27 Jul
2023
27 Jul
'23
7:57 a.m.
From: Liu, Yi L yi.l.liu@intel.com Sent: Monday, July 24, 2023 7:00 PM
@@ -252,11 +258,20 @@ struct iommu_iotlb_gather {
- @remove_dev_pasid: Remove any translation configurations of a specific
pasid, so that any DMA transactions with this pasidwill be blocked by the hardware.
- @hw_info_type: One of enum iommu_hw_info_type defined in
include/uapi/linux/iommufd.h. It is used to tag the type
of data returned by .hw_info callback. The drivers that
support .hw_info callback should define a unique type
in include/uapi/linux/iommufd.h. For the drivers that do
not implement .hw_info callback, this field is
IOMMU_HW_INFO_TYPE_NONE which is 0. Hence, such drivers
do not need to care this field.
every time looking at this field the same question came out why it is required (and looks I forgot your previous response).
e.g. why cannot the type be returned in @hw_info():
void *(*hw_info)(struct device *dev, u32 *length, int *type);
NULL callback implies IOMMU_HW_INFO_TYPE_NONE.
otherwise if there is a reason could you update the commit msg to reflect it so I don't need to ask again next time? 😊