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