Re: [nfsv4] Can NFSv4.2 operations be optional on a per server file system basis?

[David Noveck <[e-mail]>]

I think the right error to return in the case in which allocate is
implemented by the server but not supported on a particular fs is
NFS4ERR_SERVERFAULT. The case we are talking about is an error that is not
otherwise provided for, just as the definition of that error states.

On Sun, Oct 10, 2021, 3:33 PM Rick Macklem <[e-mail]> wrote:

> Thomas Haynes wrote:
> >> On Oct 10, 2021, at 7:07 AM, Rick Macklem <[e-mail]> wrote:
> >>
> >> Hi,
> >>
> >> I'm guessing the answer is "no", but I figured I'd ask just to make
> sure,
> >> since RFC7862 states that operations are optional, but does not clarify
> >> beyond that.
> >>
> >> So, if an NFSv4.2 server exports two file systems, where one of them can
> >> perform the operation and the other cannot, is the server allowed to
> >> reply NFS4ERR_NOTSUPP for the operation when attempted on files
> >> in the file system that cannot perform the operation?
> >>
> >> Thanks, rick
> >> ps: In FreeBSD, UFS can do Allocate, but ZFS cannot.
> >>
> >> _______________________________________________
> >> nfsv4 mailing list
> >> [e-mail]
> >> https://www.ietf.org/mailman/listinfo/nfsv4
> >
> >
> >Hi Rick,
> >
> >The answer is “no”.
> That's what I thought.
>
> >But the question is very interesting. NFS4ERR_INVAL might be the most
> appropriate of the allowed errors, but >pretty sure you do not want to be
> returning that.
> Yea, EINVAL is the correct response for posix_fallocate(), but the Linux
> fallocate() uses ENOTSUPP and uses
> EINVAL for lots of other things. Since returning EINVAL for a ZFS export
> was flagged as a bug by testers
> during last week's Bakeathon, I'd agree that EINVAL wouldn't work.
>
> >Of the not allowed errors, I think that NFS4ERR_OFFLOAD_DENIED is closest
> to what you want. You actually want an >NFS4ERR_ALLOCATE_DENIED. It would
> mean that ALLOCATE was supported, but not allowed for the given file.
> >
> >And I have no clue how easy it would be to drive that into the standard’s
> body any more. :-)
> I think I'll just have to NFS4ERR_NOTSUPP for Allocate unless the server
> knows that all file systems
> (and DSs for the pNFS case) can do it.
>
> Thanks, rick
> ps: Tom, is hs-anvil going to stick around on the Bat VPN for a while? I
> have a client side race/deadlock
>       when testing against it and, if I come up with a fix, it would be
> nice to be able to test against it?
>
> Tom
>
> _______________________________________________
> nfsv4 mailing list
> [e-mail]
> https://www.ietf.org/mailman/listinfo/nfsv4
>