Re: adding linux syscall fallocate

[David Holland <dholland-tech%netbsd.org@localhost>]

On Sun, Nov 03, 2019 at 07:06:35PM +0100, r0ller wrote:
 > Indeed. That's bad news but thanks for your answer! I've even found
 > this: https://wiki.netbsd.org/projects/project/ffs-fallocate/
 > Are there any details for this project besides that page? I don't
 > know anything about NetBSD internals though if it's not meant for
 > gurus, I'd have a look at it and give it a try.

That's what there is; it is not that difficult (as kernel projects go)
but requires some knowledge of filesystem internals.

Another complication, depending on what your application is trying to
do, is that linux's native fallocate allows allocating blocks beyond
the end of file, which conventional filesystems can't support. If the
thing you're trying to run depends on this behavior, you're probably
SOL. If it doesn't, you can adjust it to use posix_fallocate itself,
so you don't need to muck with the compat layer, but that won't help
with ffs.

-- 
David A. Holland
dholland%netbsd.org@localhost