+ /*
+ * The goal is to evict objects and amalgamate space in LRU order.
+ * The oldest idle objects reside on the inactive list, which is in
+ * retirement order. The next objects to retire are those on the (per
+ * ring) active list that do not have an outstanding flush. Once the
+ * hardware reports completion (the seqno is updated after the
+ * batchbuffer has been finished) the clean buffer objects would
+ * be retired to the inactive list. Any dirty objects would be added
+ * to the tail of the flushing list. So after processing the clean
+ * active objects we need to emit a MI_FLUSH to retire the flushing
+ * list, hence the retirement order of the flushing list is in
+ * advance of the dirty objects on the active lists.
+ *
+ * The retirement sequence is thus:
+ * 1. Inactive objects (already retired)
+ * 2. Clean active objects
+ * 3. Flushing list
+ * 4. Dirty active objects.
+ *
+ * On each list, the oldest objects lie at the HEAD with the freshest
+ * object on the TAIL.
+ */
+
+ INIT_LIST_HEAD(&unwind_list);
+ drm_mm_init_scan(&dev_priv->mm.gtt_space, min_size, alignment);
+
+ /* First see if there is a large enough contiguous idle region... */
+ list_for_each_entry(obj_priv, &dev_priv->mm.inactive_list, list) {
+ if (mark_free(obj_priv, &unwind_list))
+ goto found;
+ }