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>
diff --git a/Documentation/scsi/scsi_mid_low_api.txt b/Documentation/scsi/scsi_mid_low_api.txt
index a671942..bee7d86 100644
--- a/Documentation/scsi/scsi_mid_low_api.txt
+++ b/Documentation/scsi/scsi_mid_low_api.txt
@@ -271,9 +271,9 @@
slave_destroy() ***
------------------------------------------------------------
-The mid level invokes scsi_adjust_queue_depth() with tagged queuing off and
-"cmd_per_lun" for that host as the queue length. These settings can be
-overridden by a slave_configure() supplied by the LLD.
+The mid level invokes scsi_adjust_queue_depth() with "cmd_per_lun" for that
+host as the queue length. These settings can be overridden by a
+slave_configure() supplied by the LLD.
*** For scsi devices that the mid level tries to scan but do not
respond, a slave_alloc(), slave_destroy() pair is called.
@@ -438,9 +438,6 @@
/**
* scsi_adjust_queue_depth - allow LLD to change queue depth on a SCSI device
* @sdev: pointer to SCSI device to change queue depth on
- * @tagged: 0 - no tagged queuing
- * MSG_SIMPLE_TAG - simple tagged queuing
- * MSG_ORDERED_TAG - ordered tagged queuing
* @tags Number of tags allowed if tagged queuing enabled,
* or number of commands the LLD can queue up
* in non-tagged mode (as per cmd_per_lun).
@@ -456,8 +453,7 @@
* Defined in: drivers/scsi/scsi.c [see source code for more notes]
*
**/
-void scsi_adjust_queue_depth(struct scsi_device * sdev, int tagged,
- int tags)
+void scsi_adjust_queue_depth(struct scsi_device *sdev, int tags)
/**
