Re: kern/44208

[Antti Kantee <pooka%cs.hut.fi@localhost>]

On Mon Dec 13 2010 at 00:14:34 +0000, YAMAMOTO Takashi wrote:
> hi,
> 
> >  That's because puffs_advlock is broken ;)
> >  
> >  See kern/43321
> 
> i didn't notice it.  thanks.
> how about abortop?

Well, abortop is kind of an afterthought to be able to run kernel file
servers from libp2k.  For "normal" file servers componentname is always
what is passed down from the kernel, so there is no automatic state in
lookup in userspace.  I guess I could fix protocol so that componentname
would be cached in libpuffs, but that's not a high priority, and that
code is supposed to be changing in weird and wonderous ways anyway.

I added some explanation on the manpage.

> >  I guess an easy way to "fix" it is to just make it call lf_advlock()
> >  in the kernel.  That would at least fix running vi to not give a warning
> >  when run on puffs file systems.
> 
> is there anything which prevents a file system from implementing
> an lf_advlock equivalent (or a more complicated one like NLM) by their own?

I'm under the recollection that it's not possible for some fundamental
reason, but I might misremember.  In any case, the kernel vop should
stop trying to copyin struct flock for anything to even remotely work ;)

-- 
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