st/mesa: Allow zero as [level|layer]_override

This fix two dEQP tests for virgl:

dEQP-EGL.functional.image.create.gles2_cubemap_positive_x_rgba_texture
dEQP-EGL.functional.image.render_multiple_contexts.gles2_cubemap_positive_x_rgba8_texture

Signed-off-by: Lepton Wu <lepton@chromium.org>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>

src/mesa/state_tracker/st_cb_texture.c

@@ -157,6 +157,9 @@ st_NewTextureObject(struct gl_context * ctx, GLuint name, GLenum target)
    if (!obj)
       return NULL;
 
+   obj->level_override = -1;
+   obj->layer_override = -1;
+
    /* Pre-allocate a sampler views container to save a branch in the
     * fast path.
     */
@@ -754,8 +757,8 @@ prep_teximage(struct gl_context *ctx, struct gl_texture_image *texImage,
 
       assert(!st_texture_image(texImage)->pt);
       _mesa_clear_texture_object(ctx, texObj, texImage);
-      stObj->layer_override = 0;
-      stObj->level_override = 0;
+      stObj->layer_override = -1;
+      stObj->level_override = -1;
       pipe_resource_reference(&stObj->pt, NULL);
 
       /* oops, need to init this image again */

src/mesa/state_tracker/st_sampler_view.c

@@ -527,13 +527,13 @@ st_create_texture_sampler_view_from_stobj(struct st_context *st,
 
    templ.format = format;
 
-   if (stObj->level_override) {
+   if (stObj->level_override >= 0) {
       templ.u.tex.first_level = templ.u.tex.last_level = stObj->level_override;
    } else {
       templ.u.tex.first_level = stObj->base.MinLevel + stObj->base.BaseLevel;
       templ.u.tex.last_level = last_level(stObj);
    }
-   if (stObj->layer_override) {
+   if (stObj->layer_override >= 0) {
       templ.u.tex.first_layer = templ.u.tex.last_layer = stObj->layer_override;
    } else {
       templ.u.tex.first_layer = stObj->base.MinLayer;
@@ -578,12 +578,12 @@ st_get_texture_sampler_view_from_stobj(struct st_context *st,
       assert(!check_sampler_swizzle(st, stObj, view, glsl130_or_later));
       assert(get_sampler_view_format(st, stObj, srgb_skip_decode) == view->format);
       assert(gl_target_to_pipe(stObj->base.Target) == view->target);
-      assert(stObj->level_override ||
+      assert(stObj->level_override >= 0 ||
              stObj->base.MinLevel + stObj->base.BaseLevel == view->u.tex.first_level);
-      assert(stObj->level_override || last_level(stObj) == view->u.tex.last_level);
-      assert(stObj->layer_override || stObj->base.MinLayer == view->u.tex.first_layer);
-      assert(stObj->layer_override || last_layer(stObj) == view->u.tex.last_layer);
-      assert(!stObj->layer_override ||
+      assert(stObj->level_override >= 0 || last_level(stObj) == view->u.tex.last_level);
+      assert(stObj->layer_override >= 0 || stObj->base.MinLayer == view->u.tex.first_layer);
+      assert(stObj->layer_override >= 0 || last_layer(stObj) == view->u.tex.last_layer);
+      assert(stObj->layer_override < 0 ||
              (stObj->layer_override == view->u.tex.first_layer &&
               stObj->layer_override == view->u.tex.last_layer));
       return view;

src/mesa/state_tracker/st_texture.h

@@ -164,15 +164,15 @@ struct st_texture_object
     */
    enum pipe_format surface_format;
 
-   /* When non-zero, samplers should use this level instead of the level
+   /* When non-negative, samplers should use this level instead of the level
     * range specified by the GL state.
     *
     * This is used for EGL images, which may correspond to a single level out
     * of an imported pipe_resources with multiple mip levels.
     */
-   uint level_override;
+   int level_override;
 
-   /* When non-zero, samplers should use this layer instead of the one
+   /* When non-negative, samplers should use this layer instead of the one
     * specified by the GL state.
     *
     * This is used for EGL images and VDPAU interop, where imported
@@ -180,7 +180,7 @@ struct st_texture_object
     * with different fields in the case of VDPAU) even though the GL state
     * describes one non-array texture per field.
     */
-   uint layer_override;
+   int layer_override;
 
     /**
      * Set when the texture images of this texture object might not all be in

src/mesa/state_tracker/st_vdpau.c

@@ -191,7 +191,7 @@ st_vdpau_map_surface(struct gl_context *ctx, GLenum target, GLenum access,
 
    struct pipe_resource *res;
    mesa_format texFormat;
-   uint layer_override = 0;
+   int layer_override = -1;
 
    if (output) {
       res = st_vdpau_output_surface_dma_buf(ctx, vdpSurface);
@@ -248,7 +248,7 @@ st_vdpau_map_surface(struct gl_context *ctx, GLenum target, GLenum access,
    pipe_resource_reference(&stImage->pt, res);
 
    stObj->surface_format = res->format;
-   stObj->level_override = 0;
+   stObj->level_override = -1;
    stObj->layer_override = layer_override;
 
    _mesa_dirty_texobj(ctx, texObj);
@@ -269,8 +269,8 @@ st_vdpau_unmap_surface(struct gl_context *ctx, GLenum target, GLenum access,
    st_texture_release_all_sampler_views(st, stObj);
    pipe_resource_reference(&stImage->pt, NULL);
 
-   stObj->level_override = 0;
-   stObj->layer_override = 0;
+   stObj->level_override = -1;
+   stObj->layer_override = -1;
 
    _mesa_dirty_texobj(ctx, texObj);