[IPoIB] cleanups: fix comment, remove useless variables

Minor cleanups: fix a misleading comment, and get rid of attr_mask
variables that are only used to hold constants (just use the constants
directly).

Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/ulp/ipoib/ipoib_ib.c

@@ -486,15 +486,16 @@ int ipoib_ib_dev_stop(struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ib_qp_attr qp_attr;
-	int attr_mask;
 	unsigned long begin;
 	struct ipoib_tx_buf *tx_req;
 	int i;
 
-	/* Kill the existing QP and allocate a new one */
+	/*
+	 * Move our QP to the error state and then reinitialize in
+	 * when all work requests have completed or have been flushed.
+	 */
 	qp_attr.qp_state = IB_QPS_ERR;
-	attr_mask        = IB_QP_STATE;
-	if (ib_modify_qp(priv->qp, &qp_attr, attr_mask))
+	if (ib_modify_qp(priv->qp, &qp_attr, IB_QP_STATE))
 		ipoib_warn(priv, "Failed to modify QP to ERROR state\n");
 
 	/* Wait for all sends and receives to complete */
@@ -541,8 +542,7 @@ int ipoib_ib_dev_stop(struct net_device *dev)
 
 timeout:
 	qp_attr.qp_state = IB_QPS_RESET;
-	attr_mask        = IB_QP_STATE;
-	if (ib_modify_qp(priv->qp, &qp_attr, attr_mask))
+	if (ib_modify_qp(priv->qp, &qp_attr, IB_QP_STATE))
 		ipoib_warn(priv, "Failed to modify QP to RESET state\n");
 
 	/* Wait for all AHs to be reaped */

drivers/infiniband/ulp/ipoib/ipoib_verbs.c

@@ -41,7 +41,6 @@ int ipoib_mcast_attach(struct net_device *dev, u16 mlid, union ib_gid *mgid)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ib_qp_attr *qp_attr;
-	int attr_mask;
 	int ret;
 	u16 pkey_index;
 
@@ -59,8 +58,7 @@ int ipoib_mcast_attach(struct net_device *dev, u16 mlid, union ib_gid *mgid)
 
 	/* set correct QKey for QP */
 	qp_attr->qkey = priv->qkey;
-	attr_mask = IB_QP_QKEY;
-	ret = ib_modify_qp(priv->qp, qp_attr, attr_mask);
+	ret = ib_modify_qp(priv->qp, qp_attr, IB_QP_QKEY);
 	if (ret) {
 		ipoib_warn(priv, "failed to modify QP, ret = %d\n", ret);
 		goto out;