From 4a59ed8a077e0a4a6f52084c80c716b9936198ef Mon Sep 17 00:00:00 2001

From: Tyrel Datwyler <tyreld@linux.ibm.com>

Date: Thu, 11 Feb 2021 12:57:39 -0600

Subject: [PATCH 1/4] ibmvfc: simplify handling of sub-CRQ initialization

References: bsc#1182632 ltc#191222

Patch-mainline: submitted https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=229197

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.vnet.ibm.com>

Acked-by: Michal Suchanek <msuchanek@suse.de>

---

 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 a72ad6d12579..7be437e9d805 100644

--- a/drivers/scsi/ibmvscsi/ibmvfc.c

+++ b/drivers/scsi/ibmvscsi/ibmvfc.c

@@ -5707,17 +5707,21 @@ 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)) {

@@ -5726,13 +5730,12 @@ 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)

@@ -5999,11 +6002,7 @@ 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);

-- 

2.26.2