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 <uapi/linux/time.h>
8
9 extern struct timezone sys_tz;
10
11 /* Parameters used to convert the timespec values: */
12 #define MSEC_PER_SEC 1000L
13 #define USEC_PER_MSEC 1000L
14 #define NSEC_PER_USEC 1000L
15 #define NSEC_PER_MSEC 1000000L
16 #define USEC_PER_SEC 1000000L
17 #define NSEC_PER_SEC 1000000000L
18 #define FSEC_PER_SEC 1000000000000000LL
19
20 #define TIME_T_MAX (time_t)((1UL << ((sizeof(time_t) << 3) - 1)) - 1)
21
timespec_equal(const struct timespec * a,const struct timespec * b)22 static inline int timespec_equal(const struct timespec *a,
23 const struct timespec *b)
24 {
25 return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
26 }
27
28 /*
29 * lhs < rhs: return <0
30 * lhs == rhs: return 0
31 * lhs > rhs: return >0
32 */
timespec_compare(const struct timespec * lhs,const struct timespec * rhs)33 static inline int timespec_compare(const struct timespec *lhs, const struct timespec *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_nsec - rhs->tv_nsec;
40 }
41
timeval_compare(const struct timeval * lhs,const struct timeval * rhs)42 static inline int timeval_compare(const struct timeval *lhs, const struct timeval *rhs)
43 {
44 if (lhs->tv_sec < rhs->tv_sec)
45 return -1;
46 if (lhs->tv_sec > rhs->tv_sec)
47 return 1;
48 return lhs->tv_usec - rhs->tv_usec;
49 }
50
51 extern unsigned long mktime(const unsigned int year, const unsigned int mon,
52 const unsigned int day, const unsigned int hour,
53 const unsigned int min, const unsigned int sec);
54
55 extern void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec);
56
57 /*
58 * timespec_add_safe assumes both values are positive and checks
59 * for overflow. It will return TIME_T_MAX if the reutrn would be
60 * smaller then either of the arguments.
61 */
62 extern struct timespec timespec_add_safe(const struct timespec lhs,
63 const struct timespec rhs);
64
65
timespec_add(struct timespec lhs,struct timespec rhs)66 static inline struct timespec timespec_add(struct timespec lhs,
67 struct timespec rhs)
68 {
69 struct timespec ts_delta;
70 set_normalized_timespec(&ts_delta, lhs.tv_sec + rhs.tv_sec,
71 lhs.tv_nsec + rhs.tv_nsec);
72 return ts_delta;
73 }
74
75 /*
76 * sub = lhs - rhs, in normalized form
77 */
timespec_sub(struct timespec lhs,struct timespec rhs)78 static inline struct timespec timespec_sub(struct timespec lhs,
79 struct timespec rhs)
80 {
81 struct timespec ts_delta;
82 set_normalized_timespec(&ts_delta, lhs.tv_sec - rhs.tv_sec,
83 lhs.tv_nsec - rhs.tv_nsec);
84 return ts_delta;
85 }
86
87 #define KTIME_MAX ((s64)~((u64)1 << 63))
88 #if (BITS_PER_LONG == 64)
89 # define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC)
90 #else
91 # define KTIME_SEC_MAX LONG_MAX
92 #endif
93
94 /*
95 * Returns true if the timespec is norm, false if denorm:
96 */
timespec_valid(const struct timespec * ts)97 static inline bool timespec_valid(const struct timespec *ts)
98 {
99 /* Dates before 1970 are bogus */
100 if (ts->tv_sec < 0)
101 return false;
102 /* Can't have more nanoseconds then a second */
103 if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
104 return false;
105 return true;
106 }
107
timespec_valid_strict(const struct timespec * ts)108 static inline bool timespec_valid_strict(const struct timespec *ts)
109 {
110 if (!timespec_valid(ts))
111 return false;
112 /* Disallow values that could overflow ktime_t */
113 if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
114 return false;
115 return true;
116 }
117
118 extern bool persistent_clock_exist;
119
has_persistent_clock(void)120 static inline bool has_persistent_clock(void)
121 {
122 return persistent_clock_exist;
123 }
124
125 extern void read_persistent_clock(struct timespec *ts);
126 extern void read_boot_clock(struct timespec *ts);
127 extern int persistent_clock_is_local;
128 extern int update_persistent_clock(struct timespec now);
129 void timekeeping_init(void);
130 extern int timekeeping_suspended;
131
132 unsigned long get_seconds(void);
133 struct timespec current_kernel_time(void);
134 struct timespec __current_kernel_time(void); /* does not take xtime_lock */
135 struct timespec get_monotonic_coarse(void);
136 void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
137 struct timespec *wtom, struct timespec *sleep);
138 void timekeeping_inject_sleeptime(struct timespec *delta);
139
140 #define CURRENT_TIME (current_kernel_time())
141 #define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 })
142
143 /* Some architectures do not supply their own clocksource.
