+ return -EAGAIN;
+ }
+
+ /*
+ * read pair of barrier in blk_freeze_queue_start(), we need to
+ * order reading __PERCPU_REF_DEAD flag of .q_usage_counter and
+ * reading .mq_freeze_depth or queue dying flag, otherwise the
+ * following wait may never return if the two reads are
+ * reordered.
+ */
+ smp_rmb();
+ wait_event(q->mq_freeze_wq,
+ (!q->mq_freeze_depth &&
+ blk_pm_resume_queue(false, q)) ||
+ test_bit(GD_DEAD, &disk->state));
+ if (test_bit(GD_DEAD, &disk->state))
+ goto dead;