From: Moni Shoua <monis@mellanox.com>
Date: Tue, 30 May 2017 09:56:05 +0300
Subject: IB/mlx5: Change logic for dispatching IB events for port state
Patch-mainline: v4.14-rc1
Git-commit: fd65f1b8eefdd20bd70cc920a7306e1e1b113d81
References: bsc#1046305 FATE#322943

The old logic ignored link state. This led to missing IB events like
when link goes down on the switch while admin state is up or to redundant
events like when admin state goes up while link is down.
To fix that, probe the port state on NETDEV events and compare to last
known state to decide if IB events needs to be dispatched.

FIxes: 5ec8c83e3ad3 ("IB/mlx5: Port events in RoCE now rely on netdev events")
Signed-off-by: Moni Shoua <monis@mellanox.com>
Reviewed-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/hw/mlx5/main.c    |   33 +++++++++++++++++++++++++++++++--
 drivers/infiniband/hw/mlx5/mlx5_ib.h |    1 +
 2 files changed, 32 insertions(+), 2 deletions(-)

--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -98,6 +98,20 @@ mlx5_ib_port_link_layer(struct ib_device
 	return mlx5_port_type_cap_to_rdma_ll(port_type_cap);
 }
 
+static int get_port_state(struct ib_device *ibdev,
+			  u8 port_num,
+			  enum ib_port_state *state)
+{
+	struct ib_port_attr attr;
+	int ret;
+
+	memset(&attr, 0, sizeof(attr));
+	ret = mlx5_ib_query_port(ibdev, port_num, &attr);
+	if (!ret)
+		*state = attr.state;
+	return ret;
+}
+
 static int mlx5_netdev_event(struct notifier_block *this,
 			     unsigned long event, void *ptr)
 {
@@ -115,6 +129,7 @@ static int mlx5_netdev_event(struct noti
 		write_unlock(&ibdev->roce.netdev_lock);
 		break;
 
+	case NETDEV_CHANGE:
 	case NETDEV_UP:
 	case NETDEV_DOWN: {
 		struct net_device *lag_ndev = mlx5_lag_get_roce_netdev(ibdev->mdev);
@@ -128,10 +143,23 @@ static int mlx5_netdev_event(struct noti
 		if ((upper == ndev || (!upper && ndev == ibdev->roce.netdev))
 		    && ibdev->ib_active) {
 			struct ib_event ibev = { };
+			enum ib_port_state port_state;
 
+			if (get_port_state(&ibdev->ib_dev, 1, &port_state))
+				return NOTIFY_DONE;
+
+			if (ibdev->roce.last_port_state == port_state)
+				return NOTIFY_DONE;
+
+			ibdev->roce.last_port_state = port_state;
 			ibev.device = &ibdev->ib_dev;
-			ibev.event = (event == NETDEV_UP) ?
-				     IB_EVENT_PORT_ACTIVE : IB_EVENT_PORT_ERR;
+			if (port_state == IB_PORT_DOWN)
+				ibev.event = IB_EVENT_PORT_ERR;
+			else if (port_state == IB_PORT_ACTIVE)
+				ibev.event = IB_EVENT_PORT_ACTIVE;
+			else
+				return NOTIFY_DONE;
+
 			ibev.element.port_num = 1;
 			ib_dispatch_event(&ibev);
 		}
@@ -3799,6 +3827,7 @@ static void *mlx5_ib_add(struct mlx5_cor
 		err = mlx5_enable_eth(dev);
 		if (err)
 			goto err_free_port;
+		dev->roce.last_port_state = IB_PORT_DOWN;
 	}
 
 	err = create_dev_resources(&dev->devr);
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -616,6 +616,7 @@ struct mlx5_roce {
 	struct net_device	*netdev;
 	struct notifier_block	nb;
 	atomic_t		next_port;
+	enum ib_port_state last_port_state;
 };
 
 struct mlx5_ib_dev {