* "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 <linux/module.h>
#include <linux/timex.h>
+#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/smp_lock.h>
+#include <linux/syscalls.h>
+#include <linux/security.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+
#include <asm/uaccess.h>
#include <asm/unistd.h>
* 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 __user * 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) {
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;
}
{
if (likely(tv != NULL)) {
struct timeval ktv;
- do_gettimeofday(&ktv);
+ vx_gettimeofday(&ktv);
if (copy_to_user(tv, &ktv, sizeof(ktv)))
return -EFAULT;
}
* 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();
}
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;
/* 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;
}
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)