1 #ifndef _LINUX_TIME_H
2 #define _LINUX_TIME_H
3
4 #include <linux/types.h>
5
6 #ifdef __KERNEL__
7 # include <linux/cache.h>
8 # include <linux/seqlock.h>
9 # include <linux/math64.h>
10 #endif
11
12 #ifndef _STRUCT_TIMESPEC
13 #define _STRUCT_TIMESPEC
14 struct timespec {
15 __kernel_time_t tv_sec; /* seconds */
16 long tv_nsec; /* nanoseconds */
17 };
18 #endif
19
20 struct timeval {
21 __kernel_time_t tv_sec; /* seconds */
22 __kernel_suseconds_t tv_usec; /* microseconds */
23 };
24
25 struct timezone {
26 int tz_minuteswest; /* minutes west of Greenwich */
27 int tz_dsttime; /* type of dst correction */
28 };
29
30 #ifdef __KERNEL__
31
32 extern struct timezone sys_tz;
33
34 /* Parameters used to convert the timespec values: */
35 #define MSEC_PER_SEC 1000L
36 #define USEC_PER_MSEC 1000L
37 #define NSEC_PER_USEC 1000L
38 #define NSEC_PER_MSEC 1000000L
39 #define USEC_PER_SEC 1000000L
40 #define NSEC_PER_SEC 1000000000L
41 #define FSEC_PER_SEC 1000000000000000LL
42
43 #define TIME_T_MAX (time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1)
44
timespec_equal(const struct timespec * a,const struct timespec * b)45 static inline int timespec_equal(const struct timespec *a,
46 const struct timespec *b)
47 {
48 return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
49 }
50
51 /*
52 * lhs < rhs: return <0
53 * lhs == rhs: return 0
54 * lhs > rhs: return >0
55 */
timespec_compare(const struct timespec * lhs,const struct timespec * rhs)56 static inline int timespec_compare(const struct timespec *lhs, const struct timespec *rhs)
57 {
58 if (lhs->tv_sec < rhs->tv_sec)
59 return -1;
60 if (lhs->tv_sec > rhs->tv_sec)
61 return 1;
62 return lhs->tv_nsec - rhs->tv_nsec;
63 }
64
timeval_compare(const struct timeval * lhs,const struct timeval * rhs)65 static inline int timeval_compare(const struct timeval *lhs, const struct timeval *rhs)
66 {
67 if (lhs->tv_sec < rhs->tv_sec)
68 return -1;
69 if (lhs->tv_sec > rhs->tv_sec)
70 return 1;
71 return lhs->tv_usec - rhs->tv_usec;
72 }
73
74 extern unsigned long mktime(const unsigned int year, const unsigned int mon,
75 const unsigned int day, const unsigned int hour,
76 const unsigned int min, const unsigned int sec);
77
78 extern void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec);
79
80 /*
81 * timespec_add_safe assumes both values are positive and checks
82 * for overflow. It will return TIME_T_MAX if the reutrn would be
83 * smaller then either of the arguments.
