From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jerome Glisse <jglisse@redhat.com>
Subject: Re: [PATCH v1 00/15] Keep track of GUPed pages in fs and block
Date: Wed, 17 Apr 2019 17:19:43 -0400
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To: Boaz Harrosh <boaz@plexistor.com>
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On Tue, Apr 16, 2019 at 10:03:45PM -0400, Jerome Glisse wrote:
> On Wed, Apr 17, 2019 at 04:11:03AM +0300, Boaz Harrosh wrote:
> > On 17/04/19 02:16, Jerome Glisse wrote:
> > > On Wed, Apr 17, 2019 at 01:09:22AM +0300, Boaz Harrosh wrote:
> > >> On 16/04/19 22:57, Jerome Glisse wrote:

[...]

> > >>
> > >> BTW: Are you aware of the users of iov_iter_get_pages_alloc() Do they need fixing too?
> > > 
> > > Yeah and that patchset should address those already, i do not think
> > > i missed any.
> > > 
> > 
> > I could not find a patch for nfs/direct.c where a put_page is called
> > to balance the iov_iter_get_pages_alloc(). Which takes care of for example of
> > the blocklayout.c pages state
> > 
> > So I think the deep Audit needs to be for iov_iter_get_pages and get_user_pages
> > and the balancing of that. And the all of bio_alloc and bio_add_page should stay
> > agnostic to any pege-refs taking/putting
> 
> Will try to get started on that and see if i hit any roadblock. I will
> report once i get my feet wet, or at least before i drown ;)

So far it does not look too bad:

https://cgit.freedesktop.org/~glisse/linux/log/?h=gup-bio-v2

they are few things that will be harder to fit in like splice
and pipe that are populated from GUP.

Cheers,
Jérôme