1#ifndef _LINUX_TIME_H
2#define _LINUX_TIME_H
3
4# include <linux/cache.h>
5# include <linux/seqlock.h>
6# include <linux/math64.h>
7# include <linux/time64.h>
8
9extern struct timezone sys_tz;
10
11#define TIME_T_MAX	(time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1)
12
13static inline int timespec_equal(const struct timespec *a,
14                                 const struct timespec *b)
15{
16	return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
17}
18
19/*
20 * lhs < rhs:  return <0
21 * lhs == rhs: return 0
22 * lhs > rhs:  return >0
23 */
24static inline int timespec_compare(const struct timespec *lhs, const struct timespec *rhs)
25{
26	if (lhs->tv_sec < rhs->tv_sec)
27		return -1;
28	if (lhs->tv_sec > rhs->tv_sec)
29		return 1;
30	return lhs->tv_nsec - rhs->tv_nsec;
31}
32
33static inline int timeval_compare(const struct timeval *lhs, const struct timeval *rhs)
34{
35	if (lhs->tv_sec < rhs->tv_sec)
36		return -1;
37	if (lhs->tv_sec > rhs->tv_sec)
38		return 1;
39	return lhs->tv_usec - rhs->tv_usec;
40}
41
42extern time64_t mktime64(const unsigned int year, const unsigned int mon,
43			const unsigned int day, const unsigned int hour,
44			const unsigned int min, const unsigned int sec);
45
46/**
47 * Deprecated. Use mktime64().
48 */
49static inline unsigned long mktime(const unsigned int year,
50			const unsigned int mon, const unsigned int day,
51			const unsigned int hour, const unsigned int min,
52			const unsigned int sec)
53{
54	return mktime64(year, mon, day, hour, min, sec);
55}
56
57extern void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec);
58
59/*
60 * timespec_add_safe assumes both values are positive and checks
61 * for overflow. It will return TIME_T_MAX if the reutrn would be
62 * smaller then either of the arguments.
63 */
64extern struct timespec timespec_add_safe(const struct timespec lhs,
65					 const struct timespec rhs);
66
67
68static inline struct timespec timespec_add(struct timespec lhs,
69						struct timespec rhs)
70{
71	struct timespec ts_delta;
72	set_normalized_timespec(&ts_delta, lhs.tv_sec + rhs.tv_sec,
73				lhs.tv_nsec + rhs.tv_nsec);
74	return ts_delta;
75}
76
77/*
78 * sub = lhs - rhs, in normalized form
79 */
80static inline struct timespec timespec_sub(struct timespec lhs,
81						struct timespec rhs)
82{
83	struct timespec ts_delta;
84	set_normalized_timespec(&ts_delta, lhs.tv_sec - rhs.tv_sec,
85				lhs.tv_nsec - rhs.tv_nsec);
86	return ts_delta;
87}
88
89/*
90 * Returns true if the timespec is norm, false if denorm:
91 */
92static inline bool timespec_valid(const struct timespec *ts)
93{
94	/* Dates before 1970 are bogus */
95	if (ts->tv_sec < 0)
96		return false;
97	/* Can't have more nanoseconds then a second */
98	if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
99		return false;
100	return true;
101}
102
103static inline bool timespec_valid_strict(const struct timespec *ts)
104{
105	if (!timespec_valid(ts))
106		return false;
107	/* Disallow values that could overflow ktime_t */
108	if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
109		return false;
110	return true;
111}
112
113static inline bool timeval_valid(const struct timeval *tv)
114{
115	/* Dates before 1970 are bogus */
116	if (tv->tv_sec < 0)
117		return false;
118
119	/* Can't have more microseconds then a second */
120	if (tv->tv_usec < 0 || tv->tv_usec >= USEC_PER_SEC)
121		return false;
122
123	return true;
124}
125
126extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
127
128#define CURRENT_TIME		(current_kernel_time())
129#define CURRENT_TIME_SEC	((struct timespec) { get_seconds(), 0 })
130
131/* Some architectures do not supply their own clocksource.
132 * This is mainly the case in architectures that get their
133 * inter-tick times by reading the counter on their interval
134 * timer. Since these timers wrap every tick, they're not really
135 * useful as clocksources. Wrapping them to act like one is possible
136 * but not very efficient. So we provide a callout these arches
137 * can implement for use with the jiffies clocksource to provide
138 * finer then tick granular time.
139 */
140#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
141extern u32 (*arch_gettimeoffset)(void);
142#endif
143
144struct itimerval;
145extern int do_setitimer(int which, struct itimerval *value,
146			struct itimerval *ovalue);
147extern int do_getitimer(int which, struct itimerval *value);
148
149extern unsigned int alarm_setitimer(unsigned int seconds);
150
151extern long do_utimes(int dfd, const char __user *filename, struct timespec *times, int flags);
152
153struct tms;
154extern void do_sys_times(struct tms *);
155
156/*
157 * Similar to the struct tm in userspace <time.h>, but it needs to be here so
158 * that the kernel source is self contained.
159 */
160struct tm {
161	/*
162	 * the number of seconds after the minute, normally in the range
163	 * 0 to 59, but can be up to 60 to allow for leap seconds
164	 */
165	int tm_sec;
166	/* the number of minutes after the hour, in the range 0 to 59*/
167	int tm_min;
168	/* the number of hours past midnight, in the range 0 to 23 */
169	int tm_hour;
170	/* the day of the month, in the range 1 to 31 */
171	int tm_mday;
172	/* the number of months since January, in the range 0 to 11 */
173	int tm_mon;
174	/* the number of years since 1900 */
175	long tm_year;
176	/* the number of days since Sunday, in the range 0 to 6 */
177	int tm_wday;
178	/* the number of days since January 1, in the range 0 to 365 */
179	int tm_yday;
180};
181
182void time_to_tm(time_t totalsecs, int offset, struct tm *result);
183
184/**
185 * timespec_to_ns - Convert timespec to nanoseconds
186 * @ts:		pointer to the timespec variable to be converted
187 *
188 * Returns the scalar nanosecond representation of the timespec
189 * parameter.
190 */
191static inline s64 timespec_to_ns(const struct timespec *ts)
192{
193	return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
194}
195
196/**
197 * timeval_to_ns - Convert timeval to nanoseconds
198 * @ts:		pointer to the timeval variable to be converted
199 *
200 * Returns the scalar nanosecond representation of the timeval
201 * parameter.
202 */
203static inline s64 timeval_to_ns(const struct timeval *tv)
204{
205	return ((s64) tv->tv_sec * NSEC_PER_SEC) +
206		tv->tv_usec * NSEC_PER_USEC;
207}
208
209/**
210 * ns_to_timespec - Convert nanoseconds to timespec
211 * @nsec:	the nanoseconds value to be converted
212 *
213 * Returns the timespec representation of the nsec parameter.
214 */
215extern struct timespec ns_to_timespec(const s64 nsec);
216
217/**
218 * ns_to_timeval - Convert nanoseconds to timeval
219 * @nsec:	the nanoseconds value to be converted
220 *
221 * Returns the timeval representation of the nsec parameter.
222 */
223extern struct timeval ns_to_timeval(const s64 nsec);
224
225/**
226 * timespec_add_ns - Adds nanoseconds to a timespec
227 * @a:		pointer to timespec to be incremented
228 * @ns:		unsigned nanoseconds value to be added
229 *
230 * This must always be inlined because its used from the x86-64 vdso,
231 * which cannot call other kernel functions.
232 */
233static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
234{
235	a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
236	a->tv_nsec = ns;
237}
238
239#endif
240