drm/i915: track objects in the gtt

This is required to restore gtt mappings on resume when agp is gone.

The right way to do this would be to make sturct drm_mm_node embeddable
and use the allocation list maintained by the drm memory manager. But
that's a bigger project. Getting rid of the per bo agp_mem will save
more memory than this wastes, anyway.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index b663d2d..07e1b25 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -95,6 +95,7 @@
 			min_t(size_t, obj->gtt_space->size,
 			      dev_priv->mm.gtt_mappable_end - obj->gtt_offset);
 	}
+	list_add_tail(&obj->gtt_list, &dev_priv->mm.gtt_list);
 }
 
 static void i915_gem_info_remove_gtt(struct drm_i915_private *dev_priv,
@@ -107,6 +108,7 @@
 			min_t(size_t, obj->gtt_space->size,
 			      dev_priv->mm.gtt_mappable_end - obj->gtt_offset);
 	}
+	list_del_init(&obj->gtt_list);
 }
 
 /**
@@ -4604,6 +4606,7 @@
 	obj->base.driver_private = NULL;
 	obj->fence_reg = I915_FENCE_REG_NONE;
 	INIT_LIST_HEAD(&obj->mm_list);
+	INIT_LIST_HEAD(&obj->gtt_list);
 	INIT_LIST_HEAD(&obj->ring_list);
 	INIT_LIST_HEAD(&obj->gpu_write_list);
 	obj->madv = I915_MADV_WILLNEED;
@@ -4916,6 +4919,7 @@
 	INIT_LIST_HEAD(&dev_priv->mm.pinned_list);
 	INIT_LIST_HEAD(&dev_priv->mm.fence_list);
 	INIT_LIST_HEAD(&dev_priv->mm.deferred_free_list);
+	INIT_LIST_HEAD(&dev_priv->mm.gtt_list);
 	init_ring_lists(&dev_priv->render_ring);
 	init_ring_lists(&dev_priv->bsd_ring);
 	init_ring_lists(&dev_priv->blt_ring);