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

[Shannon Nelson]

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 <snel...@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