From: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> DMA faults can be detected by IOMMU at device level. Adding a pointer to struct device allows IOMMU subsystem to report relevant faults back to the device driver for further handling. For direct assigned device (or user space drivers), guest OS holds responsibility to handle and respond per device IOMMU fault. Therefore we need fault reporting mechanism to propagate faults beyond IOMMU subsystem. There are two other IOMMU data pointers under struct device today, here we introduce iommu_param as a parent pointer such that all device IOMMU data can be consolidated here. The idea was suggested here by Greg KH and Joerg. The name iommu_param is chosen here since iommu_data has been used. Suggested-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> Link: https://lkml.org/lkml/2017/10/6/81 --- include/linux/device.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/include/linux/device.h b/include/linux/device.h index 4e6987e11f68..2cd48a6c5181 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -42,6 +42,7 @@ struct iommu_ops; struct iommu_group; struct iommu_fwspec; struct dev_pin_info; +struct iommu_param; struct bus_attribute { struct attribute attr; @@ -959,6 +960,7 @@ struct dev_links_info { * device (i.e. the bus driver that discovered the device). * @iommu_group: IOMMU group the device belongs to. * @iommu_fwspec: IOMMU-specific properties supplied by firmware. + * @iommu_param: Per device generic IOMMU runtime data * * @offline_disabled: If set, the device is permanently online. * @offline: Set after successful invocation of bus type's .offline(). @@ -1052,6 +1054,7 @@ struct device { void (*release)(struct device *dev); struct iommu_group *iommu_group; struct iommu_fwspec *iommu_fwspec; + struct iommu_param *iommu_param; bool offline_disabled:1; bool offline:1; -- 2.20.1
