IB/mlx5: Fix blue flame buffer size calculation

A blue flame register is comprised of two buffers of equal size.

Fixes: 5fe9dec0d0454 ("IB/mlx5: Use blue flame register allocator in mlx5_ib")
Signed-off-by: Eli Cohen <[email protected]>
Reviewed-by: Noa Osherovich <[email protected]>
Reviewed-by: Matan Barak <[email protected]>
Signed-off-by: Leon Romanovsky <[email protected]>
Signed-off-by: Doug Ledford <[email protected]>

diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index fbfff1269816ee79783daed22448b9507cfea473..69a1604a887c4a91f6c6ff3cf61f17790a668c72 100644 (file)
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -905,7 +905,10 @@ static int create_kernel_qp(struct mlx5_ib_dev *dev,
        else
                qp->bf.bfreg = &dev->bfreg;
 
-       qp->bf.buf_size = 1 << MLX5_CAP_GEN(dev->mdev, log_bf_reg_size);
+       /* We need to divide by two since each register is comprised of
+        * two buffers of identical size, namely odd and even
+        */
+       qp->bf.buf_size = (1 << MLX5_CAP_GEN(dev->mdev, log_bf_reg_size)) / 2;
        uar_index = qp->bf.bfreg->index;
 
        err = calc_sq_size(dev, init_attr, qp);