drm/i915: Handle inactivating objects for all VMAs

This came from a patch called, "drm/i915: Move active to vma"

When moving an object to the inactive list, we do it for all VMs for
which the object is bound.

The primary difference from that patch is this time around we don't not
track 'active' per vma, but rather by object. Therefore, we only need
one unref.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_gem.c

@@ -2008,13 +2008,17 @@ static void
 i915_gem_object_move_to_inactive(struct drm_i915_gem_object *obj)
 {
 	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
-	struct i915_address_space *ggtt_vm = &dev_priv->gtt.base;
-	struct i915_vma *vma = i915_gem_obj_to_vma(obj, ggtt_vm);
+	struct i915_address_space *vm;
+	struct i915_vma *vma;
 
 	BUG_ON(obj->base.write_domain & ~I915_GEM_GPU_DOMAINS);
 	BUG_ON(!obj->active);
 
-	list_move_tail(&vma->mm_list, &ggtt_vm->inactive_list);
+	list_for_each_entry(vm, &dev_priv->vm_list, global_link) {
+		vma = i915_gem_obj_to_vma(obj, vm);
+		if (vma && !list_empty(&vma->mm_list))
+			list_move_tail(&vma->mm_list, &vm->inactive_list);
+	}
 
 	list_del_init(&obj->ring_list);
 	obj->ring = NULL;