Re: [PATCH v8 0/9] Overlayfs: constant st_ino/d_ino for non-samefs

[Miklos Szeredi <miklos@szeredi.hu>]

On Fri, Mar 23, 2018 at 3:00 PM, Vivek Goyal <vgoyal@redhat.com> wrote:
> On Thu, Mar 22, 2018 at 04:36:25PM +0100, Miklos Szeredi wrote:
>> On Thu, Mar 22, 2018 at 4:07 PM, Amir Goldstein <amir73il@gmail.com> wrote:
>> > On Thu, Mar 22, 2018 at 4:19 PM, Miklos Szeredi <miklos@szeredi.hu> wrote:
>> >> On Sat, Mar 17, 2018 at 9:29 AM, Amir Goldstein <amir73il@gmail.com> wrote:
>> >>> On Wed, Nov 8, 2017 at 12:53 PM, Miklos Szeredi <miklos@szeredi.hu> wrote:
>> >>>> On Tue, Nov 7, 2017 at 5:58 PM, Amir Goldstein <amir73il@gmail.com> wrote:
>> >>> [...]
>> >>>
>> >>>> The -oxino patches are interesting, but maybe we should leave them
>> >>>> brewing for another cycle.  Do you agree?
>> >>>>
>> >>>
>> >>> Miklos,
>> >>>
>> >>> FYI, I pushed ovl-xino branch that is rebased on v4.16-rc5 and on top
>> >>> of a few fixes in branch ovl-fixes:
>> >>> * 5668064a61f6 - ovl: set i_ino to the value of st_ino for NFS export
>> >>> * 579515ad5c75 - ovl: opaque xattr should overrule redirect xattr
>> >>> * 0161362aeab7 - ovl: fix lookup with middle layer opaque dir and
>> >>> absolute path redirects
>> >>
>> >> I'm a bit confused about this last one.  It's in Vivek's lookup fixes
>> >> series as well but in a slightly different form.  Which one should I
>> >> be looking at?
>> >>
>> >
>> > Vivek's patch is the later version (so v2).
>> > There are 2 differences between v1 and v2:
>> > 1. Vivek's commit message is more elaborate, so should take it.
>> > 2. Vivek's patch sets only d->stop and not d->opaque
>> > This difference is purely semantic, because d->opaque is
>> > ignored in ovl_lookup() for anything but the upper layer.
>> >
>> > I am fine with the semantic change, but wasn't sure if you
>> > had other meaning in mind w.r.t d->opaque and metadata
>> > going forward.
>>
>> I think clearing opaque it is the correct thing to do even if it
>> doesn't have any effect.
>
> Hi Miklos,
>
> I am fine with anything. I was just trying to make it semantically
> more clear. That is when ovl_lookup_layer() is called, what do fields
> in ovl_data{} reflect. I felt that "->opaque" should reflect the
> property of last element of the path. And if we stick to it, then we
> should not clear d->opauque when absolute redirect is found.

Right.  In the light of the rest of your patchset it makes sense.

Thanks,
Miklos