diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 02daf4e5c8e62bea56e7f2b036f89048679dc39f..1bd37e34c77ee1e7f1bd9734a95dd452985d911b 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1195,13 +1195,17 @@ static bool i915_switcheroo_can_switch(struct pci_dev *pdev)
 	return can_switch;
 }
 
-static int i915_load_modeset_init(struct drm_device *dev,
-				  unsigned long prealloc_size,
-				  unsigned long agp_size)
+static int i915_load_modeset_init(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	unsigned long prealloc_size, gtt_size, mappable_size;
 	int ret = 0;
 
+	prealloc_size = dev_priv->mm.gtt->gtt_stolen_entries << PAGE_SHIFT;
+	gtt_size = dev_priv->mm.gtt->gtt_total_entries << PAGE_SHIFT;
+	mappable_size = dev_priv->mm.gtt->gtt_mappable_entries << PAGE_SHIFT;
+	gtt_size -= PAGE_SIZE;
+
 	/* Basic memrange allocator for stolen space (aka mm.vram) */
 	drm_mm_init(&dev_priv->mm.vram, 0, prealloc_size);
 
@@ -1214,7 +1218,7 @@ static int i915_load_modeset_init(struct drm_device *dev,
 	 * at the last page of the aperture.  One page should be enough to
 	 * keep any prefetching inside of the aperture.
 	 */
-	i915_gem_do_init(dev, prealloc_size, agp_size - 4096);
+	i915_gem_do_init(dev, prealloc_size, mappable_size, gtt_size);
 
 	mutex_lock(&dev->struct_mutex);
 	ret = i915_gem_init_ringbuffer(dev);
@@ -2056,7 +2060,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 	intel_detect_pch(dev);
 
 	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
-		ret = i915_load_modeset_init(dev, prealloc_size, agp_size);
+		ret = i915_load_modeset_init(dev);
 		if (ret < 0) {
 			DRM_ERROR("failed to init modeset\n");
 			goto out_workqueue_free;
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 263bb050624768d3f0c36781069099793694b74c..296ed38b292f34d6313f9768087e6fdcc149e6b7 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1041,7 +1041,7 @@ int i915_gem_object_set_domain(struct drm_gem_object *obj,
 int i915_gem_init_ringbuffer(struct drm_device *dev);
 void i915_gem_cleanup_ringbuffer(struct drm_device *dev);
 int i915_gem_do_init(struct drm_device *dev, unsigned long start,
-		     unsigned long end);
+		     unsigned long mappable_end, unsigned long end);
 int i915_gpu_idle(struct drm_device *dev);
 int i915_gem_idle(struct drm_device *dev);
 int i915_add_request(struct drm_device *dev,
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 7b06807141012aaaf46b54d76e466a3d9ed8688f..6d9971f0ed928f6742b68909975543b8ec0c0c4b 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -173,6 +173,7 @@ i915_gem_object_is_inactive(struct drm_i915_gem_object *obj_priv)
 
 int i915_gem_do_init(struct drm_device *dev,
 		     unsigned long start,
+		     unsigned long mappable_end,
 		     unsigned long end)
 {
 	drm_i915_private_t *dev_priv = dev->dev_private;
@@ -187,7 +188,7 @@ int i915_gem_do_init(struct drm_device *dev,
 		    end - start);
 
 	dev_priv->mm.gtt_total = end - start;
-	dev_priv->mm.gtt_mappable_end = end;
+	dev_priv->mm.gtt_mappable_end = mappable_end;
 
 	return 0;
 }
@@ -200,7 +201,7 @@ i915_gem_init_ioctl(struct drm_device *dev, void *data,
 	int ret;
 
 	mutex_lock(&dev->struct_mutex);
-	ret = i915_gem_do_init(dev, args->gtt_start, args->gtt_end);
+	ret = i915_gem_do_init(dev, args->gtt_start, args->gtt_end, args->gtt_end);
 	mutex_unlock(&dev->struct_mutex);
 
 	return ret;