drm: pre allocate node for create_block

For an upcoming patch where we introduce the i915 VMA, it's ideal to
have the drm_mm_node as part of the VMA struct (ie. it's pre-allocated).
Part of the conversion to VMAs is to kill off obj->gtt_space. Doing this
will break a bunch of code, but amongst them are 2 callers of
drm_mm_create_block(), both related to stolen memory.

It also allows us to embed the drm_mm_node into the object currently
which provides a nice transition over to the new code.

v2: Reordered to do before ripping out obj->gtt_offset.
Some minor cleanups made available because of reordering.

v3: s/continue/break on failed stolen node allocation (David)
Set obj->gtt_space on failed node allocation (David)
Only unref stolen (fix double free) on failed create_stolen (David)
Free node, and NULL it in failed create_stolen (David)
Add back accidentally removed newline (David)

CC: <dri-devel@lists.freedesktop.org>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Acked-by: David Airlie <airlied@linux.ie>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 16 insertions, 4 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 66929eac636..88180a597c0 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -629,14 +629,26 @@ void i915_gem_setup_global_gtt(struct drm_device *dev,
 
 	/* Mark any preallocated objects as occupied */
 	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
+		int ret;
 		DRM_DEBUG_KMS("reserving preallocated space: %x + %zx\n",
 			      obj->gtt_offset, obj->base.size);
 
 		BUG_ON(obj->gtt_space != I915_GTT_RESERVED);
-		obj->gtt_space = drm_mm_create_block(&dev_priv->mm.gtt_space,
-						     obj->gtt_offset,
-						     obj->base.size,
-						     false);
+		obj->gtt_space = kzalloc(sizeof(*obj->gtt_space), GFP_KERNEL);
+		if (!obj->gtt_space) {
+			DRM_ERROR("Failed to preserve object at offset %x\n",
+				  obj->gtt_offset);
+			continue;
+		}
+		ret = drm_mm_create_block(&dev_priv->mm.gtt_space,
+					  obj->gtt_space,
+					  obj->gtt_offset,
+					  obj->base.size);
+		if (ret) {
+			DRM_DEBUG_KMS("Reservation failed\n");
+			kfree(obj->gtt_space);
+			obj->gtt_space = NULL;
+		}
 		obj->has_global_gtt_mapping = 1;
 	}