From 54ce69e36c71c88f258b1a322c54343d90954858 Mon Sep 17 00:00:00 2001 From: Nicolin Chen Date: Tue, 5 Nov 2024 12:05:12 -0800 Subject: iommufd: Allow hwpt_id to carry viommu_id for IOMMU_HWPT_INVALIDATE With a vIOMMU object, use space can flush any IOMMU related cache that can be directed via a vIOMMU object. It is similar to the IOMMU_HWPT_INVALIDATE uAPI, but can cover a wider range than IOTLB, e.g. device/desciprtor cache. Allow hwpt_id of the iommu_hwpt_invalidate structure to carry a viommu_id, and reuse the IOMMU_HWPT_INVALIDATE uAPI for vIOMMU invalidations. Drivers can define different structures for vIOMMU invalidations v.s. HWPT ones. Since both the HWPT-based and vIOMMU-based invalidation pathways check own cache invalidation op, remove the WARN_ON_ONCE in the allocator. Update the uAPI, kdoc, and selftest case accordingly. Link: https://patch.msgid.link/r/b411e2245e303b8a964f39f49453a5dff280968f.1730836308.git.nicolinc@nvidia.com Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Signed-off-by: Nicolin Chen Signed-off-by: Jason Gunthorpe --- include/uapi/linux/iommufd.h | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index 9b5236004b8e..badb41c5bfa4 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -700,7 +700,7 @@ struct iommu_hwpt_vtd_s1_invalidate { /** * struct iommu_hwpt_invalidate - ioctl(IOMMU_HWPT_INVALIDATE) * @size: sizeof(struct iommu_hwpt_invalidate) - * @hwpt_id: ID of a nested HWPT for cache invalidation + * @hwpt_id: ID of a nested HWPT or a vIOMMU, for cache invalidation * @data_uptr: User pointer to an array of driver-specific cache invalidation * data. * @data_type: One of enum iommu_hwpt_invalidate_data_type, defining the data @@ -711,8 +711,11 @@ struct iommu_hwpt_vtd_s1_invalidate { * Output the number of requests successfully handled by kernel. * @__reserved: Must be 0. * - * Invalidate the iommu cache for user-managed page table. Modifications on a - * user-managed page table should be followed by this operation to sync cache. + * Invalidate iommu cache for user-managed page table or vIOMMU. Modifications + * on a user-managed page table should be followed by this operation, if a HWPT + * is passed in via @hwpt_id. Other caches, such as device cache or descriptor + * cache can be flushed if a vIOMMU is passed in via the @hwpt_id field. + * * Each ioctl can support one or more cache invalidation requests in the array * that has a total size of @entry_len * @entry_num. * -- cgit v1.2.3