Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_TIME64_H
3#define _LINUX_TIME64_H
4
5#include <linux/math64.h>
6
7typedef __s64 time64_t;
8typedef __u64 timeu64_t;
9
10/* CONFIG_64BIT_TIME enables new 64 bit time_t syscalls in the compat path
11 * and 32-bit emulation.
12 */
13#ifndef CONFIG_64BIT_TIME
14#define __kernel_timespec timespec
15#endif
16
17#include <uapi/linux/time.h>
18
19struct timespec64 {
20 time64_t tv_sec; /* seconds */
21 long tv_nsec; /* nanoseconds */
22};
23
24struct itimerspec64 {
25 struct timespec64 it_interval;
26 struct timespec64 it_value;
27};
28
29/* Parameters used to convert the timespec values: */
30#define MSEC_PER_SEC 1000L
31#define USEC_PER_MSEC 1000L
32#define NSEC_PER_USEC 1000L
33#define NSEC_PER_MSEC 1000000L
34#define USEC_PER_SEC 1000000L
35#define NSEC_PER_SEC 1000000000L
36#define FSEC_PER_SEC 1000000000000000LL
37
38/* Located here for timespec[64]_valid_strict */
39#define TIME64_MAX ((s64)~((u64)1 << 63))
40#define KTIME_MAX ((s64)~((u64)1 << 63))
41#define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC)
42
43static inline int timespec64_equal(const struct timespec64 *a,
44 const struct timespec64 *b)
45{
46 return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
47}
48
49/*
50 * lhs < rhs: return <0
51 * lhs == rhs: return 0
52 * lhs > rhs: return >0
53 */
54static inline int timespec64_compare(const struct timespec64 *lhs, const struct timespec64 *rhs)
55{
56 if (lhs->tv_sec < rhs->tv_sec)
57 return -1;
58 if (lhs->tv_sec > rhs->tv_sec)
59 return 1;
60 return lhs->tv_nsec - rhs->tv_nsec;
61}
62
63extern void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec);
64
65static inline struct timespec64 timespec64_add(struct timespec64 lhs,
66 struct timespec64 rhs)
67{
68 struct timespec64 ts_delta;
69 set_normalized_timespec64(&ts_delta, lhs.tv_sec + rhs.tv_sec,
70 lhs.tv_nsec + rhs.tv_nsec);
71 return ts_delta;
72}
73
74/*
75 * sub = lhs - rhs, in normalized form
76 */
77static inline struct timespec64 timespec64_sub(struct timespec64 lhs,
78 struct timespec64 rhs)
79{
80 struct timespec64 ts_delta;
81 set_normalized_timespec64(&ts_delta, lhs.tv_sec - rhs.tv_sec,
82 lhs.tv_nsec - rhs.tv_nsec);
83 return ts_delta;
84}
85
86/*
87 * Returns true if the timespec64 is norm, false if denorm:
88 */
89static inline bool timespec64_valid(const struct timespec64 *ts)
90{
91 /* Dates before 1970 are bogus */
92 if (ts->tv_sec < 0)
93 return false;
94 /* Can't have more nanoseconds then a second */
95 if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
96 return false;
97 return true;
98}
99
100static inline bool timespec64_valid_strict(const struct timespec64 *ts)
101{
102 if (!timespec64_valid(ts))
103 return false;
104 /* Disallow values that could overflow ktime_t */
105 if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
106 return false;
107 return true;
108}
109
110/**
111 * timespec64_to_ns - Convert timespec64 to nanoseconds
112 * @ts: pointer to the timespec64 variable to be converted
113 *
114 * Returns the scalar nanosecond representation of the timespec64
115 * parameter.
116 */
117static inline s64 timespec64_to_ns(const struct timespec64 *ts)
118{
119 return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
120}
121
122/**
123 * ns_to_timespec64 - Convert nanoseconds to timespec64
124 * @nsec: the nanoseconds value to be converted
125 *
126 * Returns the timespec64 representation of the nsec parameter.
127 */
128extern struct timespec64 ns_to_timespec64(const s64 nsec);
129
130/**
131 * timespec64_add_ns - Adds nanoseconds to a timespec64
132 * @a: pointer to timespec64 to be incremented
133 * @ns: unsigned nanoseconds value to be added
134 *
135 * This must always be inlined because its used from the x86-64 vdso,
136 * which cannot call other kernel functions.
137 */
138static __always_inline void timespec64_add_ns(struct timespec64 *a, u64 ns)
139{
140 a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
141 a->tv_nsec = ns;
142}
143
144/*
145 * timespec64_add_safe assumes both values are positive and checks for
146 * overflow. It will return TIME64_MAX in case of overflow.
147 */
148extern struct timespec64 timespec64_add_safe(const struct timespec64 lhs,
149 const struct timespec64 rhs);
150
151#endif /* _LINUX_TIME64_H */