[Mesa-dev] [PATCH 16/16] meta: Don't pollute the texture namespace

[Tapani Pälli]

series is
Reviewed-by: Tapani Pälli <tapani.palli at intel.com>

On 19.12.2017 02:14, Ian Romanick wrote:
> From: Ian Romanick <ian.d.romanick at intel.com>
> 
> 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 at intel.com>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92363
> ---
>   src/mesa/drivers/common/meta.c      | 21 ++++++---------------
>   src/mesa/drivers/common/meta_blit.c | 18 ++++--------------
>   2 files changed, 10 insertions(+), 29 deletions(-)
> 
> diff --git a/src/mesa/drivers/common/meta.c b/src/mesa/drivers/common/meta.c
> index 55d803f..f4830ec 100644
> --- a/src/mesa/drivers/common/meta.c
> +++ b/src/mesa/drivers/common/meta.c
> @@ -98,7 +98,8 @@ meta_clear(struct gl_context *ctx, GLbitfield buffers, bool glsl);
>   static struct blit_shader *
>   choose_blit_shader(GLenum target, struct blit_shader_table *table);
>   
> -static void cleanup_temp_texture(struct temp_texture *tex);
> +static void cleanup_temp_texture(struct gl_context *ctx,
> +                                 struct temp_texture *tex);
>   static void meta_glsl_clear_cleanup(struct gl_context *ctx,
>                                       struct clear_state *clear);
>   static void meta_decompress_cleanup(struct gl_context *ctx,
> @@ -418,7 +419,7 @@ _mesa_meta_free(struct gl_context *ctx)
>      _mesa_meta_glsl_blit_cleanup(ctx, &ctx->Meta->Blit);
>      meta_glsl_clear_cleanup(ctx, &ctx->Meta->Clear);
>      _mesa_meta_glsl_generate_mipmap_cleanup(ctx, &ctx->Meta->Mipmap);
> -   cleanup_temp_texture(&ctx->Meta->TempTex);
> +   cleanup_temp_texture(ctx, &ctx->Meta->TempTex);
>      meta_decompress_cleanup(ctx, &ctx->Meta->Decompress);
>      meta_drawpix_cleanup(ctx, &ctx->Meta->DrawPix);
>      if (old_context)
> @@ -1228,8 +1229,6 @@ invert_z(GLfloat normZ)
>   static void
>   init_temp_texture(struct gl_context *ctx, struct temp_texture *tex)
>   {
> -   GLuint texObj;
> -
>      /* prefer texture rectangle */
>      if (_mesa_is_desktop_gl(ctx) && ctx->Extensions.NV_texture_rectangle) {
>         tex->Target = GL_TEXTURE_RECTANGLE;
> @@ -1245,21 +1244,13 @@ init_temp_texture(struct gl_context *ctx, struct temp_texture *tex)
>      tex->MinSize = 16;  /* 16 x 16 at least */
>      assert(tex->MaxSize > 0);
>   
> -   _mesa_CreateTextures(tex->Target, 1, &texObj);
> -   tex->tex_obj = NULL;
> -
> -   if (texObj == 0)
> -      return;
> -
> -   tex->tex_obj = _mesa_lookup_texture(ctx, texObj);
> +   tex->tex_obj = ctx->Driver.NewTextureObject(ctx, 0xDEADBEEF, tex->Target);
>   }
>   
>   static void
> -cleanup_temp_texture(struct temp_texture *tex)
> +cleanup_temp_texture(struct gl_context *ctx, struct temp_texture *tex)
>   {
> -   if (tex->tex_obj == NULL)
> -     return;
> -   _mesa_DeleteTextures(1, &tex->tex_obj->Name);
> +   _mesa_delete_nameless_texture(ctx, tex->tex_obj);
>      tex->tex_obj = NULL;
>   }
>   
> diff --git a/src/mesa/drivers/common/meta_blit.c b/src/mesa/drivers/common/meta_blit.c
> index 95dfa64..496ef28 100644
> --- a/src/mesa/drivers/common/meta_blit.c
> +++ b/src/mesa/drivers/common/meta_blit.c
> @@ -879,9 +879,7 @@ _mesa_meta_fb_tex_blit_end(struct gl_context *ctx, GLenum target,
>      _mesa_bind_sampler(ctx, ctx->Texture.CurrentUnit, blit->samp_obj_save);
>      _mesa_reference_sampler_object(ctx, &blit->samp_obj_save, NULL);
>      _mesa_reference_sampler_object(ctx, &blit->samp_obj, NULL);
> -
> -   if (blit->temp_tex_obj)
> -      _mesa_DeleteTextures(1, &blit->temp_tex_obj->Name);
> +   _mesa_delete_nameless_texture(ctx, blit->temp_tex_obj);
>   }
>   
>   struct gl_texture_object *
> @@ -890,20 +888,14 @@ _mesa_meta_texture_object_from_renderbuffer(struct gl_context *ctx,
>   {
>      struct gl_texture_image *texImage;
>      struct gl_texture_object *texObj;
> -   GLuint tempTex;
>      const GLenum target = rb->NumSamples > 1
>         ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D;
>   
> -   tempTex = 0;
> -   _mesa_CreateTextures(target, 1, &tempTex);
> -   if (tempTex == 0)
> -      return NULL;
> -
> -   texObj = _mesa_lookup_texture(ctx, tempTex);
> +   texObj = ctx->Driver.NewTextureObject(ctx, 0xDEADBEEF, target);
>      texImage = _mesa_get_tex_image(ctx, texObj, target, 0);
>   
>      if (!ctx->Driver.BindRenderbufferTexImage(ctx, rb, texImage)) {
> -      _mesa_DeleteTextures(1, &tempTex);
> +      _mesa_delete_nameless_texture(ctx, texObj);
>         return NULL;
>      }
>   
> @@ -912,8 +904,6 @@ _mesa_meta_texture_object_from_renderbuffer(struct gl_context *ctx,
>         ctx->Driver.FinishRenderTexture(ctx, rb);
>      }
>   
> -   assert(target == texObj->Target);
> -   assert(tempTex == texObj->Name);
>      return texObj;
>   }
>   
> @@ -1057,7 +1047,7 @@ _mesa_meta_glsl_blit_cleanup(struct gl_context *ctx, struct blit_state *blit)
>      _mesa_meta_blit_shader_table_cleanup(ctx, &blit->shaders_without_depth);
>   
>      if (blit->depthTex.tex_obj != NULL) {
> -      _mesa_DeleteTextures(1, &blit->depthTex.tex_obj->Name);
> +      _mesa_delete_nameless_texture(ctx, blit->depthTex.tex_obj);
>         blit->depthTex.tex_obj = NULL;
>      }
>   }
>