scsi: use host wide tags by default

This patch changes the !blk-mq path to the same defaults as the blk-mq
I/O path by always enabling block tagging, and always using host wide
tags.  We've had blk-mq available for a few releases so bugs with
this mode should have been ironed out, and this ensures we get better
coverage of over tagging setup over different configs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index 8bb173e..323982f 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -217,6 +217,13 @@
 		error = scsi_mq_setup_tags(shost);
 		if (error)
 			goto fail;
+	} else {
+		shost->bqt = blk_init_tags(shost->can_queue,
+				shost->hostt->tag_alloc_policy);
+		if (!shost->bqt) {
+			error = -ENOMEM;
+			goto fail;
+		}
 	}
 
 	/*