net/mlx5: Simplify sriov enable/disable flow

Simplify sriov enable/disable flow for below two checks.

1. PCI core driver allows sriov configuration only on a PF.
This is done in drivers/pci/pci-sysfs.c sriov_attrs_are_visible().

2. PCI core driver allow sriov enablement if the sriov is currently
disabled for for a PF. This is done in drivers/pci/pci-sysfs.c
sriov_numvfs_store().

Hence there is no need for mlx5 driver to duplicate such checks.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Bodong Wang <bodong@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

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

@@ -151,33 +151,10 @@ static void mlx5_device_disable_sriov(struct mlx5_core_dev *dev)
 		mlx5_core_warn(dev, "timeout reclaiming VFs pages\n");
 }
 
-static int mlx5_pci_enable_sriov(struct pci_dev *pdev, int num_vfs)
-{
-	struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
-	int err = 0;
-
-	if (pci_num_vf(pdev)) {
-		mlx5_core_warn(dev, "Unable to enable pci sriov, already enabled\n");
-		return -EBUSY;
-	}
-
-	err = pci_enable_sriov(pdev, num_vfs);
-	if (err)
-		mlx5_core_warn(dev, "pci_enable_sriov failed : %d\n", err);
-
-	return err;
-}
-
-static void mlx5_pci_disable_sriov(struct pci_dev *pdev)
-{
-	pci_disable_sriov(pdev);
-}
-
 static int mlx5_sriov_enable(struct pci_dev *pdev, int num_vfs)
 {
 	struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
-	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
-	int err = 0;
+	int err;
 
 	err = mlx5_device_enable_sriov(dev, num_vfs);
 	if (err) {
@@ -185,42 +162,37 @@ static int mlx5_sriov_enable(struct pci_dev *pdev, int num_vfs)
 		return err;
 	}
 
-	err = mlx5_pci_enable_sriov(pdev, num_vfs);
+	err = pci_enable_sriov(pdev, num_vfs);
 	if (err) {
-		mlx5_core_warn(dev, "mlx5_pci_enable_sriov failed : %d\n", err);
+		mlx5_core_warn(dev, "pci_enable_sriov failed : %d\n", err);
 		mlx5_device_disable_sriov(dev);
-		return err;
 	}
-
-	sriov->num_vfs = num_vfs;
-
-	return 0;
+	return err;
 }
 
 static void mlx5_sriov_disable(struct pci_dev *pdev)
 {
 	struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
-	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
 
-	mlx5_pci_disable_sriov(pdev);
+	pci_disable_sriov(pdev);
 	mlx5_device_disable_sriov(dev);
-	sriov->num_vfs = 0;
 }
 
 int mlx5_core_sriov_configure(struct pci_dev *pdev, int num_vfs)
 {
 	struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
+	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
 	int err = 0;
 
 	mlx5_core_dbg(dev, "requested num_vfs %d\n", num_vfs);
-	if (!mlx5_core_is_pf(dev))
-		return -EPERM;
 
 	if (num_vfs)
 		err = mlx5_sriov_enable(pdev, num_vfs);
 	else
 		mlx5_sriov_disable(pdev);
 
+	if (!err)
+		sriov->num_vfs = num_vfs;
 	return err ? err : num_vfs;
 }