[mutter] renderer-native: Remove no_add_fb2

[Jonas Ådahl <jadahl src gnome org>]

commit f2dea5d1395093186165a4600838b195d873fada
Author: Daniel Stone <daniels collabora com>
Date:   Tue Jan 9 15:50:37 2018 +0000

    renderer-native: Remove no_add_fb2
    
    drmModeAddFB2 allows userspace to specify a real format enum on
    non-ancient kernels, as an improvement over the legacy drmModeAddFB
    which derives format from a fixed depth/bpp mapping.
    
    As an optimisation, Weston used to decide at the first failure of
    drmModeAddFB2 that the ioctl was unavailable: as non-existent DRM
    ioctls return -EINVAL rather than -ENOSYS or similar, bad parameters are
    not distinguishable from the ioctl not being present.
    
    Mutter has also implemented the same optimisation for dumb framebuffers,
    which potentially papers over errors for the gain of avoiding one ioctl
    which will rapidly fail on ancient kernels. Remove the optimisation and
    always use AddFB2 where possible.
    
    Closes: #14

 src/backends/native/meta-renderer-native.c | 32 +++++++++++-------------------
 1 file changed, 12 insertions(+), 20 deletions(-)
---
diff --git a/src/backends/native/meta-renderer-native.c b/src/backends/native/meta-renderer-native.c
index 772ce07f1..c1a918efd 100644
--- a/src/backends/native/meta-renderer-native.c
+++ b/src/backends/native/meta-renderer-native.c
@@ -103,8 +103,6 @@ typedef struct _MetaRendererNativeGpuData
 
   MetaRendererNativeMode mode;
 
-  gboolean no_add_fb2;
-
   EGLDisplay egl_display;
 
   /*
@@ -2181,14 +2179,15 @@ init_dumb_fb (MetaDumbBuffer  *dumb_fb,
               uint32_t         format,
               GError         **error)
 {
-  MetaRendererNative *renderer_native = meta_renderer_native_from_gpu (gpu_kms);
-  MetaRendererNativeGpuData *renderer_gpu_data;
   struct drm_mode_create_dumb create_arg;
   struct drm_mode_destroy_dumb destroy_arg;
   struct drm_mode_map_dumb map_arg;
   uint32_t fb_id = 0;
   void *map;
   int kms_fd;
+  uint32_t handles[4] = { 0, };
+  uint32_t pitches[4] = { 0, };
+  uint32_t offsets[4] = { 0, };
 
   kms_fd = meta_gpu_kms_get_fd (gpu_kms);
 
@@ -2206,25 +2205,18 @@ init_dumb_fb (MetaDumbBuffer  *dumb_fb,
       goto err_ioctl;
     }
 
-  renderer_gpu_data = meta_renderer_native_get_gpu_data (renderer_native,
-                                                         gpu_kms);
-  if (!renderer_gpu_data->no_add_fb2)
-    {
-      uint32_t handles[4] = { create_arg.handle, };
-      uint32_t pitches[4] = { create_arg.pitch, };
-      uint32_t offsets[4] = { 0 };
+  handles[0] = create_arg.handle;
+  pitches[0] = create_arg.pitch;
 
-      if (drmModeAddFB2 (kms_fd, width, height, format,
-                         handles, pitches, offsets,
-                         &fb_id, 0) != 0)
-        {
-          g_warning ("drmModeAddFB2 failed (%s), falling back to drmModeAddFB",
-                     g_strerror (errno));
-          renderer_gpu_data->no_add_fb2 = TRUE;
-        }
+  if (drmModeAddFB2 (kms_fd, width, height, format,
+                     handles, pitches, offsets,
+                     &fb_id, 0) != 0)
+    {
+      g_debug ("drmModeAddFB2 failed (%s), falling back to drmModeAddFB",
+               g_strerror (errno));
     }
 
-  if (renderer_gpu_data->no_add_fb2)
+  if (fb_id == 0)
     {
       if (drmModeAddFB (kms_fd, width, height,
                         24 /* depth of RGBX8888 */,