spin_unlock_irqrestore(&fq->mq_flush_lock, flags);
}
+bool is_flush_rq(struct request *rq)
+{
+ return rq->end_io == flush_end_io;
+}
+
/**
* blk_kick_flush - consider issuing flush request
* @q: request_queue being kicked
flush_rq->rq_flags |= RQF_FLUSH_SEQ;
flush_rq->rq_disk = first_rq->rq_disk;
flush_rq->end_io = flush_end_io;
+ /*
+ * Order WRITE ->end_io and WRITE rq->ref, and its pair is the one
+ * implied in refcount_inc_not_zero() called from
+ * blk_mq_find_and_get_req(), which orders WRITE/READ flush_rq->ref
+ * and READ flush_rq->end_io
+ */
+ smp_wmb();
+ refcount_set(&flush_rq->ref, 1);
blk_flush_queue_rq(flush_rq, false);
}