}
blk_rq_init(q, rq);
+ rq->cmd_type = REQ_TYPE_FS;
rq->cmd_flags = REQ_HARDBARRIER | REQ_FLUSH;
- rq->rq_disk = q->bar_rq.rq_disk;
+ rq->rq_disk = q->orig_bar_rq->rq_disk;
rq->end_io = end_io;
elv_insert(q, rq, ELEVATOR_INSERT_FRONT);
if (!q)
return -ENXIO;
+ /*
+ * some block devices may not have their queue correctly set up here
+ * (e.g. loop device without a backing file) and so issuing a flush
+ * here will panic. Ensure there is a request function before issuing
+ * the barrier.
+ */
+ if (!q->make_request_fn)
+ return -ENXIO;
+
bio = bio_alloc(gfp_mask, 0);
bio->bi_end_io = bio_end_empty_barrier;
bio->bi_bdev = bdev;