i40e: implement split PCI error reset handler

This patch implements the PCI error handler reset_prepare and reset_done.
This allows us to handle function level reset.  Without this patch we
are unable to perform and recover from an FLR correctly and this will cause
VFs to be unable to recover from an FLR on the PF.
Signed-off-by: NAlan Brady <alan.brady@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_main.c

@@ -12045,6 +12045,28 @@ static pci_ers_result_t i40e_pci_error_slot_reset(struct pci_dev *pdev)
 	return result;
 }
 
+/**
+ * i40e_pci_error_reset_prepare - prepare device driver for pci reset
+ * @pdev: PCI device information struct
+ */
+static void i40e_pci_error_reset_prepare(struct pci_dev *pdev)
+{
+	struct i40e_pf *pf = pci_get_drvdata(pdev);
+
+	i40e_prep_for_reset(pf, false);
+}
+
+/**
+ * i40e_pci_error_reset_done - pci reset done, device driver reset can begin
+ * @pdev: PCI device information struct
+ */
+static void i40e_pci_error_reset_done(struct pci_dev *pdev)
+{
+	struct i40e_pf *pf = pci_get_drvdata(pdev);
+
+	i40e_reset_and_rebuild(pf, false, false);
+}
+
 /**
  * i40e_pci_error_resume - restart operations after PCI error recovery
  * @pdev: PCI device information struct
@@ -12235,6 +12257,8 @@ static int i40e_resume(struct device *dev)
 static const struct pci_error_handlers i40e_err_handler = {
 	.error_detected = i40e_pci_error_detected,
 	.slot_reset = i40e_pci_error_slot_reset,
+	.reset_prepare = i40e_pci_error_reset_prepare,
+	.reset_done = i40e_pci_error_reset_done,
 	.resume = i40e_pci_error_resume,
 };