From: Nicolin Chen nicolinc@nvidia.com
Wrap up the data pointer/num sanity and __iommu_copy_struct_from_user call for iommu drivers to copy driver specific data at a specific location in the struct iommu_user_data_array, and iommu_respond_struct_to_user_array() to copy response to a specific location in the struct iommu_user_data_array.
And expect it to be used in cache_invalidate_user ops for example.
Signed-off-by: Nicolin Chen nicolinc@nvidia.com Co-developed-by: Yi Liu yi.l.liu@intel.com Signed-off-by: Yi Liu yi.l.liu@intel.com --- include/linux/iommu.h | 74 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+)
diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 5c4a17f13761..cfab934e71a2 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -342,6 +342,80 @@ static inline int __iommu_copy_struct_from_user( sizeof(*kdst), \ offsetofend(typeof(*kdst), min_last))
+/** + * __iommu_copy_struct_from_user_array - Copy iommu driver specific user space + * data from an iommu_user_data_array + * @dst_data: Pointer to an iommu driver specific user data that is defined in + * include/uapi/linux/iommufd.h + * @src_array: Pointer to a struct iommu_user_data_array for a user space array + * @data_type: The data type of the @dst_data. Must match with @src_array.type + * @index: Index to the location in the array to copy user data from + * @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_struct_from_user_array(void *dst_data, + const struct iommu_user_data_array *src_array, + unsigned int data_type, unsigned int index, + size_t data_len, size_t min_len) +{ + struct iommu_user_data src_data; + + if (WARN_ON(!src_array || index >= src_array->entry_num)) + return -EINVAL; + if (!src_array->entry_num) + return -EINVAL; + src_data.uptr = src_array->uptr + src_array->entry_len * index; + src_data.len = src_array->entry_len; + src_data.type = src_array->type; + + return __iommu_copy_struct_from_user(dst_data, &src_data, data_type, + data_len, min_len); +} + +/** + * iommu_copy_struct_from_user_array - Copy iommu driver specific user space + * data from an iommu_user_data_array + * @kdst: Pointer to an iommu driver specific user data that is defined in + * include/uapi/linux/iommufd.h + * @user_array: Pointer to a struct iommu_user_data_array for a user space + * array + * @data_type: The data type of the @kdst. Must match with @user_array->type + * @index: Index to the location in the array to copy user data from + * @min_last: The last memember of the data structure @kdst points in the + * initial version. + * Return 0 for success, otherwise -error. + */ +#define iommu_copy_struct_from_user_array(kdst, user_array, data_type, \ + index, min_last) \ + __iommu_copy_struct_from_user_array(kdst, user_array, data_type, \ + index, sizeof(*kdst), \ + offsetofend(typeof(*kdst), \ + min_last)) + +/** + * iommu_respond_struct_to_user_array - Copy the response in @ksrc back to + * a specific entry of user array + * @user_array: Pointer to a struct iommu_user_data_array for a user space + * array + * @index: Index to the location in the array to copy response + * @ksrc: Pointer to kernel structure + * @klen: Length of @ksrc struct + * + * This only copies response of one entry (@index) in @user_array. + */ +static inline int +iommu_respond_struct_to_user_array(const struct iommu_user_data_array *array, + unsigned int index, void *ksrc, size_t klen) +{ + if (copy_to_user(array->uptr + array->entry_len * index, + ksrc, min_t(size_t, array->entry_len, klen))) + return -EFAULT; + return 0; +} + /** * struct iommu_ops - iommu ops and capabilities * @capable: check capability