2011-04-06 14:30:49

by Rob Landley

Subject: What's nlmsvc_proc_share() for?

I'm reading through the fs/lockd code, and I read grace.c and svcshare.c
and code such as nlmsvc_share_file() only seems to get called from
nlmsvc_proc_share() (and its cut-and-paste twin nlm4svc_proc_share())...

And as far as I can grep, those last two functions are never called from
anywhere in the kernel source.

The comments say this is for "DOS shares", which presumably doesn't mean
what I think it means because DOS used netbios, not NFS...

What's this code for, and where does it get used? Is it something out
of tree, or some header #define that's glued##together that I'm not
picking up via grep...?

Rob

2011-04-07 03:02:46

by Mi Jinlong

Subject: Re: What's nlmsvc_proc_share() for?

Rob Landley:
> I'm reading through the fs/lockd code, and I read grace.c and svcshare.c
> and code such as nlmsvc_share_file() only seems to get called from
> nlmsvc_proc_share() (and its cut-and-paste twin nlm4svc_proc_share())...
>
> And as far as I can grep, those last two functions are never called from
> anywhere in the kernel source.
>
> The comments say this is for "DOS shares", which presumably doesn't mean
> what I think it means because DOS used netbios, not NFS...
>
> What's this code for, and where does it get used? Is it something out
> of tree, or some header #define that's glued##together that I'm not
> picking up via grep...?

Maybe you can get some info from the following code at fs/lockd/svc4proc.c:

462
463 #define PROC(name, xargt, xrest, argt, rest, respsize) \
464 { .pc_func = (svc_procfunc) nlm4svc_proc_##name, \
465 .pc_decode = (kxdrproc_t) nlm4svc_decode_##xargt, \
466 .pc_encode = (kxdrproc_t) nlm4svc_encode_##xrest, \
467 .pc_release = NULL, \
468 .pc_argsize = sizeof(struct nlm_##argt), \
469 .pc_ressize = sizeof(struct nlm_##rest), \
470 .pc_xdrressize = respsize, \
471 }
472 #define Ck (1+XDR_QUADLEN(NLM_MAXCOOKIELEN)) /* cookie */
473 #define No (1+1024/4) /* netobj */
474 #define St 1 /* status */
475 #define Rg 4 /* range (offset + length) */
476 struct svc_procedure nlmsvc_procedures4[] = {
477 PROC(null, void, void, void, void, 1),
.. ...
497 PROC(none, void, void, void, void, 0),
498 PROC(share, shareargs, shareres, args, res, Ck+St+1),
499 PROC(unshare, shareargs, shareres, args, res, Ck+St+1),
500 PROC(nm_lock, lockargs, res, args, res, Ck+St),
501 PROC(free_all, notify, void, args, void, 1),
502
503 };

--
----
thanks
Mi Jinlong

2011-04-08 01:10:02

by Rob Landley

Subject: Re: What's nlmsvc_proc_share() for?

On 04/06/2011 10:04 PM, Mi Jinlong wrote:
> Rob Landley:
>> What's this code for, and where does it get used? Is it something out
>> of tree, or some header #define that's glued##together that I'm not
>> picking up via grep...?
>
> Maybe you can get some info from the following code at fs/lockd/svc4proc.c:
>
> 462
> 463 #define PROC(name, xargt, xrest, argt, rest, respsize) \
> 464 { .pc_func = (svc_procfunc) nlm4svc_proc_##name, \
...
> 498 PROC(share, shareargs, shareres, args, res, Ck+St+1),

So it's glued##together in a macro. Got it.

Thanks,

Rob