On Sat, Jun 14, 2025 at 12:14:42AM -0700, Nicolin Chen wrote:
The iommu_hw_info can output via the out_data_type field the vendor data type from a driver, but this only allows driver to report one data type.
Now, with SMMUv3 having a Tegra241 CMDQV implementation, it has two sets of types and data structs to report.
One way to support that is to use the same type field bidirectionally.
Reuse the same field by adding an "in_data_type", allowing user space to request for a specific type and to get the corresponding data.
For backward compatibility, since the ioctl handler has never checked an input value, add an IOMMU_HW_INFO_FLAG_INPUT_TYPE to switch between the old output-only field and the new bidirectional field.
Reviewed-by: Kevin Tian kevin.tian@intel.com Signed-off-by: Nicolin Chen nicolinc@nvidia.com
include/uapi/linux/iommufd.h | 20 +++++++++++++++++++- drivers/iommu/iommufd/device.c | 9 ++++++--- 2 files changed, 25 insertions(+), 4 deletions(-)
Reviewed-by: Jason Gunthorpe jgg@nvidia.com
Jason