From: Lijun Ou <oulijun@huawei.com>
Date: Sat, 12 Jan 2019 18:36:29 +0800
Subject: RDMA/hns: RDMA/hns: Assign rq head pointer when enable rq record db
Patch-mainline: v5.1-rc1
Git-commit: de77503a59403e7045c18c6bb0a10c245a99b648
References: bsc#1104427 FATE#326416 bsc#1137236

When flush cqe, it needs to get the pointer of rq and sq from db address
space of user and update it into qp context by modified qp. if rq does not
exist, it will not get the value from db address space of user.

Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/hw/hns/hns_roce_qp.c |   19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

--- a/drivers/infiniband/hw/hns/hns_roce_qp.c
+++ b/drivers/infiniband/hw/hns/hns_roce_qp.c
@@ -676,6 +676,10 @@ static int hns_roce_create_qp_common(str
 				dev_err(dev, "rq record doorbell map failed!\n");
 				goto err_sq_dbmap;
 			}
+
+			/* indicate kernel supports rq record db */
+			resp.cap_flags |= HNS_ROCE_SUPPORT_RQ_RECORD_DB;
+			hr_qp->rdb_en = 1;
 		}
 	} else {
 		if (init_attr->create_flags &
@@ -784,16 +788,11 @@ static int hns_roce_create_qp_common(str
 	else
 		hr_qp->doorbell_qpn = cpu_to_le64(hr_qp->qpn);
 
-	if (ib_pd->uobject && (udata->outlen >= sizeof(resp)) &&
-		(hr_dev->caps.flags & HNS_ROCE_CAP_FLAG_RECORD_DB)) {
-
-		/* indicate kernel supports rq record db */
-		resp.cap_flags |= HNS_ROCE_SUPPORT_RQ_RECORD_DB;
-		ret = ib_copy_to_udata(udata, &resp, sizeof(resp));
+	if (udata) {
+		ret = ib_copy_to_udata(udata, &resp,
+				       min(udata->outlen, sizeof(resp)));
 		if (ret)
 			goto err_qp;
-
-		hr_qp->rdb_en = 1;
 	}
 	hr_qp->event = hns_roce_ib_qp_event;
 
@@ -970,7 +969,9 @@ int hns_roce_modify_qp(struct ib_qp *ibq
 	    (attr_mask & IB_QP_STATE) && new_state == IB_QPS_ERR) {
 		if (hr_qp->sdb_en == 1) {
 			hr_qp->sq.head = *(int *)(hr_qp->sdb.virt_addr);
-			hr_qp->rq.head = *(int *)(hr_qp->rdb.virt_addr);
+
+			if (hr_qp->rdb_en == 1)
+				hr_qp->rq.head = *(int *)(hr_qp->rdb.virt_addr);
 		} else {
 			dev_warn(dev, "flush cqe is not supported in userspace!\n");
 			goto out;