84 */
85 extern struct timespec timespec_add_safe(const struct timespec lhs,
86 const struct timespec rhs);
87
88
timespec_add(struct timespec lhs,struct timespec rhs)89 static inline struct timespec timespec_add(struct timespec lhs,
90 struct timespec rhs)
91 {
92 struct timespec ts_delta;
93 set_normalized_timespec(&ts_delta, lhs.tv_sec + rhs.tv_sec,
94 lhs.tv_nsec + rhs.tv_nsec);
95 return ts_delta;
96 }
97
98 /*
99 * sub = lhs - rhs, in normalized form
100 */
timespec_sub(struct timespec lhs,struct timespec rhs)101 static inline struct timespec timespec_sub(struct timespec lhs,
102 struct timespec rhs)
103 {
104 struct timespec ts_delta;
105 set_normalized_timespec(&ts_delta, lhs.tv_sec - rhs.tv_sec,
106 lhs.tv_nsec - rhs.tv_nsec);
107 return ts_delta;
108 }
109
110 #define KTIME_MAX ((s64)~((u64)1 << 63))
111 #if (BITS_PER_LONG == 64)
112 # define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC)
113 #else
114 # define KTIME_SEC_MAX LONG_MAX
115 #endif
116
117 /*
118 * Returns true if the timespec is norm, false if denorm:
119 */
timespec_valid(const struct timespec * ts)120 static inline bool timespec_valid(const struct timespec *ts)
121 {
122 /* Dates before 1970 are bogus */
123 if (ts->tv_sec < 0)
124 return false;
125 /* Can't have more nanoseconds then a second */
126 if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
127 return false;
128 return true;
129 }
130
timespec_valid_strict(const struct timespec * ts)131 static inline bool timespec_valid_strict(const struct timespec *ts)
132 {
133 if (!timespec_valid(ts))
134 return false;
135 /* Disallow values that could overflow ktime_t */
136 if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
137 return false;
138 return true;
139 }
140
141 extern void read_persistent_clock(struct timespec *ts);
142 extern void read_boot_clock(struct timespec *ts);
143 extern int update_persistent_clock(struct timespec now);
144 void timekeeping_init(void);
145 extern int timekeeping_suspended;
146
147 unsigned long get_seconds(void);
148 struct timespec current_kernel_time(void);
149 struct timespec __current_kernel_time(void); /* does not take xtime_lock */
150 struct timespec get_monotonic_coarse(void);
151 void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
152 struct timespec *wtom, struct timespec *sleep);
153 void timekeeping_inject_sleeptime(struct timespec *delta);
154
155 #define CURRENT_TIME (current_kernel_time())
156 #define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 })
157
158 /* Some architectures do not supply their own clocksource.
159 * This is mainly the case in architectures that get their
160 * inter-tick times by reading the counter on their interval
161 * timer. Since these timers wrap every tick, they're not really
162 * useful as clocksources. Wrapping them to act like one is possible
163 * but not very efficient. So we provide a callout these arches
164 * can implement for use with the jiffies clocksource to provide
165 * finer then tick granular time.
166 */
167 #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
168 extern u32 arch_gettimeoffset(void);
169 #else
arch_gettimeoffset(void)170 static inline u32 arch_gettimeoffset(void) { return 0; }
171 #endif
172
173 extern void do_gettimeofday(struct timeval *tv);
174 extern int do_settimeofday(const struct timespec *tv);
175 extern int do_sys_settimeofday(const struct timespec *tv,
176 const struct timezone *tz);
177 #define do_posix_clock_monotonic_gettime(ts) ktime_get_ts(ts)
178 extern long do_utimes(int dfd, const char __user *filename, struct timespec *times, int flags);
179 struct itimerval;
180 extern int do_setitimer(int which, struct itimerval *value,
181 struct itimerval *ovalue);
182 extern unsigned int alarm_setitimer(unsigned int seconds);
183 extern int do_getitimer(int which, struct itimerval *value);
184 extern void getnstimeofday(struct timespec *tv);
185 extern void getrawmonotonic(struct timespec *ts);
186 extern void getnstime_raw_and_real(struct timespec *ts_raw,
187 struct timespec *ts_real);
188 extern void getboottime(struct timespec *ts);
189 extern void monotonic_to_bootbased(struct timespec *ts);
190 extern void get_monotonic_boottime(struct timespec *ts);
191
192 extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
193 extern int timekeeping_valid_for_hres(void);
194 extern u64 timekeeping_max_deferment(void);
195 extern void timekeeping_leap_insert(int leapsecond);
196 extern int timekeeping_inject_offset(struct timespec *ts);
197
198 struct tms;
199 extern void do_sys_times(struct tms *);
200
201 /*
202 * Similar to the struct tm in userspace <time.h>, but it needs to be here so
203 * that the kernel source is self contained.
