> From: Yi Liu <yi.l.liu@xxxxxxxxx> > Sent: Thursday, September 21, 2023 3:51 PM > + > +/** > + * iommu_copy_user_data - Copy iommu driver specific user space data > + * @dst_data: Pointer to an iommu driver specific user data that is defined > in > + * include/uapi/linux/iommufd.h > + * @src_data: Pointer to a struct iommu_user_data for user space data info > + * @data_len: Length of current user data structure, i.e. sizeof(struct _dst) > + * @min_len: Initial length of user data structure for backward compatibility. > + * This should be offsetofend using the last member in the user data > + * struct that was initially added to include/uapi/linux/iommufd.h > + */ > +static inline int iommu_copy_user_data(void *dst_data, > + const struct iommu_user_data *src_data, > + size_t data_len, size_t min_len) iommu_copy_struct_from_user()? btw given the confusion raised on how this would be used is it clearer to move it to the patch together with the 1st user?