[PATCH v4 1/5] ibmvfc: simplify handling of sub-CRQ initialization

From: Tyrel Datwyler <tyreld@linux.ibm.com>
To: james.bottomley@hansenpartnership.com
Cc: martin.petersen@oracle.com, linux-scsi@vger.kernel.org,
	linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
	brking@linux.ibm.com, Tyrel Datwyler <tyreld@linux.ibm.com>
Subject: [PATCH v4 1/5] ibmvfc: simplify handling of sub-CRQ initialization
Date: Thu, 25 Feb 2021 15:50:53 -0600	[thread overview]
Message-ID: <20210225215057.23020-2-tyreld@linux.ibm.com> (raw)
In-Reply-To: <20210225215057.23020-1-tyreld@linux.ibm.com>

If ibmvfc_init_sub_crqs() fails ibmvfc_probe() simply parrots
registration failure reported elsewhere, and futher
vhost->scsi_scrq.scrq == NULL is indication enough to the driver that it
has no sub-CRQs available. The mq_enabled check can also be moved into
ibmvfc_init_sub_crqs() such that each caller doesn't have to gate the
call with a mq_enabled check. Finally, in the case of sub-CRQ setup
failure setting do_enquiry can be turned off to putting the driver into
single queue fallback mode.

The aforementioned changes also simplify the next patch in the series
that fixes a hard reset issue, by tying a sub-CRQ setup failure and
do_enquiry logic into ibmvfc_init_sub_crqs().

Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Reviewed-by: Brian King <brking@linux.ibm.com>
---
 drivers/scsi/ibmvscsi/ibmvfc.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index 7097028d4cb6..384960036f8b 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -5705,17 +5705,21 @@ static void ibmvfc_deregister_scsi_channel(struct ibmvfc_host *vhost, int index)
 	LEAVE;
 }
 
-static int ibmvfc_init_sub_crqs(struct ibmvfc_host *vhost)
+static void ibmvfc_init_sub_crqs(struct ibmvfc_host *vhost)
 {
 	int i, j;
 
 	ENTER;
+	if (!vhost->mq_enabled)
+		return;
 
 	vhost->scsi_scrqs.scrqs = kcalloc(nr_scsi_hw_queues,
 					  sizeof(*vhost->scsi_scrqs.scrqs),
 					  GFP_KERNEL);
-	if (!vhost->scsi_scrqs.scrqs)
-		return -1;
+	if (!vhost->scsi_scrqs.scrqs) {
+		vhost->do_enquiry = 0;
+		return;
+	}
 
 	for (i = 0; i < nr_scsi_hw_queues; i++) {
 		if (ibmvfc_register_scsi_channel(vhost, i)) {
@@ -5724,13 +5728,12 @@ static int ibmvfc_init_sub_crqs(struct ibmvfc_host *vhost)
 			kfree(vhost->scsi_scrqs.scrqs);
 			vhost->scsi_scrqs.scrqs = NULL;
 			vhost->scsi_scrqs.active_queues = 0;
-			LEAVE;
-			return -1;
+			vhost->do_enquiry = 0;
+			break;
 		}
 	}
 
 	LEAVE;
-	return 0;
 }
 
 static void ibmvfc_release_sub_crqs(struct ibmvfc_host *vhost)
@@ -5997,11 +6000,7 @@ static int ibmvfc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 		goto remove_shost;
 	}
 
-	if (vhost->mq_enabled) {
-		rc = ibmvfc_init_sub_crqs(vhost);
-		if (rc)
-			dev_warn(dev, "Failed to allocate Sub-CRQs. rc=%d\n", rc);
-	}
+	ibmvfc_init_sub_crqs(vhost);
 
 	if (shost_to_fc_host(shost)->rqst_q)
 		blk_queue_max_segments(shost_to_fc_host(shost)->rqst_q, 1);
-- 
2.27.0

