scsi: always assign block layer tags if enabled

Allow a driver to ask for block layer tags by setting .use_blk_tags in the
host template, in which case it will always see a valid value in
request->tag, similar to the behavior when using blk-mq.  This means even
SCSI "untagged" commands will now have a tag, which is especially useful
when using a host-wide tag map.

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

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c
index e30932f989a1..120a851df0d7 100644
--- a/drivers/target/loopback/tcm_loop.c
+++ b/drivers/target/loopback/tcm_loop.c
@@ -407,7 +407,6 @@ static int tcm_loop_slave_alloc(struct scsi_device *sd)
 static int tcm_loop_slave_configure(struct scsi_device *sd)
 {
         if (sd->tagged_supported) {
-                scsi_activate_tcq(sd, sd->queue_depth);
                 scsi_adjust_queue_depth(sd, MSG_SIMPLE_TAG,
                                         sd->host->cmd_per_lun);
         } else {
@@ -437,6 +436,7 @@ static struct scsi_host_template tcm_loop_driver_template = {
         .slave_alloc            = tcm_loop_slave_alloc,
         .slave_configure        = tcm_loop_slave_configure,
         .module                 = THIS_MODULE,
+        .use_blk_tags           = 1,
 };
 
 static int tcm_loop_driver_probe(struct device *dev)