On Fri, May 19, 2023 at 08:47:45AM +0000, Tian, Kevin wrote:
From: Liu, Yi L yi.l.liu@intel.com Sent: Thursday, May 11, 2023 10:39 PM @@ -229,6 +238,15 @@ struct iommu_iotlb_gather {
after use. Return the data buffer if success, or ERR_PTR onfailure.- @domain_alloc: allocate iommu domain
- @domain_alloc_user: allocate user iommu domain
- @domain_alloc_user_data_len: return the required length of the user
data
to allocate a specific type user iommu domain.
@hwpt_type is defined as enum iommu_hwpt_type
in include/uapi/linux/iommufd.h. The returned
length is the corresponding sizeof driver data
structures in include/uapi/linux/iommufd.h.
-EOPNOTSUPP would be returned if the input
@hwpt_type is not supported by the driver.Can this be merged with earlier @hw_info callback? That will already report a list of supported hwpt types. is there a problem to further describe the data length for each type in that interface?
Yi and I had a last minute talk before he sent this version actually... This version of hw_info no longer reports a list of supported hwpt types. We previously did that in a bitmap, but we found that a bitmap will not be sufficient eventually if there are more than 64 hwpt_types.
And this domain_alloc_user_data_len might not be necessary, because in this version the IOMMUFD core doesn't really care about the actual data_len since it copies the data into the ucmd_buffer, i.e. we would probably only need a bool op like "hwpt_type_is_supported".
Thanks Nic