144 * This is mainly the case in architectures that get their
145 * inter-tick times by reading the counter on their interval
146 * timer. Since these timers wrap every tick, they're not really
147 * useful as clocksources. Wrapping them to act like one is possible
148 * but not very efficient. So we provide a callout these arches
149 * can implement for use with the jiffies clocksource to provide
150 * finer then tick granular time.
151 */
152 #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
153 extern u32 (*arch_gettimeoffset)(void);
154 #endif
155
156 extern void do_gettimeofday(struct timeval *tv);
157 extern int do_settimeofday(const struct timespec *tv);
158 extern int do_sys_settimeofday(const struct timespec *tv,
159 const struct timezone *tz);
160 #define do_posix_clock_monotonic_gettime(ts) ktime_get_ts(ts)
161 extern long do_utimes(int dfd, const char __user *filename, struct timespec *times, int flags);
162 struct itimerval;
163 extern int do_setitimer(int which, struct itimerval *value,
164 struct itimerval *ovalue);
165 extern unsigned int alarm_setitimer(unsigned int seconds);
166 extern int do_getitimer(int which, struct itimerval *value);
167 extern int __getnstimeofday(struct timespec *tv);
168 extern void getnstimeofday(struct timespec *tv);
169 extern void getrawmonotonic(struct timespec *ts);
170 extern void getnstime_raw_and_real(struct timespec *ts_raw,
171 struct timespec *ts_real);
172 extern void getboottime(struct timespec *ts);
173 extern void monotonic_to_bootbased(struct timespec *ts);
174 extern void get_monotonic_boottime(struct timespec *ts);
175
176 extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
177 extern int timekeeping_valid_for_hres(void);
178 extern u64 timekeeping_max_deferment(void);
179 extern int timekeeping_inject_offset(struct timespec *ts);
180 extern s32 timekeeping_get_tai_offset(void);
181 extern void timekeeping_set_tai_offset(s32 tai_offset);
182 extern void timekeeping_clocktai(struct timespec *ts);
183
184 struct tms;
185 extern void do_sys_times(struct tms *);
186
187 /*
188 * Similar to the struct tm in userspace <time.h>, but it needs to be here so
189 * that the kernel source is self contained.
190 */
191 struct tm {
192 /*
193 * the number of seconds after the minute, normally in the range
194 * 0 to 59, but can be up to 60 to allow for leap seconds
195 */
196 int tm_sec;
197 /* the number of minutes after the hour, in the range 0 to 59*/
198 int tm_min;
199 /* the number of hours past midnight, in the range 0 to 23 */
200 int tm_hour;
201 /* the day of the month, in the range 1 to 31 */
202 int tm_mday;
203 /* the number of months since January, in the range 0 to 11 */
204 int tm_mon;
205 /* the number of years since 1900 */
206 long tm_year;
207 /* the number of days since Sunday, in the range 0 to 6 */
208 int tm_wday;
209 /* the number of days since January 1, in the range 0 to 365 */
210 int tm_yday;
211 };
212
213 void time_to_tm(time_t totalsecs, int offset, struct tm *result);
214
215 /**
216 * timespec_to_ns - Convert timespec to nanoseconds
217 * @ts: pointer to the timespec variable to be converted
218 *
219 * Returns the scalar nanosecond representation of the timespec
220 * parameter.
221 */
timespec_to_ns(const struct timespec * ts)222 static inline s64 timespec_to_ns(const struct timespec *ts)
223 {
224 return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
225 }
226
227 /**
228 * timeval_to_ns - Convert timeval to nanoseconds
229 * @ts: pointer to the timeval variable to be converted
230 *
231 * Returns the scalar nanosecond representation of the timeval
232 * parameter.
233 */
timeval_to_ns(const struct timeval * tv)234 static inline s64 timeval_to_ns(const struct timeval *tv)
235 {
236 return ((s64) tv->tv_sec * NSEC_PER_SEC) +
237 tv->tv_usec * NSEC_PER_USEC;
238 }
239
240 /**
241 * ns_to_timespec - Convert nanoseconds to timespec
242 * @nsec: the nanoseconds value to be converted
243 *
244 * Returns the timespec representation of the nsec parameter.
245 */
246 extern struct timespec ns_to_timespec(const s64 nsec);
247
248 /**
249 * ns_to_timeval - Convert nanoseconds to timeval
250 * @nsec: the nanoseconds value to be converted
251 *
252 * Returns the timeval representation of the nsec parameter.
253 */
254 extern struct timeval ns_to_timeval(const s64 nsec);
255
256 /**
257 * timespec_add_ns - Adds nanoseconds to a timespec
258 * @a: pointer to timespec to be incremented
259 * @ns: unsigned nanoseconds value to be added
260 *
261 * This must always be inlined because its used from the x86-64 vdso,
262 * which cannot call other kernel functions.
263 */
timespec_add_ns(struct timespec * a,u64 ns)264 static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
265 {
266 a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
267 a->tv_nsec = ns;
268 }
269
270 #endif
271