scsi: don't set tagging state from scsi_adjust_queue_depth

Remove the tagged argument from scsi_adjust_queue_depth, and just let it
handle the queue depth.  For most drivers those two are fairly separate,
given that most modern drivers don't care about the SCSI "tagged" status
of a command at all, and many old drivers allow queuing of multiple
untagged commands in the driver.

Instead we start out with the ->simple_tags flag set before calling
->slave_configure, which is how all drivers actually looking at
->simple_tags except for one worke anyway.  The one other case looks
broken, but I've kept the behavior as-is for now.

Except for that we only change ->simple_tags from the ->change_queue_type,
and when rejecting a tag message in a single driver, so keeping this
churn out of scsi_adjust_queue_depth is a clear win.

Now that the usage of scsi_adjust_queue_depth is more obvious we can
also remove all the trivial instances in ->slave_alloc or ->slave_configure
that just set it to the cmd_per_lun default.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 2 insertions, 6 deletions

diff --git a/drivers/scsi/aic7xxx/aic7xxx_osm.c b/drivers/scsi/aic7xxx/aic7xxx_osm.c
index f18b6d69d3fb..a6a27d5398dd 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_osm.c
+++ b/drivers/scsi/aic7xxx/aic7xxx_osm.c
@@ -1335,13 +1335,9 @@ ahc_platform_set_tags(struct ahc_softc *ahc, struct scsi_device *sdev,
 	}
 	switch ((dev->flags & (AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED))) {
 	case AHC_DEV_Q_BASIC:
-		scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TASK,
-				dev->openings + dev->active);
-		break;
 	case AHC_DEV_Q_TAGGED:
-		scsi_adjust_queue_depth(sdev, MSG_ORDERED_TASK,
+		scsi_adjust_queue_depth(sdev,
 				dev->openings + dev->active);
-		break;
 	default:
 		/*
 		 * We allow the OS to queue 2 untagged transactions to
@@ -1349,7 +1345,7 @@ ahc_platform_set_tags(struct ahc_softc *ahc, struct scsi_device *sdev,
 		 * serially on the controller/device.  This should
 		 * remove some latency.
 		 */
-		scsi_adjust_queue_depth(sdev, 0, 2);
+		scsi_adjust_queue_depth(sdev, 2);
 		break;
 	}
 }