1 /* 2 * Copyright (c) 2017 Apple Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 #ifndef _COMMPAGE_H 29 #define _COMMPAGE_H 30 31 #ifdef PRIVATE 32 33 #include <stdint.h> 34 35 #define _COMM_PAGE32_SIGNATURE_STRING "commpage 32-bit" 36 #define _COMM_PAGE64_SIGNATURE_STRING "commpage 64-bit" 37 38 typedef volatile struct commpage_timeofday_data { 39 uint64_t TimeStamp_tick; 40 uint64_t TimeStamp_sec; 41 uint64_t TimeStamp_frac; 42 uint64_t Ticks_scale; 43 uint64_t Ticks_per_sec; 44 } new_commpage_timeofday_data_t; 45 46 /*! 47 * @macro COMM_PAGE_SLOT_TYPE 48 * 49 * @brief 50 * Macro that expands to the proper type for a pointer to a commpage slot, 51 * to be used in a local variable declaration. 52 * 53 * @description 54 * Usage is something like: 55 * <code> 56 * COMM_PAGE_SLOT_TYPE(uint64_t) slot = COMM_PAGE_SLOT(uint64_t, FOO); 57 * </code> 58 * 59 * @param type The scalar base type for the slot. 60 */ 61 #if __has_feature(address_sanitizer) 62 #define COMM_PAGE_SLOT_TYPE(type_t) type_t __attribute__((address_space(1))) volatile * 63 #else 64 #define COMM_PAGE_SLOT_TYPE(type_t) type_t volatile * 65 #endif 66 67 /*! 68 * @macro COMM_PAGE_SLOT 69 * 70 * @brief 71 * Macro that expands to the properly typed address for a commpage slot. 72 * 73 * @param type The scalar base type for the slot. 74 * @param name The slot name, without its @c _COMM_PAGE_ prefix. 75 */ 76 #define COMM_PAGE_SLOT(type_t, name) ((COMM_PAGE_SLOT_TYPE(type_t))_COMM_PAGE_##name) 77 78 /*! 79 * @macro COMM_PAGE_READ 80 * 81 * @brief 82 * Performs a single read from the commpage in a way that doesn't trip 83 * address sanitizers. 84 * 85 * @description 86 * Typical use looks like this: 87 * <code> 88 * uint64_t foo_value = COMM_PAGE_READ(uint64_t, FOO); 89 * </code> 90 * 91 * @param type The scalar base type for the slot. 92 * @param name The slot name, without its @c _COMM_PAGE_ prefix. 93 */ 94 #define COMM_PAGE_READ(type_t, slot) (*(COMM_PAGE_SLOT(type_t, slot))) 95 96 #endif 97 98 #endif 99