From: Bart Van Assche <bvanassche@acm.org>
Date: Mon, 30 Sep 2019 16:16:59 -0700
Subject: RDMA/srp: Honor the max_send_sge device attribute
Patch-mainline: v5.5-rc1
Git-commit: bf583470617e31c836afc4fa2039dabc43350533
References: jsc#SLE-8449
Instead of assuming that max_send_sge >= 3, restrict the number of scatter
gather elements to what is supported by the RDMA adapter.
Link: https://lore.kernel.org/r/20190930231707.48259-8-bvanassche@acm.org
Cc: Honggang LI <honli@redhat.com>
Cc: Laurence Oberman <loberman@redhat.com>
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/srp/ib_srp.c | 7 +++++--
drivers/infiniband/ulp/srp/ib_srp.h | 1 +
2 files changed, 6 insertions(+), 2 deletions(-)
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -552,6 +552,7 @@ static int srp_create_ch_ib(struct srp_r
{
struct srp_target_port *target = ch->target;
struct srp_device *dev = target->srp_host->srp_dev;
+ const struct ib_device_attr *attr = &dev->dev->attrs;
struct ib_qp_init_attr *init_attr;
struct ib_cq *recv_cq, *send_cq;
struct ib_qp *qp;
@@ -583,12 +584,14 @@ static int srp_create_ch_ib(struct srp_r
init_attr->cap.max_send_wr = m * target->queue_size;
init_attr->cap.max_recv_wr = target->queue_size + 1;
init_attr->cap.max_recv_sge = 1;
- init_attr->cap.max_send_sge = SRP_MAX_SGE;
+ init_attr->cap.max_send_sge = min(SRP_MAX_SGE, attr->max_send_sge);
init_attr->sq_sig_type = IB_SIGNAL_REQ_WR;
init_attr->qp_type = IB_QPT_RC;
init_attr->send_cq = send_cq;
init_attr->recv_cq = recv_cq;
+ ch->max_imm_sge = min(init_attr->cap.max_send_sge - 1U, 255U);
+
if (target->using_rdma_cm) {
ret = rdma_create_qp(ch->rdma_cm.cm_id, dev->pd, init_attr);
qp = ch->rdma_cm.cm_id->qp;
@@ -1838,7 +1841,7 @@ static int srp_map_data(struct scsi_cmnd
return -EIO;
if (ch->use_imm_data &&
- count <= SRP_MAX_IMM_SGE &&
+ count <= ch->max_imm_sge &&
SRP_IMM_DATA_OFFSET + data_len <= ch->max_it_iu_len &&
scmnd->sc_data_direction == DMA_TO_DEVICE) {
struct srp_imm_buf *buf;
--- a/drivers/infiniband/ulp/srp/ib_srp.h
+++ b/drivers/infiniband/ulp/srp/ib_srp.h
@@ -161,6 +161,7 @@ struct srp_rdma_ch {
};
uint32_t max_it_iu_len;
uint32_t max_ti_iu_len;
+ u8 max_imm_sge;
bool use_imm_data;
/* Everything above this point is used in the hot path of