diff options
Diffstat (limited to 'kernel/time/time.c')
| -rw-r--r-- | kernel/time/time.c | 169 |
1 files changed, 158 insertions, 11 deletions
diff --git a/kernel/time/time.c b/kernel/time/time.c index f4198af60fee..642647f5046b 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -365,11 +365,14 @@ SYSCALL_DEFINE1(adjtimex_time32, struct old_timex32 __user *, utp) } #endif -/* - * Convert jiffies to milliseconds and back. +/** + * jiffies_to_msecs - Convert jiffies to milliseconds + * @j: jiffies value * * Avoid unnecessary multiplications/divisions in the - * two most common HZ cases: + * two most common HZ cases. + * + * Return: milliseconds value */ unsigned int jiffies_to_msecs(const unsigned long j) { @@ -388,6 +391,12 @@ unsigned int jiffies_to_msecs(const unsigned long j) } EXPORT_SYMBOL(jiffies_to_msecs); +/** + * jiffies_to_usecs - Convert jiffies to microseconds + * @j: jiffies value + * + * Return: microseconds value + */ unsigned int jiffies_to_usecs(const unsigned long j) { /* @@ -408,8 +417,15 @@ unsigned int jiffies_to_usecs(const unsigned long j) } EXPORT_SYMBOL(jiffies_to_usecs); -/* +/** * mktime64 - Converts date to seconds. + * @year0: year to convert + * @mon0: month to convert + * @day: day to convert + * @hour: hour to convert + * @min: minute to convert + * @sec: second to convert + * * Converts Gregorian date to seconds since 1970-01-01 00:00:00. * Assumes input in normal date format, i.e. 1980-12-31 23:59:59 * => year=1980, mon=12, day=31, hour=23, min=59, sec=59. @@ -427,6 +443,8 @@ EXPORT_SYMBOL(jiffies_to_usecs); * * An encoding of midnight at the end of the day as 24:00:00 - ie. midnight * tomorrow - (allowable under ISO 8601) is supported. + * + * Return: seconds since the epoch time for the given input date */ time64_t mktime64(const unsigned int year0, const unsigned int mon0, const unsigned int day, const unsigned int hour, @@ -471,8 +489,7 @@ EXPORT_SYMBOL(ns_to_kernel_old_timeval); * Set seconds and nanoseconds field of a timespec variable and * normalize to the timespec storage format * - * Note: The tv_nsec part is always in the range of - * 0 <= tv_nsec < NSEC_PER_SEC + * Note: The tv_nsec part is always in the range of 0 <= tv_nsec < NSEC_PER_SEC. * For negative values only the tv_sec field is negative ! */ void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec) @@ -501,7 +518,7 @@ EXPORT_SYMBOL(set_normalized_timespec64); * ns_to_timespec64 - Convert nanoseconds to timespec64 * @nsec: the nanoseconds value to be converted * - * Returns the timespec64 representation of the nsec parameter. + * Return: the timespec64 representation of the nsec parameter. */ struct timespec64 ns_to_timespec64(s64 nsec) { @@ -548,6 +565,8 @@ EXPORT_SYMBOL(ns_to_timespec64); * runtime. * The _msecs_to_jiffies helpers are the HZ dependent conversion * routines found in include/linux/jiffies.h + * + * Return: jiffies value */ unsigned long __msecs_to_jiffies(const unsigned int m) { @@ -560,6 +579,12 @@ unsigned long __msecs_to_jiffies(const unsigned int m) } EXPORT_SYMBOL(__msecs_to_jiffies); +/** + * __usecs_to_jiffies: - convert microseconds to jiffies + * @u: time in milliseconds + * + * Return: jiffies value + */ unsigned long __usecs_to_jiffies(const unsigned int u) { if (u > jiffies_to_usecs(MAX_JIFFY_OFFSET)) @@ -568,7 +593,10 @@ unsigned long __usecs_to_jiffies(const unsigned int u) } EXPORT_SYMBOL(__usecs_to_jiffies); -/* +/** + * timespec64_to_jiffies - convert a timespec64 value to jiffies + * @value: pointer to &struct timespec64 + * * The TICK_NSEC - 1 rounds up the value to the next resolution. Note * that a remainder subtract here would not do the right thing as the * resolution values don't fall on second boundaries. I.e. the line: @@ -582,8 +610,9 @@ EXPORT_SYMBOL(__usecs_to_jiffies); * * The >> (NSEC_JIFFIE_SC - SEC_JIFFIE_SC) converts the scaled nsec * value to a scaled second value. + * + * Return: jiffies value */ - unsigned long timespec64_to_jiffies(const struct timespec64 *value) { @@ -601,6 +630,11 @@ timespec64_to_jiffies(const struct timespec64 *value) } EXPORT_SYMBOL(timespec64_to_jiffies); +/** + * jiffies_to_timespec64 - convert jiffies value to &struct timespec64 + * @jiffies: jiffies value + * @value: pointer to &struct timespec64 + */ void jiffies_to_timespec64(const unsigned long jiffies, struct timespec64 *value) { @@ -618,6 +652,13 @@ EXPORT_SYMBOL(jiffies_to_timespec64); /* * Convert jiffies/jiffies_64 to clock_t and back. */ + +/** + * jiffies_to_clock_t - Convert jiffies to clock_t + * @x: jiffies value + * + * Return: jiffies converted to clock_t (CLOCKS_PER_SEC) + */ clock_t jiffies_to_clock_t(unsigned long x) { #if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0 @@ -632,6 +673,12 @@ clock_t jiffies_to_clock_t(unsigned long x) } EXPORT_SYMBOL(jiffies_to_clock_t); +/** + * clock_t_to_jiffies - Convert clock_t to jiffies + * @x: clock_t value + * + * Return: clock_t value converted to jiffies + */ unsigned long clock_t_to_jiffies(unsigned long x) { #if (HZ % USER_HZ)==0 @@ -649,6 +696,12 @@ unsigned long clock_t_to_jiffies(unsigned long x) } EXPORT_SYMBOL(clock_t_to_jiffies); +/** + * jiffies_64_to_clock_t - Convert jiffies_64 to clock_t + * @x: jiffies_64 value + * + * Return: jiffies_64 value converted to 64-bit "clock_t" (CLOCKS_PER_SEC) + */ u64 jiffies_64_to_clock_t(u64 x) { #if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0 @@ -671,6 +724,12 @@ u64 jiffies_64_to_clock_t(u64 x) } EXPORT_SYMBOL(jiffies_64_to_clock_t); +/** + * nsec_to_clock_t - Convert nsec value to clock_t + * @x: nsec value + * + * Return: nsec value converted to 64-bit "clock_t" (CLOCKS_PER_SEC) + */ u64 nsec_to_clock_t(u64 x) { #if (NSEC_PER_SEC % USER_HZ) == 0 @@ -687,6 +746,12 @@ u64 nsec_to_clock_t(u64 x) #endif } +/** + * jiffies64_to_nsecs - Convert jiffies64 to nanoseconds + * @j: jiffies64 value + * + * Return: nanoseconds value + */ u64 jiffies64_to_nsecs(u64 j) { #if !(NSEC_PER_SEC % HZ) @@ -697,6 +762,12 @@ u64 jiffies64_to_nsecs(u64 j) } EXPORT_SYMBOL(jiffies64_to_nsecs); +/** + * jiffies64_to_msecs - Convert jiffies64 to milliseconds + * @j: jiffies64 value + * + * Return: milliseconds value + */ u64 jiffies64_to_msecs(const u64 j) { #if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ) @@ -719,6 +790,8 @@ EXPORT_SYMBOL(jiffies64_to_msecs); * note: * NSEC_PER_SEC = 10^9 = (5^9 * 2^9) = (1953125 * 512) * ULLONG_MAX ns = 18446744073.709551615 secs = about 584 years + * + * Return: nsecs converted to jiffies64 value */ u64 nsecs_to_jiffies64(u64 n) { @@ -750,6 +823,8 @@ EXPORT_SYMBOL(nsecs_to_jiffies64); * note: * NSEC_PER_SEC = 10^9 = (5^9 * 2^9) = (1953125 * 512) * ULLONG_MAX ns = 18446744073.709551615 secs = about 584 years + * + * Return: nsecs converted to jiffies value */ unsigned long nsecs_to_jiffies(u64 n) { @@ -757,10 +832,16 @@ unsigned long nsecs_to_jiffies(u64 n) } EXPORT_SYMBOL_GPL(nsecs_to_jiffies); -/* - * Add two timespec64 values and do a safety check for overflow. +/** + * timespec64_add_safe - Add two timespec64 values and do a safety check + * for overflow. + * @lhs: first (left) timespec64 to add + * @rhs: second (right) timespec64 to add + * * It's assumed that both values are valid (>= 0). * And, each timespec64 is in normalized form. + * + * Return: sum of @lhs + @rhs */ struct timespec64 timespec64_add_safe(const struct timespec64 lhs, const struct timespec64 rhs) @@ -778,6 +859,15 @@ struct timespec64 timespec64_add_safe(const struct timespec64 lhs, return