diff options
Diffstat (limited to 'drivers/xen/xen-pciback/pci_stub.c')
| -rw-r--r-- | drivers/xen/xen-pciback/pci_stub.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c index 62fcd485f0a7..d57a173685f3 100644 --- a/drivers/xen/xen-pciback/pci_stub.c +++ b/drivers/xen/xen-pciback/pci_stub.c @@ -242,6 +242,15 @@ struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev, return found_dev; } +/* + * Called when: + * - XenBus state has been reconfigure (pci unplug). See xen_pcibk_remove_device + * - XenBus state has been disconnected (guest shutdown). See xen_pcibk_xenbus_remove + * - 'echo BDF > unbind' on pciback module with no guest attached. See pcistub_remove + * - 'echo BDF > unbind' with a guest still using it. See pcistub_remove + * + * As such we have to be careful. + */ void pcistub_put_pci_dev(struct pci_dev *dev) { struct pcistub_device *psdev, *found_psdev = NULL; @@ -272,16 +281,16 @@ void pcistub_put_pci_dev(struct pci_dev *dev) * and want to inhibit the user from fiddling with 'reset' */ pci_reset_function(dev); - pci_restore_state(psdev->dev); + pci_restore_state(dev); /* This disables the device. */ - xen_pcibk_reset_device(found_psdev->dev); + xen_pcibk_reset_device(dev); /* And cleanup up our emulated fields. */ - xen_pcibk_config_free_dyn_fields(found_psdev->dev); - xen_pcibk_config_reset_dev(found_psdev->dev); + xen_pcibk_config_reset_dev(dev); + xen_pcibk_config_free_dyn_fields(dev); - xen_unregister_device_domain_owner(found_psdev->dev); + xen_unregister_device_domain_owner(dev); spin_lock_irqsave(&found_psdev->lock, flags); found_psdev->pdev = NULL; @@ -493,6 +502,8 @@ static int pcistub_seize(struct pci_dev *dev) return err; } +/* Called when 'bind'. This means we must _NOT_ call pci_reset_function or + * other functions that take the sysfs lock. */ static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id) { int err = 0; @@ -520,6 +531,8 @@ out: return err; } +/* Called when 'unbind'. This means we must _NOT_ call pci_reset_function or + * other functions that take the sysfs lock. */ static void pcistub_remove(struct pci_dev *dev) { struct pcistub_device *psdev, *found_psdev = NULL; @@ -551,6 +564,8 @@ static void pcistub_remove(struct pci_dev *dev) pr_warn("****** shutdown driver domain before binding device\n"); pr_warn("****** to other drivers or domains\n"); + /* N.B. This ends up calling pcistub_put_pci_dev which ends up + * doing the FLR. */ xen_pcibk_release_pci_dev(found_psdev->pdev, found_psdev->dev); } |