X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=kernel%2Ftime.c;h=7e09cfed2f9807e9d8ecb92bd218b5081d4005c1;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=142a4bd5771eb649d0fe4e40559bfeee3ed9b2f2;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git diff --git a/kernel/time.c b/kernel/time.c index 142a4bd57..7e09cfed2 100644 --- a/kernel/time.c +++ b/kernel/time.c @@ -22,13 +22,23 @@ * "A Kernel Model for Precision Timekeeping" by Dave Mills * Allow time_constant larger than MAXTC(6) for NTP v4 (MAXTC == 10) * (Even though the technical memorandum forbids it) + * 2004-07-14 Christoph Lameter + * Added getnstimeofday to allow the posix timer functions to return + * with nanosecond accuracy */ #include #include +#include #include #include +#include +#include +#include +#include + #include +#include /* * The timezone where the local system is located. Used as a default by some @@ -38,22 +48,20 @@ struct timezone sys_tz; EXPORT_SYMBOL(sys_tz); -#if !defined(__alpha__) && !defined(__ia64__) +#ifdef __ARCH_WANT_SYS_TIME /* * sys_time() can be implemented in user-level using * sys_gettimeofday(). Is this for backwards compatibility? If so, * why not move it into the appropriate arch directory (for those * architectures that need it). - * - * XXX This function is NOT 64-bit clean! */ -asmlinkage long sys_time(int * tloc) +asmlinkage long sys_time(time_t __user * tloc) { - int i; + time_t i; struct timeval tv; - do_gettimeofday(&tv); + vx_gettimeofday(&tv); i = tv.tv_sec; if (tloc) { @@ -70,27 +78,31 @@ asmlinkage long sys_time(int * tloc) * architectures that need it). */ -asmlinkage long sys_stime(time_t *tptr) +asmlinkage long sys_stime(time_t __user *tptr) { struct timespec tv; + int err; - if (!capable(CAP_SYS_TIME)) - return -EPERM; if (get_user(tv.tv_sec, tptr)) return -EFAULT; tv.tv_nsec = 0; - do_settimeofday(&tv); + + err = security_settime(&tv, NULL); + if (err) + return err; + + vx_settimeofday(&tv); return 0; } -#endif +#endif /* __ARCH_WANT_SYS_TIME */ asmlinkage long sys_gettimeofday(struct timeval __user *tv, struct timezone __user *tz) { if (likely(tv != NULL)) { struct timeval ktv; - do_gettimeofday(&ktv); + vx_gettimeofday(&ktv); if (copy_to_user(tv, &ktv, sizeof(ktv))) return -EFAULT; } @@ -117,12 +129,12 @@ asmlinkage long sys_gettimeofday(struct timeval __user *tv, struct timezone __us * as real UNIX machines always do it. This avoids all headaches about * daylight saving times and warping kernel clocks. */ -inline static void warp_clock(void) +static inline void warp_clock(void) { write_seqlock_irq(&xtime_lock); wall_to_monotonic.tv_sec -= sys_tz.tz_minuteswest * 60; xtime.tv_sec += sys_tz.tz_minuteswest * 60; - time_interpolator_update(sys_tz.tz_minuteswest * 60 * NSEC_PER_SEC); + time_interpolator_reset(); write_sequnlock_irq(&xtime_lock); clock_was_set(); } @@ -141,10 +153,15 @@ inline static void warp_clock(void) int do_sys_settimeofday(struct timespec *tv, struct timezone *tz) { static int firsttime = 1; + int error = 0; + + if (tv && !timespec_valid(tv)) + return -EINVAL; + + error = security_settime(tv, tz); + if (error) + return error; - if (!capable(CAP_SYS_TIME)) - return -EPERM; - if (tz) { /* SMP safe, global irq locking makes it work. */ sys_tz = *tz; @@ -159,7 +176,7 @@ int do_sys_settimeofday(struct timespec *tv, struct timezone *tz) /* SMP safe, again the code in