Re: [patch] mlock-as-nonroot revisted

[Andrea Arcangeli <andrea@suse.de>]

On Tue, Aug 03, 2004 at 03:01:18PM -0700, Chris Wright wrote:
> * Andrea Arcangeli (andrea@suse.de) wrote:
> > On Tue, Aug 03, 2004 at 11:38:57PM +0200, Arjan van de Ven wrote:
> > > not if you keep track of who locked in the first place and give the credit
> > > back to *that* user (struct).
> > 
> > I wasn't talking about chown above. I mean, where's the truncate that
> > releases the user-struct-bind? 
> 
> I'm not sure what you mean.  Truncate should only update the accounting,
> not break the binding, right?

yep, update the accounting. And with that I meant "releasing" part of
it (accordingly to the size of the truncate, a truncate(0) should
release it all).

> It's meant to be done at object destruction.

where?

Maybe it's just that those are incremental patches and I'm missing the
other part of the patch, but reading those patches I can't see where the
user_subtract_mlock happens when I truncate an hugetlbfs file (or delete
it or whatever). Sure it can't be munlock releasing/_updating_ the user-struct
accounting for fs persistent storage. But if other code takes care of it
then maybe you want to delete the user_subtract_mlock function and use
the other piece that already existed for truncate.

Anyways my overall picture of this is that you're trying to do
filesystem quotas with rlimit which sounds quite flawed.