Re: [PATCH pynfs] Allow server to reject maximum commit offsets

[Trond Myklebust <trond.myklebust@fys.uio.no>]

On Tue, 2010-02-09 at 17:28 -0500, Peter Staubach wrote: 
> J. Bruce Fields wrote:
> > From: J. Bruce Fields <bfields@citi.umich.edu>
> > 
> > These two tests insist that a server must accept commits with offset
> > 2^64-1 and 2^64-2.  I can find no justification in the spec for this
> > requirement.
> > 
> > The linux server was recently changed to reject (with INVAL) offsets
> > over 2^63-1, which is the maximum that the vfs commit routine can
> > accept.  That behavior is consistent with the NFSv3 commit
> > implementation and with the NFSv4 write implementation.
> > 
> 
> I guess that I am missing something.  At least the NFSv3
> COMMIT operation takes an unsigned 64 bit quantity.  That
> would seem to make the test correct, would it not?

The server will not allow you to write to an offset > 2^63-1 (it will
return NFS3ERR_INVAL), so it makes zero sense for the client to try to
issue a COMMIT for an offset starting in that range.

Cheers
  Trond