arch/foo/time.c should * globally block out interrupts when it runs. */ - return do_settimeofday(tv); + return vx_settimeofday(tv); } return 0; } @@ -185,240 +202,273 @@ asmlinkage long sys_settimeofday(struct timeval __user *tv, return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL); } -long pps_offset; /* pps time offset (us) */ -long pps_jitter = MAXTIME; /* time dispersion (jitter) (us) */ +asmlinkage long sys_adjtimex(struct timex __user *txc_p) +{ + struct timex txc; /* Local copy of parameter */ + int ret; -long pps_freq; /* frequency offset (scaled ppm) */ -long pps_stabil = MAXFREQ; /* frequency dispersion (scaled ppm) */ + /* Copy the user data space into the kernel copy + * structure. But bear in mind that the structures + * may change + */ + if(copy_from_user(&txc, txc_p, sizeof(struct timex))) + return -EFAULT; + ret = do_adjtimex(&txc); + return copy_to_user(txc_p, &txc, sizeof(struct timex)) ? -EFAULT : ret; +} -long pps_valid = PPS_VALID; /* pps signal watchdog counter */ +inline struct timespec current_kernel_time(void) +{ + struct timespec now; + unsigned long seq; -int pps_shift = PPS_SHIFT; /* interval duration (s) (shift) */ + do { + seq = read_seqbegin(&xtime_lock); + + now = xtime; + } while (read_seqretry(&xtime_lock, seq)); -long pps_jitcnt; /* jitter limit exceeded */ -long pps_calcnt; /* calibration intervals */ -long pps_errcnt; /* calibration errors */ -long pps_stbcnt; /* stability limit exceeded */ + return now; +} -/* hook for a loadable hardpps kernel module */ -void (*hardpps_ptr)(struct timeval *); +EXPORT_SYMBOL(current_kernel_time); -/* adjtimex mainly allows reading (and writing, if superuser) of - * kernel time-keeping variables. used by xntpd. +/** + * current_fs_time - Return FS time + * @sb: Superblock. + * + * Return the current time truncated to the time granularity supported by + * the fs. */ -int do_adjtimex(struct timex *txc) +struct timespec current_fs_time(struct super_block *sb) { - long ltemp, mtemp, save_adjust; - int result; + struct timespec now = current_kernel_time(); + return timespec_trunc(now, sb->s_time_gran); +} +EXPORT_SYMBOL(current_fs_time); - /* In order to modify anything, you gotta be super-user! */ - if (txc->modes && !capable(CAP_SYS_TIME)) - return -EPERM; - - /* Now we validate the data before disabling interrupts */ +/** + * timespec_trunc - Truncate timespec to a granularity + * @t: Timespec + * @gran: Granularity in ns. + * + * Truncate a timespec to a granularity. gran must be smaller than a second. + * Always rounds down. + * + * This function should be only used for timestamps returned by + * current_kernel_time() or CURRENT_TIME, not with do_gettimeofday() because + * it doesn't handle the better resolution of the later. + */ +struct timespec timespec_trunc(struct timespec t, unsigned gran) +{ + /* + * Division is pretty slow so avoid it for common cases. + * Currently current_kernel_time() never returns better than + * jiffies resolution. Exploit that. + */ + if (gran <= jiffies_to_usecs(1) * 1000) { + /* nothing */ + } else if (gran == 1000000000) { + t.tv_nsec = 0; + } else { + t.tv_nsec -= t.tv_nsec % gran; + } + return t; +} +EXPORT_SYMBOL(timespec_trunc); - if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT) - /* singleshot must not be used with any other mode bits */ - if (txc->modes != ADJ_OFFSET_SINGLESHOT) - return -EINVAL; +#ifdef CONFIG_TIME_INTERPOLATION +void getnstimeofday (struct timespec *tv) +{ + unsigned long seq,sec,nsec; - if (txc->modes != ADJ_OFFSET_SINGLESHOT && (txc->modes & ADJ_OFFSET)) - /* adjustment Offset limited to +- .512 seconds */ - if (txc->offset <= - MAXPHASE || txc->offset >= MAXPHASE ) - return -EINVAL; + do { + seq = read_seqbegin(&xtime_lock); + sec = xtime.tv_sec; + nsec = xtime.tv_nsec+time_interpolator_get_offset(); + } while (unlikely(read_seqretry(&xtime_lock, seq))); - /* if the quartz is off by more than 10% something is VERY wrong ! */ - if (txc->modes & ADJ_TICK) - if (txc->tick < 900000/USER_HZ || - txc->tick > 1100000/USER_HZ) - return -EINVAL; + while (unlikely(nsec >= NSEC_PER_SEC)) { + nsec -= NSEC_PER_SEC; + ++sec; + } + tv->tv_sec = sec; + tv->tv_nsec = nsec; +} +EXPORT_SYMBOL_GPL(getnstimeofday); - write_seqlock_irq(&xtime_lock); - result = time_state; /* mostly `TIME_OK' */ +int do_settimeofday (struct timespec *tv) +{ + time_t wtm_sec, sec = tv->tv_sec; + long wtm_nsec, nsec = tv->tv_nsec; - /* Save for later - semantics of adjtime is to return old value */ - save_adjust = time_next_adjust ? time_next_adjust : time_adjust; + if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) + return -EINVAL; -#if 0 /* STA_CLOCKERR is never set yet */ - time_status &= ~STA_CLOCKERR; /* reset STA_CLOCKERR */ -#endif - /* If there are input parameters, then process them */ - if (txc->modes) + write_seqlock_irq(&xtime_lock); { - if (txc->modes & ADJ_STATUS) /* only set allowed bits */ - time_status = (txc->status & ~STA_RONLY) | - (time_status & STA_RONLY); - - if (txc->modes & ADJ_FREQUENCY) { /* p. 22 */ - if (txc->freq > MAXFREQ || txc->freq < -MAXFREQ) { - result = -EINVAL; - goto leave; - } - time_freq = txc->freq - pps_freq; - } - - if (txc->modes & ADJ_MAXERROR) { - if (txc->maxerror < 0 || txc->maxerror >= NTP_PHASE_LIMIT) { - result = -EINVAL; - goto leave; - } - time_maxerror = txc->maxerror; - } + wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec); + wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); - if (txc->modes & ADJ_ESTERROR) { - if (txc->esterror < 0 || txc->esterror >= NTP_PHASE_LIMIT) { - result = -EINVAL; - goto leave; - } - time_esterror = txc->esterror; - } + set_normalized_timespec(&xtime, sec, nsec); + set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); - if (txc->modes & ADJ_TIMECONST) { /* p. 24 */ - if (txc->constant < 0) { /* NTP v4 uses values > 6 */ - result = -EINVAL; - goto leave; - } - time_constant = txc->constant; - } - - if (txc->modes & ADJ_OFFSET) { /* values checked earlier */ - if (txc->modes == ADJ_OFFSET_SINGLESHOT) { - /* adjtime() is independent from ntp_adjtime() */ - if ((time_next_adjust = txc->offset) == 0) - time_adjust = 0; - } - else if ( time_status & (STA_PLL | STA_PPSTIME) ) { - ltemp = (time_status & (STA_PPSTIME | STA_PPSSIGNAL)) == - (STA_PPSTIME | STA_PPSSIGNAL) ? - pps_offset : txc->offset; - - /* - * Scale the phase adjustment and - * clamp to the operating range. - */ - if (ltemp > MAXPHASE) - time_offset = MAXPHASE << SHIFT_UPDATE; - else if (ltemp < -MAXPHASE) - time_offset = -(MAXPHASE << SHIFT_UPDATE); - else - time_offset = ltemp << SHIFT_UPDATE; - - /* - * Select whether the frequency is to be controlled - * and in which mode (PLL or FLL). Clamp to the operating - * range. Ugly multiply/divide should be