IB/mlx4: Avoid executing gid task when device is being removed

When device is being removed (e.g during VPI port link type change
from ETH to IB), tasks for gid table changes should not be executed.

Flush the current queue of tasks and block further tasks from entering the queue.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/hw/mlx4/main.c

@@ -1390,6 +1390,9 @@ static void update_gids_task(struct work_struct *work)
 	int err;
 	struct mlx4_dev	*dev = gw->dev->dev;
 
+	if (!gw->dev->ib_active)
+		return;
+
 	mailbox = mlx4_alloc_cmd_mailbox(dev);
 	if (IS_ERR(mailbox)) {
 		pr_warn("update gid table failed %ld\n", PTR_ERR(mailbox));
@@ -1420,6 +1423,9 @@ static void reset_gids_task(struct work_struct *work)
 	int err;
 	struct mlx4_dev	*dev = gw->dev->dev;
 
+	if (!gw->dev->ib_active)
+		return;
+
 	mailbox = mlx4_alloc_cmd_mailbox(dev);
 	if (IS_ERR(mailbox)) {
 		pr_warn("reset gid table failed\n");
@@ -2369,6 +2375,9 @@ static void mlx4_ib_remove(struct mlx4_dev *dev, void *ibdev_ptr)
 	struct mlx4_ib_dev *ibdev = ibdev_ptr;
 	int p;
 
+	ibdev->ib_active = false;
+	flush_workqueue(wq);
+
 	mlx4_ib_close_sriov(ibdev);
 	mlx4_ib_mad_cleanup(ibdev);
 	ib_unregister_device(&ibdev->ib_dev);