diff options
Diffstat (limited to 'drivers/iommu/iommu.c')
| -rw-r--r-- | drivers/iommu/iommu.c | 50 |
1 files changed, 48 insertions, 2 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 770ba7e7ef4d..cf7ca7e70777 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -1105,8 +1105,12 @@ static int iommu_bus_notifier(struct notifier_block *nb, * result in ADD/DEL notifiers to group->notifier */ if (action == BUS_NOTIFY_ADD_DEVICE) { - if (ops->add_device) - return ops->add_device(dev); + if (ops->add_device) { + int ret; + + ret = ops->add_device(dev); + return (ret) ? NOTIFY_DONE : NOTIFY_OK; + } } else if (action == BUS_NOTIFY_REMOVED_DEVICE) { if (ops->remove_device && dev->iommu_group) { ops->remove_device(dev); @@ -1674,6 +1678,48 @@ void iommu_domain_window_disable(struct iommu_domain *domain, u32 wnd_nr) } EXPORT_SYMBOL_GPL(iommu_domain_window_disable); +/** + * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework + * @domain: the iommu domain where the fault has happened + * @dev: the device where the fault has happened + * @iova: the faulting address + * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...) + * + * This function should be called by the low-level IOMMU implementations + * whenever IOMMU faults happen, to allow high-level users, that are + * interested in such events, to know about them. + * + * This event may be useful for several possible use cases: + * - mere logging of the event + * - dynamic TLB/PTE loading + * - if restarting of the faulting device is required + * + * Returns 0 on success and an appropriate error code otherwise (if dynamic + * PTE/TLB loading will one day be supported, implementations will be able + * to tell whether it succeeded or not according to this return value). + * + * Specifically, -ENOSYS is returned if a fault handler isn't installed + * (though fault handlers can also return -ENOSYS, in case they want to + * elicit the default behavior of the IOMMU drivers). + */ +int report_iommu_fault(struct iommu_domain *domain, struct device *dev, + unsigned long iova, int flags) +{ + int ret = -ENOSYS; + + /* + * if upper layers showed interest and installed a fault handler, + * invoke it. + */ + if (domain->handler) + ret = domain->handler(domain, dev, iova, flags, + domain->handler_token); + + trace_io_page_fault(dev, iova, flags); + return ret; +} +EXPORT_SYMBOL_GPL(report_iommu_fault); + static int __init iommu_init(void) { iommu_group_kset = kset_create_and_add("iommu_groups", |