1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_TIME64_H 3 #define _LINUX_TIME64_H 4 5 #include <linux/math64.h> 6 7 typedef __s64 time64_t; 8 typedef __u64 timeu64_t; 9 10 #include <uapi/linux/time.h> 11 12 struct timespec64 { 13 time64_t tv_sec; /* seconds */ 14 long tv_nsec; /* nanoseconds */ 15 }; 16 17 struct itimerspec64 { 18 struct timespec64 it_interval; 19 struct timespec64 it_value; 20 }; 21 22 /* Parameters used to convert the timespec values: */ 23 #define MSEC_PER_SEC 1000L 24 #define USEC_PER_MSEC 1000L 25 #define NSEC_PER_USEC 1000L 26 #define NSEC_PER_MSEC 1000000L 27 #define USEC_PER_SEC 1000000L 28 #define NSEC_PER_SEC 1000000000L 29 #define FSEC_PER_SEC 1000000000000000LL 30 31 /* Located here for timespec[64]_valid_strict */ 32 #define TIME64_MAX ((s64)~((u64)1 << 63)) 33 #define TIME64_MIN (-TIME64_MAX - 1) 34 35 #define KTIME_MAX ((s64)~((u64)1 << 63)) 36 #define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC) 37 38 /* 39 * Limits for settimeofday(): 40 * 41 * To prevent setting the time close to the wraparound point time setting 42 * is limited so a reasonable uptime can be accomodated. Uptime of 30 years 43 * should be really sufficient, which means the cutoff is 2232. At that 44 * point the cutoff is just a small part of the larger problem. 45 */ 46 #define TIME_UPTIME_SEC_MAX (30LL * 365 * 24 *3600) 47 #define TIME_SETTOD_SEC_MAX (KTIME_SEC_MAX - TIME_UPTIME_SEC_MAX) 48 49 static inline int timespec64_equal(const struct timespec64 *a, 50 const struct timespec64 *b) 51 { 52 return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec); 53 } 54 55 /* 56 * lhs < rhs: return <0 57 * lhs == rhs: return 0 58 * lhs > rhs: return >0 59 */ 60 static inline int timespec64_compare(const struct timespec64 *lhs, const struct timespec64 *rhs) 61 { 62 if (lhs->tv_sec < rhs->tv_sec) 63 return -1; 64 if (lhs->tv_sec > rhs->tv_sec) 65 return 1; 66 return lhs->tv_nsec - rhs->tv_nsec; 67 } 68 69 extern void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec); 70 71 static inline struct timespec64 timespec64_add(struct timespec64 lhs, 72 struct timespec64 rhs) 73 { 74 struct timespec64 ts_delta; 75 set_normalized_timespec64(&ts_delta, lhs.tv_sec + rhs.tv_sec, 76 lhs.tv_nsec + rhs.tv_nsec); 77 return ts_delta; 78 } 79 80 /* 81 * sub = lhs - rhs, in normalized form 82 */ 83 static inline struct timespec64 timespec64_sub(struct timespec64 lhs, 84 struct timespec64 rhs) 85 { 86 struct timespec64 ts_delta; 87 set_normalized_timespec64(&ts_delta, lhs.tv_sec - rhs.tv_sec, 88 lhs.tv_nsec - rhs.tv_nsec); 89 return ts_delta; 90 } 91 92 /* 93 * Returns true if the timespec64 is norm, false if denorm: 94 */ 95 static inline bool timespec64_valid(const struct timespec64 *ts) 96 { 97 /* Dates before 1970 are bogus */ 98 if (ts->tv_sec < 0) 99 return false; 100 /* Can't have more nanoseconds then a second */ 101 if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) 102 return false; 103 return true; 104 } 105 106 static inline bool timespec64_valid_strict(const struct timespec64 *ts) 107 { 108 if (!timespec64_valid(ts)) 109 return false; 110 /* Disallow values that could overflow ktime_t */ 111 if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX) 112 return false; 113 return true; 114 } 115 116 static inline bool timespec64_valid_settod(const struct timespec64 *ts) 117 { 118 if (!timespec64_valid(ts)) 119 return false; 120 /* Disallow values which cause overflow issues vs. CLOCK_REALTIME */ 121 if ((unsigned long long)ts->tv_sec >= TIME_SETTOD_SEC_MAX) 122 return false; 123 return true; 124 } 125 126 /** 127 * timespec64_to_ns - Convert timespec64 to nanoseconds 128 * @ts: pointer to the timespec64 variable to be converted 129 * 130 * Returns the scalar nanosecond representation of the timespec64 131 * parameter. 132 */ 133 static inline s64 timespec64_to_ns(const struct timespec64 *ts) 134 { 135 return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec; 136 } 137 138 /** 139 * ns_to_timespec64 - Convert nanoseconds to timespec64 140 * @nsec: the nanoseconds value to be converted 141 * 142 * Returns the timespec64 representation of the nsec parameter. 143 */ 144 extern struct timespec64 ns_to_timespec64(const s64 nsec); 145 146 /** 147 * timespec64_add_ns - Adds nanoseconds to a timespec64 148 * @a: pointer to timespec64 to be incremented 149 * @ns: unsigned nanoseconds value to be added 150 * 151 * This must always be inlined because its used from the x86-64 vdso, 152 * which cannot call other kernel functions. 153 */ 154 static __always_inline void timespec64_add_ns(struct timespec64 *a, u64 ns) 155 { 156 a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns); 157 a->tv_nsec = ns; 158 } 159 160 /* 161 * timespec64_add_safe assumes both values are positive and checks for 162 * overflow. It will return TIME64_MAX in case of overflow. 163 */ 164 extern struct timespec64 timespec64_add_safe(const struct timespec64 lhs, 165 const struct timespec64 rhs); 166 167 #endif /* _LINUX_TIME64_H */ 168