vfio-pci: Re-order device reset
Move the device reset to the end of our disable path, the device
should already be stopped from pci_disable_device(). This also allows
us to manipulate the save/restore to avoid the save/reset/restore +
save/restore that we had before.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index a4dc21b..b179f5a 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -92,9 +92,10 @@
static void vfio_pci_disable(struct vfio_pci_device *vdev)
{
+ struct pci_dev *pdev = vdev->pdev;
int bar;
- pci_disable_device(vdev->pdev);
+ pci_disable_device(pdev);
vfio_pci_set_irqs_ioctl(vdev, VFIO_IRQ_SET_DATA_NONE |
VFIO_IRQ_SET_ACTION_TRIGGER,
@@ -104,22 +105,40 @@
vfio_config_free(vdev);
- pci_reset_function(vdev->pdev);
-
- if (pci_load_and_free_saved_state(vdev->pdev,
- &vdev->pci_saved_state) == 0)
- pci_restore_state(vdev->pdev);
- else
- pr_info("%s: Couldn't reload %s saved state\n",
- __func__, dev_name(&vdev->pdev->dev));
-
for (bar = PCI_STD_RESOURCES; bar <= PCI_STD_RESOURCE_END; bar++) {
if (!vdev->barmap[bar])
continue;
- pci_iounmap(vdev->pdev, vdev->barmap[bar]);
- pci_release_selected_regions(vdev->pdev, 1 << bar);
+ pci_iounmap(pdev, vdev->barmap[bar]);
+ pci_release_selected_regions(pdev, 1 << bar);
vdev->barmap[bar] = NULL;
}
+
+ /*
+ * If we have saved state, restore it. If we can reset the device,
+ * even better. Resetting with current state seems better than
+ * nothing, but saving and restoring current state without reset
+ * is just busy work.
+ */
+ if (pci_load_and_free_saved_state(pdev, &vdev->pci_saved_state)) {
+ pr_info("%s: Couldn't reload %s saved state\n",
+ __func__, dev_name(&pdev->dev));
+
+ if (!vdev->reset_works)
+ return;
+
+ pci_save_state(pdev);
+ }
+
+ /*
+ * Disable INTx and MSI, presumably to avoid spurious interrupts
+ * during reset. Stolen from pci_reset_function()
+ */
+ pci_write_config_word(pdev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE);
+
+ if (vdev->reset_works)
+ __pci_reset_function(pdev);
+
+ pci_restore_state(pdev);
}
static void vfio_pci_release(void *device_data)