa/drivers/dri/i965/brw_meta_updownsample.c
index 149f4bc..e90e6b1 100644
--- a/src/mesa/drivers/dri/i965/brw_meta_updownsample.c
+++ b/src/mesa/drivers/dri/i965/brw_meta_updownsample.c
@@ -29,6 +29,7 @@
 #include "main/buffers.h"
 #include "main/enums.h"
 #include "main/fbobject.h"
+#include "main/renderbuffer.h"
 
 #include "drivers/common/meta.h"
 
@@ -51,18 +52,10 @@ brw_get_rb_for_slice(struct brw_context *brw,
                      unsigned level, unsigned layer, bool flat)
 {
    struct gl_context *ctx = &brw->ctx;
-   GLuint rbo;
-   struct gl_renderbuffer *rb;
-   struct intel_renderbuffer *irb;
-
-   /* This turns the CreateRenderbuffers name into an actual struct
-    * intel_renderbuffer.
-    */
-   _mesa_CreateRenderbuffers(1, &rbo);
-
-   rb = _mesa_lookup_renderbuffer(ctx, rbo);
-   irb = intel_renderbuffer(rb);
+   struct gl_renderbuffer *rb = ctx->Driver.NewRenderbuffer(ctx, 0xDEADBEEF);
+   struct intel_renderbuffer *irb = intel_renderbuffer(rb);
 
+   rb->RefCount = 1;
    rb->Format = mt->format;
    rb->_BaseFormat = _mesa_get_format_base_format(mt->format);
 
@@ -140,8 +133,8 @@ brw_meta_updownsample(struct brw_context *brw,
                          dst_mt->logical_width0, dst_mt->logical_height0,
                          blit_bit, GL_NEAREST);
 
-   _mesa_DeleteRenderbuffers(1, &src_rb->Name);
-   _mesa_DeleteRenderbuffers(1, &dst_rb->Name);
+   _mesa_reference_renderbuffer(&src_rb, NULL);
+   _mesa_reference_renderbuffer(&dst_rb, NULL);
    _mesa_DeleteFramebuffers(2, fbos);
 
    _mesa_meta_end(ctx);