From: Bart Van Assche <bvanassche@acm.org>
Date: Mon, 25 May 2020 10:22:12 -0700
Subject: RDMA/srpt: Increase max_send_sge
Patch-mainline: v5.8-rc1
Git-commit: e0cca8b456e2319804c9187f237268b14c50d323
References: jsc#SLE-15176

The ib_srpt driver limits max_send_sge to 16. Since that is a workaround
for an mlx4 bug that has been fixed, increase max_send_sge. See also
commit f95ccffc715b ("IB/mlx4: Use 4K pages for kernel QP's WQE buffer").

Link: https://lore.kernel.org/r/20200525172212.14413-5-bvanassche@acm.org
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/ulp/srpt/ib_srpt.c |    3 +--
 drivers/infiniband/ulp/srpt/ib_srpt.h |    5 -----
 2 files changed, 1 insertion(+), 7 deletions(-)

--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -1816,8 +1816,7 @@ retry:
 	 */
 	qp_init->cap.max_send_wr = min(sq_size / 2, attrs->max_qp_wr);
 	qp_init->cap.max_rdma_ctxs = sq_size / 2;
-	qp_init->cap.max_send_sge = min(attrs->max_send_sge,
-					SRPT_MAX_SG_PER_WQE);
+	qp_init->cap.max_send_sge = attrs->max_send_sge;
 	qp_init->cap.max_recv_sge = 1;
 	qp_init->port_num = ch->sport->port;
 	if (sdev->use_srq)
--- a/drivers/infiniband/ulp/srpt/ib_srpt.h
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.h
@@ -105,11 +105,6 @@ enum {
 	SRP_CMD_ACA = 0x4,
 
 	SRPT_DEF_SG_TABLESIZE = 128,
-	/*
-	 * An experimentally determined value that avoids that QP creation
-	 * fails due to "swiotlb buffer is full" on systems using the swiotlb.
-	 */
-	SRPT_MAX_SG_PER_WQE = 16,
 
 	MIN_SRPT_SQ_SIZE = 16,
 	DEF_SRPT_SQ_SIZE = 4096,