/* For needs_reset */
lockdep_assert_held(&vdev->vdev.dev_set->lock);
+ /*
+ * This function can be invoked while the power state is non-D0.
+ * This function calls __pci_reset_function_locked() which internally
+ * can use pci_pm_reset() for the function reset. pci_pm_reset() will
+ * fail if the power state is non-D0. Also, for the devices which
+ * have NoSoftRst-, the reset function can cause the PCI config space
+ * reset without restoring the original state (saved locally in
+ * 'vdev->pm_save').
+ */
+ vfio_pci_set_power_state(vdev, PCI_D0);
+
/* Stop the device from further DMA */
pci_clear_master(pdev);
return -EINVAL;
vfio_pci_zap_and_down_write_memory_lock(vdev);
+
+ /*
+ * This function can be invoked while the power state is non-D0.
+ * If pci_try_reset_function() has been called while the power
+ * state is non-D0, then pci_try_reset_function() will
+ * internally set the power state to D0 without vfio driver
+ * involvement. For the devices which have NoSoftRst-, the
+ * reset function can cause the PCI config space reset without
+ * restoring the original state (saved locally in
+ * 'vdev->pm_save').
+ */
+ vfio_pci_set_power_state(vdev, PCI_D0);
+
ret = pci_try_reset_function(vdev->pdev);
up_write(&vdev->memory_lock);
}
cur_mem = NULL;
+ /*
+ * The pci_reset_bus() will reset all the devices in the bus.
+ * The power state can be non-D0 for some of the devices in the bus.
+ * For these devices, the pci_reset_bus() will internally set
+ * the power state to D0 without vfio driver involvement.
+ * For the devices which have NoSoftRst-, the reset function can
+ * cause the PCI config space reset without restoring the original
+ * state (saved locally in 'vdev->pm_save').
+ */
+ list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list)
+ vfio_pci_set_power_state(cur, PCI_D0);
+
ret = pci_reset_bus(pdev);
err_undo:
if (!pdev)
return false;
+ /*
+ * The pci_reset_bus() will reset all the devices in the bus.
+ * The power state can be non-D0 for some of the devices in the bus.
+ * For these devices, the pci_reset_bus() will internally set
+ * the power state to D0 without vfio driver involvement.
+ * For the devices which have NoSoftRst-, the reset function can
+ * cause the PCI config space reset without restoring the original
+ * state (saved locally in 'vdev->pm_save').
+ */
+ list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list)
+ vfio_pci_set_power_state(cur, PCI_D0);
+
ret = pci_reset_bus(pdev);
if (ret)
return false;