[PATCH 5.10 251/717] RDMA/hns: Fix 0-length sge calculation error

Greg Kroah-Hartman
2020-12-28T14:11:53Z

From: Lang Cheng <chenglang@huawei.com>

[ Upstream commit 0fd0175e30e487f8d70ecb2cdd67fbb514fdf50f ]

One RC SQ WQE can store 2 sges but UD can't, so ignore 2 valid sges of
wr.sglist for RC which have been filled in WQE before setting extended
sge. Either of RC and UD can not contain 0-length sges, so these 0-length
sges should be skipped.

Fixes: 54d6638765b0 ("RDMA/hns: Optimize WQE buffer size calculating process")
Link: https://lore.kernel.org/r/1606558959-48510-2-git-send-email-liweihang@huawei.com
Signed-off-by: Lang Cheng <chenglang@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/infiniband/hw/hns/hns_roce_hw_v2.c | 24 +++++++++-------------
1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
index 4db7eea3dcec5..c287dbd2f384d 100644
--- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
+++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
@@ -214,25 +214,20 @@ static int fill_ext_sge_inl_data(struct hns_roce_qp *qp,
return 0;
}

-static void set_extend_sge(struct hns_roce_qp *qp, const struct ib_send_wr *wr,
- unsigned int *sge_ind, unsigned int valid_num_sge)
+static void set_extend_sge(struct hns_roce_qp *qp, struct ib_sge *sge,
+ unsigned int *sge_ind, unsigned int cnt)
{
struct hns_roce_v2_wqe_data_seg *dseg;
- unsigned int cnt = valid_num_sge;
- struct ib_sge *sge = wr->sg_list;
unsigned int idx = *sge_ind;

- if (qp->ibqp.qp_type == IB_QPT_RC || qp->ibqp.qp_type == IB_QPT_UC) {
- cnt -= HNS_ROCE_SGE_IN_WQE;
- sge += HNS_ROCE_SGE_IN_WQE;
- }
-
while (cnt > 0) {
dseg = hns_roce_get_extend_sge(qp, idx & (qp->sge.sge_cnt - 1));
- set_data_seg_v2(dseg, sge);
- idx++;
+ if (likely(sge->length)) {
+ set_data_seg_v2(dseg, sge);
+ idx++;
+ cnt--;
+ }
sge++;
- cnt--;
}

*sge_ind = idx;
@@ -340,7 +335,8 @@ static int set_rwqe_data_seg(struct ib_qp *ibqp, const struct ib_send_wr *wr,
}
}

- set_extend_sge(qp, wr, sge_ind, valid_num_sge);
+ set_extend_sge(qp, wr->sg_list + i, sge_ind,
+ valid_num_sge - HNS_ROCE_SGE_IN_WQE);
}

roce_set_field(rc_sq_wqe->byte_16,
@@ -511,7 +507,7 @@ static inline int set_ud_wqe(struct hns_roce_qp *qp,

memcpy(&ud_sq_wqe->dgid[0], &ah->av.dgid[0], GID_LEN_V2);

- set_extend_sge(qp, wr, &curr_idx, valid_num_sge);
+ set_extend_sge(qp, wr->sg_list, &curr_idx, valid_num_sge);

*sge_idx = curr_idx;

--
2.27.0