replaced someday. - */ - - if (time_status & STA_FREQHOLD || time_reftime == 0) - time_reftime = xtime.tv_sec; - mtemp = xtime.tv_sec - time_reftime; - time_reftime = xtime.tv_sec; - if (time_status & STA_FLL) { - if (mtemp >= MINSEC) { - ltemp = (time_offset / mtemp) << (SHIFT_USEC - - SHIFT_UPDATE); - if (ltemp < 0) - time_freq -= -ltemp >> SHIFT_KH; - else - time_freq += ltemp >> SHIFT_KH; - } else /* calibration interval too short (p. 12) */ - result = TIME_ERROR; - } else { /* PLL mode */ - if (mtemp < MAXSEC) { - ltemp *= mtemp; - if (ltemp < 0) - time_freq -= -ltemp >> (time_constant + - time_constant + - SHIFT_KF - SHIFT_USEC); - else - time_freq += ltemp >> (time_constant + - time_constant + - SHIFT_KF - SHIFT_USEC); - } else /* calibration interval too long (p. 12) */ - result = TIME_ERROR; - } - if (time_freq > time_tolerance) - time_freq = time_tolerance; - else if (time_freq < -time_tolerance) - time_freq = -time_tolerance; - } /* STA_PLL || STA_PPSTIME */ - } /* txc->modes & ADJ_OFFSET */ - if (txc->modes & ADJ_TICK) { - tick_usec = txc->tick; - tick_nsec = TICK_USEC_TO_NSEC(tick_usec); - } - } /* txc->modes */ -leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0 - || ((time_status & (STA_PPSFREQ|STA_PPSTIME)) != 0 - && (time_status & STA_PPSSIGNAL) == 0) - /* p. 24, (b) */ - || ((time_status & (STA_PPSTIME|STA_PPSJITTER)) - == (STA_PPSTIME|STA_PPSJITTER)) - /* p. 24, (c) */ - || ((time_status & STA_PPSFREQ) != 0 - && (time_status & (STA_PPSWANDER|STA_PPSERROR)) != 0)) - /* p. 24, (d) */ - result = TIME_ERROR; - - if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT) - txc->offset = save_adjust; - else { - if (time_offset < 0) - txc->offset = -(-time_offset >> SHIFT_UPDATE); - else - txc->offset = time_offset >> SHIFT_UPDATE; + time_adjust = 0; /* stop active adjtime() */ + time_status |= STA_UNSYNC; + time_maxerror = NTP_PHASE_LIMIT; + time_esterror = NTP_PHASE_LIMIT; + time_interpolator_reset(); } - txc->freq = time_freq + pps_freq; - txc->maxerror = time_maxerror; - txc->esterror = time_esterror; - txc->status = time_status; - txc->constant = time_constant; - txc->precision = time_precision; - txc->tolerance = time_tolerance; - txc->tick = tick_usec; - txc->ppsfreq = pps_freq; - txc->jitter = pps_jitter >> PPS_AVG; - txc->shift = pps_shift; - txc->stabil = pps_stabil; - txc->jitcnt = pps_jitcnt; - txc->calcnt = pps_calcnt; - txc->errcnt = pps_errcnt; - txc->stbcnt = pps_stbcnt; write_sequnlock_irq(&xtime_lock); - do_gettimeofday(&txc->time); - return(result); + clock_was_set(); + return 0; } +EXPORT_SYMBOL(do_settimeofday); -asmlinkage long sys_adjtimex(struct timex __user *txc_p) +void do_gettimeofday (struct timeval *tv) { - struct timex txc; /* Local copy of parameter */ - int ret; + unsigned long seq, nsec, usec, sec, offset; + do { + seq = read_seqbegin(&xtime_lock); + offset = time_interpolator_get_offset(); + sec = xtime.tv_sec; + nsec = xtime.tv_nsec; + } while (unlikely(read_seqretry(&xtime_lock, seq))); - /* Copy the user data space into the kernel copy - * structure. But bear in mind that the structures - * may change - */ - if(copy_from_user(&txc, txc_p, sizeof(struct timex))) - return -EFAULT; - ret = do_adjtimex(&txc); - return copy_to_user(txc_p, &txc, sizeof(struct timex)) ? -EFAULT : ret; + usec = (nsec + offset) / 1000; + + while (unlikely(usec >= USEC_PER_SEC)) { + usec -= USEC_PER_SEC; + ++sec; + } + + tv->tv_sec = sec; + tv->tv_usec = usec; } -struct timespec current_kernel_time(void) +EXPORT_SYMBOL(do_gettimeofday); + + +#else +#ifndef CONFIG_GENERIC_TIME +/* + * Simulate gettimeofday using do_gettimeofday which only allows a timeval + * and therefore only yields usec accuracy + */ +void getnstimeofday(struct timespec *tv) { - struct timespec now; - unsigned long seq; + struct timeval x; - do { - seq = read_seqbegin(&xtime_lock); - - now = xtime; - } while (read_seqretry(&xtime_lock, seq)); + vx_gettimeofday(&x); + tv->tv_sec = x.tv_sec; + tv->tv_nsec = x.tv_usec * NSEC_PER_USEC; +} +EXPORT_SYMBOL_GPL(getnstimeofday); +#endif +#endif - return now; +/* 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. + * + * [For the Julian calendar (which was used in Russia before 1917, + * Britain & colonies before 1752, anywhere else before 1582, + * and is still in use by some communities) leave out the + * -year/100+year/400 terms, and add 10.] + * + * This algorithm was first published by Gauss (I think). + * + * WARNING: this function will overflow on 2106-02-07 06:28:16 on + * machines were long is 32-bit! (However, as time_t is signed, we + * will already get problems at other places on 2038-01-19 03:14:08) + */ +unsigned long +mktime(const unsigned int year0, const unsigned int mon0, + const unsigned int day, const unsigned int hour, + const unsigned int min, const unsigned int sec) +{ + unsigned int mon = mon0, year = year0; + + /* 1..12 -> 11,12,1..10 */ + if (0 >= (int) (mon -= 2)) { + mon += 12; /* Puts Feb last since it has leap day */ + year -= 1; + } + + return ((((unsigned long) + (year/4 - year/100 + year/400 + 367*mon/12 + day) + + year*365 - 719499 + )*24 + hour /* now have hours */ + )*60 + min /* now have minutes */ + )*60 + sec; /* finally seconds */ } -EXPORT_SYMBOL(current_kernel_time); +EXPORT_SYMBOL(mktime); + +/** + * set_normalized_timespec - set timespec sec and nsec parts and normalize + * + * @ts: pointer to timespec variable to be set + * @sec: seconds to set + * @nsec: nanoseconds to set + * + * 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 + * For negative values only the tv_sec field is negative ! + */ +void set_normalized_timespec(struct timespec *ts, time_t sec, long nsec) +{ + while (nsec >= NSEC_PER_SEC) { + nsec -= NSEC_PER_SEC; + ++sec; + } + while (nsec < 0) { + nsec += NSEC_PER_SEC; + --sec; + } + ts->tv_sec = sec; + ts->tv_nsec = nsec; +} + +/** + * ns_to_timespec - Convert nanoseconds to timespec + * @nsec: the nanoseconds value to be converted + * + * Returns the timespec representation of the nsec parameter. + */ +struct timespec ns_to_timespec(const s64 nsec) +{ + struct timespec ts; + + if (!nsec) + return (struct timespec) {0, 0}; + + ts.tv_sec = div_long_long_rem_signed(nsec, NSEC_PER_SEC, &ts.tv_nsec); + if (unlikely(nsec < 0)) + set_normalized_timespec(&ts, ts.tv_sec, ts.tv_nsec); + + return ts; +} + +/** + * ns_to_timeval - Convert nanoseconds to timeval + * @nsec: the nanoseconds value to be converted + * + * Returns the timeval representation of the nsec parameter. + */ +struct timeval ns_to_timeval(const s64 nsec) +{ + struct timespec ts = ns_to_timespec(nsec); + struct timeval tv; + + tv.tv_sec = ts.tv_sec; + tv.tv_usec = (suseconds_t) ts.tv_nsec / 1000; + + return tv; +} #if (BITS_PER_LONG < 64) u64 get_jiffies_64(void)