i40iw: Tear-down connection after CQP Modify QP failure

There is no explicit tear-down sequence initiated on
connections if the Control QP OP, Modify QP to close,
fails. Fix this by triggering a driver generated
Asynchronous Event (AE) on Modify QP failures and
tear-down the connection on receipt of the AE.

This fix can be generalized to other Modify QP failures
(i.e. RTS->TERM, IDLE->RTS, etc) as any modify failure
will require a connection tear-down.

Fixes: d37498417947 ("i40iw: add files for iwarp interface")
Signed-off-by: Henry Orosco <henry.orosco@intel.com>
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/i40iw/i40iw.h

@@ -559,6 +559,7 @@ void i40iw_next_iw_state(struct i40iw_qp *iwqp,
 			 u8 state, u8 del_hash,
 			 u8 term, u8 term_len);
 int i40iw_send_syn(struct i40iw_cm_node *cm_node, u32 sendack);
+int i40iw_send_reset(struct i40iw_cm_node *cm_node);
 struct i40iw_cm_node *i40iw_find_node(struct i40iw_cm_core *cm_core,
 				      u16 rem_port,
 				      u32 *rem_addr,

drivers/infiniband/hw/i40iw/i40iw_cm.c

@@ -539,7 +539,7 @@ static struct i40iw_puda_buf *i40iw_form_cm_frame(struct i40iw_cm_node *cm_node,
  * i40iw_send_reset - Send RST packet
  * @cm_node: connection's node
  */
-static int i40iw_send_reset(struct i40iw_cm_node *cm_node)
+int i40iw_send_reset(struct i40iw_cm_node *cm_node)
 {
 	struct i40iw_puda_buf *sqbuf;
 	int flags = SET_RST | SET_ACK;

drivers/infiniband/hw/i40iw/i40iw_hw.c

@@ -352,6 +352,8 @@ void i40iw_process_aeq(struct i40iw_device *iwdev)
 			else
 				i40iw_cm_disconn(iwqp);
 			break;
+		case I40IW_AE_BAD_CLOSE:
+			/* fall through */
 		case I40IW_AE_RESET_SENT:
 			i40iw_next_iw_state(iwqp, I40IW_QP_STATE_ERROR, 1, 0, 0);
 			i40iw_cm_disconn(iwqp);

drivers/infiniband/hw/i40iw/i40iw_verbs.c

@@ -831,10 +831,10 @@ static int i40iw_query_qp(struct ib_qp *ibqp,
 void i40iw_hw_modify_qp(struct i40iw_device *iwdev, struct i40iw_qp *iwqp,
 			struct i40iw_modify_qp_info *info, bool wait)
 {
-	enum i40iw_status_code status;
 	struct i40iw_cqp_request *cqp_request;
 	struct cqp_commands_info *cqp_info;
 	struct i40iw_modify_qp_info *m_info;
+	struct i40iw_gen_ae_info ae_info;
 
 	cqp_request = i40iw_get_cqp_request(&iwdev->cqp, wait);
 	if (!cqp_request)
@@ -847,9 +847,25 @@ void i40iw_hw_modify_qp(struct i40iw_device *iwdev, struct i40iw_qp *iwqp,
 	cqp_info->post_sq = 1;
 	cqp_info->in.u.qp_modify.qp = &iwqp->sc_qp;
 	cqp_info->in.u.qp_modify.scratch = (uintptr_t)cqp_request;
-	status = i40iw_handle_cqp_op(iwdev, cqp_request);
-	if (status)
-		i40iw_pr_err("CQP-OP Modify QP fail");
+	if (!i40iw_handle_cqp_op(iwdev, cqp_request))
+		return;
+
+	switch (m_info->next_iwarp_state) {
+	case I40IW_QP_STATE_RTS:
+		if (iwqp->iwarp_state == I40IW_QP_STATE_IDLE)
+			i40iw_send_reset(iwqp->cm_node);
+		/* fall through */
+	case I40IW_QP_STATE_IDLE:
+	case I40IW_QP_STATE_TERMINATE:
+	case I40IW_QP_STATE_CLOSING:
+		ae_info.ae_code = I40IW_AE_BAD_CLOSE;
+		ae_info.ae_source = 0;
+		i40iw_gen_ae(iwdev, &iwqp->sc_qp, &ae_info, false);
+		break;
+	case I40IW_QP_STATE_ERROR:
+	default:
+		break;
+	}
 }
 
 /**
@@ -962,10 +978,6 @@ int i40iw_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 
 		iwqp->ibqp_state = attr->qp_state;
 
-		if (issue_modify_qp)
-			iwqp->iwarp_state = info.next_iwarp_state;
-		else
-			info.next_iwarp_state = iwqp->iwarp_state;
 	}
 	if (attr_mask & IB_QP_ACCESS_FLAGS) {
 		ctx_info->iwarp_info_valid = true;
@@ -1003,9 +1015,14 @@ int i40iw_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 
 	spin_unlock_irqrestore(&iwqp->lock, flags);
 
-	if (issue_modify_qp)
+	if (issue_modify_qp) {
 		i40iw_hw_modify_qp(iwdev, iwqp, &info, true);
 
+		spin_lock_irqsave(&iwqp->lock, flags);
+		iwqp->iwarp_state = info.next_iwarp_state;
+		spin_unlock_irqrestore(&iwqp->lock, flags);
+	}
+
 	if (issue_modify_qp && (iwqp->ibqp_state > IB_QPS_RTS)) {
 		if (dont_wait) {
 			if (iwqp->cm_id && iwqp->hw_tcp_state) {