From: Jack Morgenstein <jackm@dev.mellanox.co.il>
Date: Wed, 28 Nov 2007 10:44:20 +0000 (+0200)
Subject: max_recv_wr must be > 0 for non-SRQ QPs
X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=af257cd5a6a2ff7c041fccff60fd714e2d2d93a0;p=~shefty%2Flibmlx4.git

max_recv_wr must be > 0 for non-SRQ QPs

max_recv_wr must also be non-zero for QPs which are not associated
with an SRQ.

Without this patch, if the userspace caller specifies max_recv_wr == 0
for a non-srq QP, the creation will be rejected in kernel space in
file infiniband/hw/mlx4/qp.c, function set_rq_size():

	} else {
		/* HW requires >= 1 RQ entry with >= 1 gather entry */
==> NOTE:	if (is_user && (!cap->max_recv_wr || !cap->max_recv_sge))
			return -EINVAL;

We make sure max_recv_sge is at least 1, but not max_recv_wr.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
---

diff --git a/src/verbs.c b/src/verbs.c
index 7fa1dbc..50e0947 100644
--- a/src/verbs.c
+++ b/src/verbs.c
@@ -367,8 +367,12 @@ struct ibv_qp *mlx4_create_qp(struct ibv_pd *pd, struct ibv_qp_init_attr *attr)
 
 	if (attr->srq)
 		attr->cap.max_recv_wr = qp->rq.wqe_cnt = 0;
-	else if (attr->cap.max_recv_sge < 1)
-		attr->cap.max_recv_sge = 1;
+	else {
+		if (attr->cap.max_recv_sge < 1)
+			attr->cap.max_recv_sge = 1;
+		if (attr->cap.max_recv_wr < 1)
+			attr->cap.max_recv_wr = 1;
+	}
 
 	if (mlx4_alloc_qp_buf(pd, &attr->cap, attr->qp_type, qp))
 		goto err;