res; } +/** + * get_timespec64 - get user's time value into kernel space + * @ts: destination &struct timespec64 + * @uts: user's time value as &struct __kernel_timespec + * + * Handles compat or 32-bit modes. + * + * Return: %0 on success or negative errno on error + */ int get_timespec64(struct timespec64 *ts, const struct __kernel_timespec __user *uts) { @@ -801,6 +891,14 @@ int get_timespec64(struct timespec64 *ts, } EXPORT_SYMBOL_GPL(get_timespec64); +/** + * put_timespec64 - convert timespec64 value to __kernel_timespec format and + * copy the latter to userspace + * @ts: input &struct timespec64 + * @uts: user's &struct __kernel_timespec + * + * Return: %0 on success or negative errno on error + */ int put_timespec64(const struct timespec64 *ts, struct __kernel_timespec __user *uts) { @@ -839,6 +937,15 @@ static int __put_old_timespec32(const struct timespec64 *ts64, return copy_to_user(cts, &ts, sizeof(ts)) ? -EFAULT : 0; } +/** + * get_old_timespec32 - get user's old-format time value into kernel space + * @ts: destination &struct timespec64 + * @uts: user's old-format time value (&struct old_timespec32) + * + * Handles X86_X32_ABI compatibility conversion. + * + * Return: %0 on success or negative errno on error + */ int get_old_timespec32(struct timespec64 *ts, const void __user *uts) { if (COMPAT_USE_64BIT_TIME) @@ -848,6 +955,16 @@ int get_old_timespec32(struct timespec64 *ts, const void __user *uts) } EXPORT_SYMBOL_GPL(get_old_timespec32); +/** + * put_old_timespec32 - convert timespec64 value to &struct old_timespec32 and + * copy the latter to userspace + * @ts: input &struct timespec64 + * @uts: user's &struct old_timespec32 + * + * Handles X86_X32_ABI compatibility conversion. + * + * Return: %0 on success or negative errno on error + */ int put_old_timespec32(const struct timespec64 *ts, void __user *uts) { if (COMPAT_USE_64BIT_TIME) @@ -857,6 +974,13 @@ int put_old_timespec32(const struct timespec64 *ts, void __user *uts) } EXPORT_SYMBOL_GPL(put_old_timespec32); +/** + * get_itimerspec64 - get user's &struct __kernel_itimerspec into kernel space + * @it: destination &struct itimerspec64 + * @uit: user's &struct __kernel_itimerspec + * + * Return: %0 on success or negative errno on error + */ int get_itimerspec64(struct itimerspec64 *it, const struct __kernel_itimerspec __user *uit) { @@ -872,6 +996,14 @@ int get_itimerspec64(struct itimerspec64 *it, } EXPORT_SYMBOL_GPL(get_itimerspec64); +/** + * put_itimerspec64 - convert &struct itimerspec64 to __kernel_itimerspec format + * and copy the latter to userspace + * @it: input &struct itimerspec64 + * @uit: user's &struct __kernel_itimerspec + * + * Return: %0 on success or negative errno on error + */ int put_itimerspec64(const struct itimerspec64 *it, struct __kernel_itimerspec __user *uit) { @@ -887,6 +1019,13 @@ int put_itimerspec64(const struct itimerspec64 *it, } EXPORT_SYMBOL_GPL(put_itimerspec64); +/** + * get_old_itimerspec32 - get user's &struct old_itimerspec32 into kernel space + * @its: destination &struct itimerspec64 + * @uits: user's &struct old_itimerspec32 + * + * Return: %0 on success or negative errno on error + */ int get_old_itimerspec32(struct itimerspec64 *its, const struct old_itimerspec32 __user *uits) { @@ -898,6 +1037,14 @@ int get_old_itimerspec32(struct itimerspec64 *its, } EXPORT_SYMBOL_GPL(get_old_itimerspec32); +/** + * put_old_itimerspec32 - convert &struct itimerspec64 to &struct + * old_itimerspec32 and copy the latter to userspace + * @its: input &struct itimerspec64 + * @uits: user's &struct old_itimerspec32 + * + * Return: %0 on success or negative errno on error + */ int put_old_itimerspec32(const struct itimerspec64 *its, struct old_itimerspec32 __user *uits) { |