[PATCH v2 net-next 5/5] ionic: add lif_quiesce to wait for queue activity to stop

[Shannon Nelson <snelson@pensando.io>]

Even though we've already turned off the queue activity with
the ionic_qcq_disable(), we need to wait for any device queues
that are processing packets to drain down before we try to
flush our packets and tear down the queues.

Signed-off-by: Shannon Nelson <snelson@pensando.io>
---
 .../net/ethernet/pensando/ionic/ionic_lif.c   | 24 +++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_lif.c b/drivers/net/ethernet/pensando/ionic/ionic_lif.c
index 372329389c84..fc4ab73bd608 100644
--- a/drivers/net/ethernet/pensando/ionic/ionic_lif.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_lif.c
@@ -242,6 +242,29 @@ static int ionic_qcq_disable(struct ionic_qcq *qcq)
 	return ionic_adminq_post_wait(lif, &ctx);
 }
 
+static int ionic_lif_quiesce(struct ionic_lif *lif)
+{
+	int err;
+	struct device *dev = lif->ionic->dev;
+	struct ionic_admin_ctx ctx = {
+		.work = COMPLETION_INITIALIZER_ONSTACK(ctx.work),
+		.cmd.lif_setattr = {
+			.opcode = IONIC_CMD_LIF_SETATTR,
+			.attr = IONIC_LIF_ATTR_STATE,
+			.index = lif->index,
+			.state = IONIC_LIF_DISABLE
+		},
+	};
+
+	err = ionic_adminq_post_wait(lif, &ctx);
+	if (err) {
+		dev_err(dev, "failed to quiesce lif, error = %d\n", err);
+		return err;
+	}
+
+	return (0);
+}
+
 static void ionic_lif_qcq_deinit(struct ionic_lif *lif, struct ionic_qcq *qcq)
 {
 	struct ionic_dev *idev = &lif->ionic->idev;
@@ -1589,6 +1612,7 @@ int ionic_stop(struct net_device *netdev)
 	netif_tx_disable(netdev);
 
 	ionic_txrx_disable(lif);
+	ionic_lif_quiesce(lif);
 	ionic_txrx_deinit(lif);
 	ionic_txrx_free(lif);
 
-- 
2.17.1