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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /include/linux/time64.h
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'include/linux/time64.h')
-rw-r--r--include/linux/time64.h171
1 files changed, 171 insertions, 0 deletions
diff --git a/include/linux/time64.h b/include/linux/time64.h
new file mode 100644
index 000000000..f1bcea8c1
--- /dev/null
+++ b/include/linux/time64.h
@@ -0,0 +1,171 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_TIME64_H
+#define _LINUX_TIME64_H
+
+#include <linux/math64.h>
+#include <vdso/time64.h>
+
+typedef __s64 time64_t;
+typedef __u64 timeu64_t;
+
+#include <uapi/linux/time.h>
+
+struct timespec64 {
+ time64_t tv_sec; /* seconds */
+ long tv_nsec; /* nanoseconds */
+};
+
+struct itimerspec64 {
+ struct timespec64 it_interval;
+ struct timespec64 it_value;
+};
+
+/* Parameters used to convert the timespec values: */
+#define PSEC_PER_NSEC 1000L
+
+/* Located here for timespec[64]_valid_strict */
+#define TIME64_MAX ((s64)~((u64)1 << 63))
+#define TIME64_MIN (-TIME64_MAX - 1)
+
+#define KTIME_MAX ((s64)~((u64)1 << 63))
+#define KTIME_MIN (-KTIME_MAX - 1)
+#define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC)
+#define KTIME_SEC_MIN (KTIME_MIN / NSEC_PER_SEC)
+
+/*
+ * Limits for settimeofday():
+ *
+ * To prevent setting the time close to the wraparound point time setting
+ * is limited so a reasonable uptime can be accomodated. Uptime of 30 years
+ * should be really sufficient, which means the cutoff is 2232. At that
+ * point the cutoff is just a small part of the larger problem.
+ */
+#define TIME_UPTIME_SEC_MAX (30LL * 365 * 24 *3600)
+#define TIME_SETTOD_SEC_MAX (KTIME_SEC_MAX - TIME_UPTIME_SEC_MAX)
+
+static inline int timespec64_equal(const struct timespec64 *a,
+ const struct timespec64 *b)
+{
+ return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
+}
+
+/*
+ * lhs < rhs: return <0
+ * lhs == rhs: return 0
+ * lhs > rhs: return >0
+ */
+static inline int timespec64_compare(const struct timespec64 *lhs, const struct timespec64 *rhs)
+{
+ if (lhs->tv_sec < rhs->tv_sec)
+ return -1;
+ if (lhs->tv_sec > rhs->tv_sec)
+ return 1;
+ return lhs->tv_nsec - rhs->tv_nsec;
+}
+
+extern void set_normalized_timespec64(struct timespec64 *ts, time64_t sec, s64 nsec);
+
+static inline struct timespec64 timespec64_add(struct timespec64 lhs,
+ struct timespec64 rhs)
+{
+ struct timespec64 ts_delta;
+ set_normalized_timespec64(&ts_delta, lhs.tv_sec + rhs.tv_sec,
+ lhs.tv_nsec + rhs.tv_nsec);
+ return ts_delta;
+}
+
+/*
+ * sub = lhs - rhs, in normalized form
+ */
+static inline struct timespec64 timespec64_sub(struct timespec64 lhs,
+ struct timespec64 rhs)
+{
+ struct timespec64 ts_delta;
+ set_normalized_timespec64(&ts_delta, lhs.tv_sec - rhs.tv_sec,
+ lhs.tv_nsec - rhs.tv_nsec);
+ return ts_delta;
+}
+
+/*
+ * Returns true if the timespec64 is norm, false if denorm:
+ */
+static inline bool timespec64_valid(const struct timespec64 *ts)
+{
+ /* Dates before 1970 are bogus */
+ if (ts->tv_sec < 0)
+ return false;
+ /* Can't have more nanoseconds then a second */
+ if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
+ return false;
+ return true;
+}
+
+static inline bool timespec64_valid_strict(const struct timespec64 *ts)
+{
+ if (!timespec64_valid(ts))
+ return false;
+ /* Disallow values that could overflow ktime_t */
+ if ((unsigned long long)ts->tv_sec >= KTIME_SEC_MAX)
+ return false;
+ return true;
+}
+
+static inline bool timespec64_valid_settod(const struct timespec64 *ts)
+{
+ if (!timespec64_valid(ts))
+ return false;
+ /* Disallow values which cause overflow issues vs. CLOCK_REALTIME */
+ if ((unsigned long long)ts->tv_sec >= TIME_SETTOD_SEC_MAX)
+ return false;
+ return true;
+}
+
+/**
+ * timespec64_to_ns - Convert timespec64 to nanoseconds
+ * @ts: pointer to the timespec64 variable to be converted
+ *
+ * Returns the scalar nanosecond representation of the timespec64
+ * parameter.
+ */
+static inline s64 timespec64_to_ns(const struct timespec64 *ts)
+{
+ /* Prevent multiplication overflow / underflow */
+ if (ts->tv_sec >= KTIME_SEC_MAX)
+ return KTIME_MAX;
+
+ if (ts->tv_sec <= KTIME_SEC_MIN)
+ return KTIME_MIN;
+
+ return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
+}
+
+/**
+ * ns_to_timespec64 - Convert nanoseconds to timespec64
+ * @nsec: the nanoseconds value to be converted
+ *
+ * Returns the timespec64 representation of the nsec parameter.
+ */
+extern struct timespec64 ns_to_timespec64(s64 nsec);
+
+/**
+ * timespec64_add_ns - Adds nanoseconds to a timespec64
+ * @a: pointer to timespec64 to be incremented
+ * @ns: unsigned nanoseconds value to be added
+ *
+ * This must always be inlined because its used from the x86-64 vdso,
+ * which cannot call other kernel functions.
+ */
+static __always_inline void timespec64_add_ns(struct timespec64 *a, u64 ns)
+{
+ a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
+ a->tv_nsec = ns;
+}
+
+/*
+ * timespec64_add_safe assumes both values are positive and checks for
+ * overflow. It will return TIME64_MAX in case of overflow.
+ */
+extern struct timespec64 timespec64_add_safe(const struct timespec64 lhs,
+ const struct timespec64 rhs);
+
+#endif /* _LINUX_TIME64_H */