net/mlx5: Disable SRIOV before PF removal

Virtual functions depend on physical function for device access (for example
firmware host PAGE management), so make sure to disable SR-IOV once PF is gone.

This will prevent also the below warning if PF has gone before disabling SR-IOV.
"driver left SR-IOV enabled after remove"

Next patch from this series will rely on that when the VF may need to
access safely the PF 'driver data'.

Link: https://lore.kernel.org/all/20220224142024.147653-4-yishaih@nvidia.com
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/main.c

@@ -1620,6 +1620,7 @@ static void remove_one(struct pci_dev *pdev)
 	struct devlink *devlink = priv_to_devlink(dev);
 
 	devlink_unregister(devlink);
+	mlx5_sriov_disable(pdev);
 	mlx5_crdump_disable(dev);
 	mlx5_drain_health_wq(dev);
 	mlx5_uninit_one(dev);

drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.h

@@ -164,6 +164,7 @@ void mlx5_sriov_cleanup(struct mlx5_core_dev *dev);
 int mlx5_sriov_attach(struct mlx5_core_dev *dev);
 void mlx5_sriov_detach(struct mlx5_core_dev *dev);
 int mlx5_core_sriov_configure(struct pci_dev *dev, int num_vfs);
+void mlx5_sriov_disable(struct pci_dev *pdev);
 int mlx5_core_sriov_set_msix_vec_count(struct pci_dev *vf, int msix_vec_count);
 int mlx5_core_enable_hca(struct mlx5_core_dev *dev, u16 func_id);
 int mlx5_core_disable_hca(struct mlx5_core_dev *dev, u16 func_id);

drivers/net/ethernet/mellanox/mlx5/core/sriov.c

@@ -161,7 +161,7 @@ static int mlx5_sriov_enable(struct pci_dev *pdev, int num_vfs)
 	return err;
 }
 
-static void mlx5_sriov_disable(struct pci_dev *pdev)
+void mlx5_sriov_disable(struct pci_dev *pdev)
 {
 	struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
 	int num_vfs = pci_num_vf(dev->pdev);