Hi, Deepa Dinamani wrote: > ICMP timestamp messages and IP source route options require > timestamps to be in milliseconds modulo 24 hours from > midnight UTC format. > > Add a time function to support this. The function returns the > required timestamp in network byte order. > > The function also uses y2038 safe time functions and data > structures. > > Signed-off-by: Deepa Dinamani <deepa.ker...@gmail.com> > Cc: John Stultz <john.stu...@linaro.org> > Cc: Thomas Gleixner <t...@linutronix.de> > Cc: "David S. Miller" <da...@davemloft.net> > Cc: Alexey Kuznetsov <kuz...@ms2.inr.ac.ru> > Cc: James Morris <jmor...@namei.org> > Cc: Hideaki YOSHIFUJI <yoshf...@linux-ipv6.org> > Cc: Patrick McHardy <ka...@trash.net> > --- > include/linux/ip.h | 2 ++ > include/linux/time64.h | 3 +++ > kernel/time/time.c | 26 ++++++++++++++++++++++++++ > 3 files changed, 31 insertions(+) > > diff --git a/include/linux/ip.h b/include/linux/ip.h > index 492bc65..edf923e 100644 > --- a/include/linux/ip.h > +++ b/include/linux/ip.h > @@ -34,4 +34,6 @@ static inline struct iphdr *ipip_hdr(const struct sk_buff > *skb) > { > return (struct iphdr *)skb_transport_header(skb); > } > + > +extern __be32 current_nw_timestamp(void); > #endif /* _LINUX_IP_H */ > diff --git a/include/linux/time64.h b/include/linux/time64.h > index 367d5af..5b5db3b 100644 > --- a/include/linux/time64.h > +++ b/include/linux/time64.h > @@ -35,6 +35,9 @@ struct itimerspec64 { > #define NSEC_PER_SEC 1000000000L > #define FSEC_PER_SEC 1000000000000000LL > > +#define SECONDS_PER_DAY 86400 > +#define MSEC_PER_DAY (SECONDS_PER_DAY * MSEC_PER_SEC) > + > /* Located here for timespec[64]_valid_strict */ > #define TIME64_MAX ((s64)~((u64)1 << 63)) > #define KTIME_MAX ((s64)~((u64)1 << 63)) > diff --git a/kernel/time/time.c b/kernel/time/time.c > index 86751c6..6df15df 100644 > --- a/kernel/time/time.c > +++ b/kernel/time/time.c > @@ -245,6 +245,32 @@ struct timespec current_fs_time(struct super_block *sb) > EXPORT_SYMBOL(current_fs_time); > > /* > + * current_nw_timestamp - Return network time > + * > + * Return milliseconds since midnight in network byte order. > + */ > +__be32 current_nw_timestamp(void) > +{ > + u64 now; > + u32 secs; > + u32 msecs; > + struct timespec64 ts; > + > + ktime_get_ts64(&ts); > + > + /* Get secs since midnight. */ > + now = div_u64_rem(ts.tv_sec, SECONDS_PER_DAY, &secs); > + /* Convert to msecs. */ > + msecs = secs * MSEC_PER_SEC; > + /* Convert nsec to msec. */ > + msecs += (u32)ts.tv_nsec/NSEC_PER_MSEC; > + > + /* Convert to network byte order. */ > + return htons(msecs); > +} > +EXPORT_SYMBOL(current_nw_timestamp); > + > +/* > * Convert jiffies to milliseconds and back. > * > * Avoid unnecessary multiplications/divisions in the >
Since net/ipv4/* are the only users, it is enough to put it in under net/ipv4/. -- Hideaki Yoshifuji <hideaki.yoshif...@miraclelinux.com> Technical Division, MIRACLE LINUX CORPORATION