drm/i915/gtt: Reorder aliasing_ppgtt fini

To allow ourselves to use a first class vma for the aliasing_ppgtt page
directory, we have to reorder the shutdown on module unload to remove
and unpin the aliasing_ppgtt before complaining about any objects left
in the GGTT.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180609090151.22007-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_gem_gtt.c

@@ -2870,15 +2870,11 @@ void i915_ggtt_cleanup_hw(struct drm_i915_private *dev_priv)
 	ggtt->vm.closed = true;
 
 	mutex_lock(&dev_priv->drm.struct_mutex);
+	i915_gem_fini_aliasing_ppgtt(dev_priv);
+
 	GEM_BUG_ON(!list_empty(&ggtt->vm.active_list));
 	list_for_each_entry_safe(vma, vn, &ggtt->vm.inactive_list, vm_link)
 		WARN_ON(i915_vma_unbind(vma));
-	mutex_unlock(&dev_priv->drm.struct_mutex);
-
-	i915_gem_cleanup_stolen(&dev_priv->drm);
-
-	mutex_lock(&dev_priv->drm.struct_mutex);
-	i915_gem_fini_aliasing_ppgtt(dev_priv);
 
 	if (drm_mm_node_allocated(&ggtt->error_capture))
 		drm_mm_remove_node(&ggtt->error_capture);
@@ -2900,6 +2896,8 @@ void i915_ggtt_cleanup_hw(struct drm_i915_private *dev_priv)
 
 	arch_phys_wc_del(ggtt->mtrr);
 	io_mapping_fini(&ggtt->iomap);
+
+	i915_gem_cleanup_stolen(&dev_priv->drm);
 }
 
 static unsigned int gen6_get_total_gtt_size(u16 snb_gmch_ctl)