From: Lu Baolu <[email protected]> The updates of the PTEs in the nested page table will be propagated to the hardware caches on both IOMMU (IOTLB) and devices (DevTLB/ATC).
Add a new domain op cache_invalidate_user for the userspace to flush the hardware caches for a nested domain through iommufd. No wrapper for it, as it's only supposed to be used by iommufd. Then, pass in invalidation requests in form of a user data array conatining a number of invalidation data entries. Signed-off-by: Lu Baolu <[email protected]> Reviewed-by: Kevin Tian <[email protected]> Signed-off-by: Nicolin Chen <[email protected]> Signed-off-by: Yi Liu <[email protected]> --- include/linux/iommu.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/include/linux/iommu.h b/include/linux/iommu.h index ec289c1016f5..0c1ff7fe4fa1 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -284,6 +284,24 @@ struct iommu_user_data { size_t len; }; +/** + * struct iommu_user_data_array - iommu driver specific user space data array + * @type: The data type of all the entries in the user buffer array + * @uptr: Pointer to the user buffer array for copy_from_user() + * @entry_len: The fixed-width length of a entry in the array, in bytes + * @entry_num: The number of total entries in the array + * + * A array having a @entry_num number of @entry_len sized entries, each entry is + * user space data, an uAPI defined in include/uapi/linux/iommufd.h where @type + * is also defined as enum iommu_xyz_data_type. + */ +struct iommu_user_data_array { + unsigned int type; + void __user *uptr; + size_t entry_len; + int entry_num; +}; + /** * __iommu_copy_struct_from_user - Copy iommu driver specific user space data * @dst_data: Pointer to an iommu driver specific user data that is defined in @@ -440,6 +458,15 @@ struct iommu_ops { * @iotlb_sync_map: Sync mappings created recently using @map to the hardware * @iotlb_sync: Flush all queued ranges from the hardware TLBs and empty flush * queue + * @cache_invalidate_user: Flush hardware cache for user space IO page table. + * The @domain must be IOMMU_DOMAIN_NESTED. The @array + * passes in the cache invalidation requests, in form + * of a driver data structure. The driver must update + * array->entry_num to report the number of handled + * invalidation requests. The 32-bit @error_code can + * forward a driver specific error code to user space. + * Both the driver data structure and the error code + * must be defined in include/uapi/linux/iommufd.h * @iova_to_phys: translate iova to physical address * @enforce_cache_coherency: Prevent any kind of DMA from bypassing IOMMU_CACHE, * including no-snoop TLPs on PCIe or other platform @@ -465,6 +492,9 @@ struct iommu_domain_ops { size_t size); void (*iotlb_sync)(struct iommu_domain *domain, struct iommu_iotlb_gather *iotlb_gather); + int (*cache_invalidate_user)(struct iommu_domain *domain, + struct iommu_user_data_array *array, + u32 *error_code); phys_addr_t (*iova_to_phys)(struct iommu_domain *domain, dma_addr_t iova); -- 2.34.1
