From 2007722a606bf9f195217f7afd2fbee4bc202c42 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Fri, 7 Dec 2012 13:43:50 -0700 Subject: [PATCH] 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 --- drivers/vfio/pci/vfio_pci.c | 43 ++++++++++++++++++++++++++----------- 1 file changed, 31 insertions(+), 12 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index a4dc21b9cb06..b179f5a357f6 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -92,9 +92,10 @@ out: 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 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev) 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) -- 2.34.1