IB/ehca: Update qp_state on cached modify_qp()

Since the introduction of the port auto-detect mode for ehca, calls to
modify_qp() may be cached in the device driver when the ports are not
activated yet. When a modify_qp() call is cached, the qp state remains
untouched until the port is activated, which will leave the qp in the
reset state. In the reset state, however, it is not allowed to post SQ
WQEs, which confuses applications like ib_mad.

The solution for this problem is to immediately set the qp state as
requested by modify_qp(), even when the call is cached.
Signed-off-by: NAlexander Schmidt <alexs@linux.vnet.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

drivers/infiniband/hw/ehca/ehca_qp.c

@@ -1534,8 +1534,6 @@ static int internal_modify_qp(struct ib_qp *ibqp,
 	if (attr_mask & IB_QP_QKEY)
 		my_qp->qkey = attr->qkey;
 
-	my_qp->state = qp_new_state;
-
 modify_qp_exit2:
 	if (squeue_locked) { /* this means: sqe -> rts */
 		spin_unlock_irqrestore(&my_qp->spinlock_s, flags);
@@ -1551,6 +1549,8 @@ static int internal_modify_qp(struct ib_qp *ibqp,
 int ehca_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, int attr_mask,
 		   struct ib_udata *udata)
 {
+	int ret = 0;
+
 	struct ehca_shca *shca = container_of(ibqp->device, struct ehca_shca,
 					      ib_device);
 	struct ehca_qp *my_qp = container_of(ibqp, struct ehca_qp, ib_qp);
@@ -1597,12 +1597,18 @@ int ehca_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, int attr_mask,
 				 attr->qp_state, my_qp->init_attr.port_num,
 				 ibqp->qp_type);
 			spin_unlock_irqrestore(&sport->mod_sqp_lock, flags);
-			return 0;
+			goto out;
 		}
 		spin_unlock_irqrestore(&sport->mod_sqp_lock, flags);
 	}
 
-	return internal_modify_qp(ibqp, attr, attr_mask, 0);
+	ret = internal_modify_qp(ibqp, attr, attr_mask, 0);
+
+out:
+	if ((ret == 0) && (attr_mask & IB_QP_STATE))
+		my_qp->state = attr->qp_state;
+
+	return ret;
 }
 
 void ehca_recover_sqp(struct ib_qp *sqp)