IB/mthca: Fix corner cases in max_rd_atomic value handling in modify QP

sae and sre bits should only be set when setting sra_max.  Further, in
the old code, if the caller specifies max_rd_atomic = 0, the sre and
sae bits are still set, with the result that the QP ends up with
max_rd_atomic = 1 in effect.

Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_qp.c b/drivers/infiniband/hw/mthca/mthca_qp.c
index e826c9ff5d70..d786ef443614 100644
--- a/drivers/infiniband/hw/mthca/mthca_qp.c
+++ b/drivers/infiniband/hw/mthca/mthca_qp.c
@@ -747,9 +747,7 @@ int mthca_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, int attr_mask)
         qp_context->wqe_lkey   = cpu_to_be32(qp->mr.ibmr.lkey);
         qp_context->params1    = cpu_to_be32((MTHCA_ACK_REQ_FREQ << 28) |
                                              (MTHCA_FLIGHT_LIMIT << 24) |
-                                             MTHCA_QP_BIT_SRE           |
-                                             MTHCA_QP_BIT_SWE           |
-                                             MTHCA_QP_BIT_SAE);
+                                             MTHCA_QP_BIT_SWE);
         if (qp->sq_policy == IB_SIGNAL_ALL_WR)
                 qp_context->params1 |= cpu_to_be32(MTHCA_QP_BIT_SSC);
         if (attr_mask & IB_QP_RETRY_CNT) {
@@ -758,9 +756,13 @@ int mthca_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, int attr_mask)
         }
 
         if (attr_mask & IB_QP_MAX_QP_RD_ATOMIC) {
-                if (attr->max_rd_atomic)
+                if (attr->max_rd_atomic) {
+                        qp_context->params1 |=
+                                cpu_to_be32(MTHCA_QP_BIT_SRE |
+                                            MTHCA_QP_BIT_SAE);
                         qp_context->params1 |=
                                 cpu_to_be32(fls(attr->max_rd_atomic - 1) << 21);
+                }
                 qp_param->opt_param_mask |= cpu_to_be32(MTHCA_QP_OPTPAR_SRA_MAX);
         }