Fix compat32 for ntp_adjtime(2).

[kib]

Summary

Add kern_ntp_adjtime(9).
struct timex is not 32-bit safe, it uses longs for members. Provide translation.

[cy]

I don't see any issues worth noting.

[brooks]

I'd be tempted to pass timex_copyin and timex_copyout function pointers to kern_ntp_adjtime rather than having duplicate code in sys_ and freebsd32_. That would also simplify a future compat syscall implementation.

sys/kern/kern_ntptime.c

1089–1109 ↗

(On Diff #80286)

This looks like it's part of a future syscall revision, not the compat change?

[kib]

In D27471#613779, @brooks wrote:

I'd be tempted to pass timex_copyin and timex_copyout function pointers to kern_ntp_adjtime rather than having duplicate code in sys_ and freebsd32_. That would also simplify a future compat syscall implementation.

Right now it seems there will be no compat syscall, ie struct timex is not going to change.

Do you still want copyin callbacks there ? It is more overhead in code for rather trivial wrappers IMO.

[kib]

Remove stray chunk.

[brooks]

Without a compat syscall it seems fine to leave this as is.