On Thu, May 15, 2025 at 02:17:06PM -0300, Jason Gunthorpe wrote:
On Thu, May 08, 2025 at 08:02:39PM -0700, Nicolin Chen wrote:
Repurpose the @__reserved field in the struct iommu_hw_info_arm_smmuv3, to an HW implementation-defined field @impl.
It would be nicer to have a tegra/cmdq specific struct and a way for iommu_hw_info to select it. 'impl' isn't going to scale very well if something else wants to use this.
We have out_data_type but we could have an input sub_data_type too. 0 means what we have today, then a simple enum to select another info struct.
So, there will be two hw_info calls back to back right?
Should the first call return out_data_type=CMDQV while returning the arm_smmu_v3 hw_info data? Otherwise, VMM wouldn't know what to set in the input sub_data_type of the 2nd ioctl?
Thanks Nicolin