204 */
205 struct tm {
206 /*
207 * the number of seconds after the minute, normally in the range
208 * 0 to 59, but can be up to 60 to allow for leap seconds
209 */
210 int tm_sec;
211 /* the number of minutes after the hour, in the range 0 to 59*/
212 int tm_min;
213 /* the number of hours past midnight, in the range 0 to 23 */
214 int tm_hour;
215 /* the day of the month, in the range 1 to 31 */
216 int tm_mday;
217 /* the number of months since January, in the range 0 to 11 */
218 int tm_mon;
219 /* the number of years since 1900 */
220 long tm_year;
221 /* the number of days since Sunday, in the range 0 to 6 */
222 int tm_wday;
223 /* the number of days since January 1, in the range 0 to 365 */
224 int tm_yday;
225 };
226
227 void time_to_tm(time_t totalsecs, int offset, struct tm *result);
228
229 /**
230 * timespec_to_ns - Convert timespec to nanoseconds
231 * @ts: pointer to the timespec variable to be converted
232 *
233 * Returns the scalar nanosecond representation of the timespec
234 * parameter.
235 */
timespec_to_ns(const struct timespec * ts)236 static inline s64 timespec_to_ns(const struct timespec *ts)
237 {
238 return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
239 }
240
241 /**
242 * timeval_to_ns - Convert timeval to nanoseconds
243 * @ts: pointer to the timeval variable to be converted
244 *
245 * Returns the scalar nanosecond representation of the timeval
246 * parameter.
247 */
timeval_to_ns(const struct timeval * tv)248 static inline s64 timeval_to_ns(const struct timeval *tv)
249 {
250 return ((s64) tv->tv_sec * NSEC_PER_SEC) +
251 tv->tv_usec * NSEC_PER_USEC;
252 }
253
254 /**
255 * ns_to_timespec - Convert nanoseconds to timespec
256 * @nsec: the nanoseconds value to be converted
257 *
258 * Returns the timespec representation of the nsec parameter.
259 */
260 extern struct timespec ns_to_timespec(const s64 nsec);
261
262 /**
263 * ns_to_timeval - Convert nanoseconds to timeval
264 * @nsec: the nanoseconds value to be converted
265 *
266 * Returns the timeval representation of the nsec parameter.
267 */
268 extern struct timeval ns_to_timeval(const s64 nsec);
269
270 /**
271 * timespec_add_ns - Adds nanoseconds to a timespec
272 * @a: pointer to timespec to be incremented
273 * @ns: unsigned nanoseconds value to be added
274 *
275 * This must always be inlined because its used from the x86-64 vdso,
276 * which cannot call other kernel functions.
277 */
timespec_add_ns(struct timespec * a,u64 ns)278 static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
279 {
280 a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
281 a->tv_nsec = ns;
282 }
283
284 #endif /* __KERNEL__ */
285
286 /*
287 * Names of the interval timers, and structure
288 * defining a timer setting:
289 */
290 #define ITIMER_REAL 0
291 #define ITIMER_VIRTUAL 1
292 #define ITIMER_PROF 2
293
294 struct itimerspec {
295 struct timespec it_interval; /* timer period */
296 struct timespec it_value; /* timer expiration */
297 };
298
299 struct itimerval {
300 struct timeval it_interval; /* timer interval */
301 struct timeval it_value; /* current value */
302 };
303
304 /*
305 * The IDs of the various system clocks (for POSIX.1b interval timers):
306 */
307 #define CLOCK_REALTIME 0
308 #define CLOCK_MONOTONIC 1
309 #define CLOCK_PROCESS_CPUTIME_ID 2
310 #define CLOCK_THREAD_CPUTIME_ID 3
311 #define CLOCK_MONOTONIC_RAW 4
312 #define CLOCK_REALTIME_COARSE 5
313 #define CLOCK_MONOTONIC_COARSE 6
314 #define CLOCK_BOOTTIME 7
315 #define CLOCK_REALTIME_ALARM 8
316 #define CLOCK_BOOTTIME_ALARM 9
317
318 /*
319 * The IDs of various hardware clocks:
320 */
321 #define CLOCK_SGI_CYCLE 10
322 #define MAX_CLOCKS 16
323 #define CLOCKS_MASK (CLOCK_REALTIME | CLOCK_MONOTONIC)
324 #define CLOCKS_MONO CLOCK_MONOTONIC
325
326 /*
327 * The various flags for setting POSIX.1b interval timers:
328 */
329 #define TIMER_ABSTIME 0x01
330
331 #endif
332