IB/mlx5: Expose multi-packet RQ capabilities

This patch reports the device's striding RQ capabilities to
the user-space:
- min/max_single_stride_log_num_of_bytes: Log of min/max number of
  bytes in a single stride.
- min/max_single_wqe_log_num_of_strides: Log of min/max number of
  strides in a single WQE.
- supported_qpts: A bit mask to know which QP types support multi-
  packet RQ, for now only Raw Packet QPs.

Signed-off-by: Noa Osherovich <noaos@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 552f7bd..02da3f5 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -848,6 +848,22 @@ static int mlx5_ib_query_device(struct ib_device *ibdev,
 		}
 	}
 
+	if (field_avail(typeof(resp), striding_rq_caps, uhw->outlen)) {
+		resp.response_length += sizeof(resp.striding_rq_caps);
+		if (MLX5_CAP_GEN(mdev, striding_rq)) {
+			resp.striding_rq_caps.min_single_stride_log_num_of_bytes =
+				MLX5_MIN_SINGLE_STRIDE_LOG_NUM_BYTES;
+			resp.striding_rq_caps.max_single_stride_log_num_of_bytes =
+				MLX5_MAX_SINGLE_STRIDE_LOG_NUM_BYTES;
+			resp.striding_rq_caps.min_single_wqe_log_num_of_strides =
+				MLX5_MIN_SINGLE_WQE_LOG_NUM_STRIDES;
+			resp.striding_rq_caps.max_single_wqe_log_num_of_strides =
+				MLX5_MAX_SINGLE_WQE_LOG_NUM_STRIDES;
+			resp.striding_rq_caps.supported_qpts =
+				BIT(IB_QPT_RAW_PACKET);
+		}
+	}
+
 	if (uhw->outlen) {
 		err = ib_copy_to_udata(uhw, &resp, resp.response_length);