return (j + (HZ / MSEC_PER_SEC) - 1)/(HZ / MSEC_PER_SEC);
#else
# if BITS_PER_LONG == 32
- return ((u64)HZ_TO_MSEC_MUL32 * j) >> HZ_TO_MSEC_SHR32;
+ return (HZ_TO_MSEC_MUL32 * j) >> HZ_TO_MSEC_SHR32;
# else
return (j * HZ_TO_MSEC_NUM) / HZ_TO_MSEC_DEN;
# endif
return (j + (HZ / USEC_PER_SEC) - 1)/(HZ / USEC_PER_SEC);
#else
# if BITS_PER_LONG == 32
- return ((u64)HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32;
+ return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32;
# else
return (j * HZ_TO_USEC_NUM) / HZ_TO_USEC_DEN;
# endif
if (HZ > MSEC_PER_SEC && m > jiffies_to_msecs(MAX_JIFFY_OFFSET))
return MAX_JIFFY_OFFSET;
- return ((u64)MSEC_TO_HZ_MUL32 * m + MSEC_TO_HZ_ADJ32)
+ return (MSEC_TO_HZ_MUL32 * m + MSEC_TO_HZ_ADJ32)
>> MSEC_TO_HZ_SHR32;
#endif
}
#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC)
return u * (HZ / USEC_PER_SEC);
#else
- return ((u64)USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32)
+ return (USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32)
>> USEC_TO_HZ_SHR32;
#endif
}
#endif
EXPORT_SYMBOL(jiffies);
+
+/*
+ * Add two timespec values and do a safety check for overflow.
+ * It's assumed that both values are valid (>= 0)
+ */
+struct timespec timespec_add_safe(const struct timespec lhs,
+ const struct timespec rhs)
+{
+ struct timespec res;
+
+ set_normalized_timespec(&res, lhs.tv_sec + rhs.tv_sec,
+ lhs.tv_nsec + rhs.tv_nsec);
+
+ if (res.tv_sec < lhs.tv_sec || res.tv_sec < rhs.tv_sec)
+ res.tv_sec = TIME_T_MAX;
+
+ return res;
+}