diff options
| -rw-r--r-- | drivers/iommu/iommu.c | 6 | ||||
| -rw-r--r-- | include/linux/iommu.h | 6 |
2 files changed, 11 insertions, 1 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 3a072596b1b2..bd2d4d2764dd 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -43,6 +43,12 @@ EXPORT_SYMBOL_GPL(iommu_found); * iommu_set_fault_handler() - set a fault handler for an iommu domain * @domain: iommu domain * @handler: fault handler + * + * This function should be used by IOMMU users which want to be notified + * whenever an IOMMU fault happens. + * + * The fault handler itself should return 0 on success, and an appropriate + * error code otherwise. */ void iommu_set_fault_handler(struct iommu_domain *domain, iommu_fault_handler_t handler) diff --git a/include/linux/iommu.h b/include/linux/iommu.h index d084e8777e0e..ddad0ae0a433 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -98,11 +98,15 @@ extern void iommu_set_fault_handler(struct iommu_domain *domain, * 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). */ static inline int report_iommu_fault(struct iommu_domain *domain, struct device *dev, unsigned long iova, int flags) { - int ret = 0; + int ret = -ENOSYS; /* * if upper layers showed interest and installed a fault handler, |