Re: [PATCH v2 00/20] Overlayfs inodes index

Amir Goldstein
2017-06-07T14:58:19Z

On Wed, Jun 7, 2017 at 10:51 AM, Amir Goldstein <amir73il@gmail.com> wrote:
> Miklos,
>
> This set is an independent series a top of current overlayfs-next.
> I yanked all the dependencies from previous postings (consistent d_ino,
> dir_lock, verify_lower) and included everything needed in this posting.
>
> This work introcuding the inodes index opt-in feature, which provides:
> - Hardlinks are not broken on copy up
> - Infrastructure for overlayfs NFS export
>
> Hardlink copy up tests including concurrent copy up of lower hardlinks
> are available on my xfstests dev branch [1].
>
> There are some more TODO items before this is ready for v4.13, but I'd
> love to hear what you think about the direction this has taken so far.
>
> Thanks,
> Amir.
>
> TODO:
> - Consistency of lower and upper hardlinks (*)
> - Cleanup stale and orphan index entries on mount (**)
> - Document the inodes index feature
>
> (*) When any lower hardlink has been copied up, we get the indexed
> upper inode on lookup of all lower hardlinks and since they all
> share the same overlay inode, they have the same 'realinode'.
> Opening the lower hardlinks for read gives that lower inode
> and not the indexed upper 'realinode'. The tests in [1] demostrate
> this problem.

Miklos,

I have fix for the lower/upper hardlink inconsistency issue.
Pushed the patches to branch:
https://github.com/amir73il/linux/commits/ovl-hardlinks-rocopyup

It now passes all the xfstests hardlink copy up tests [1].
Note that you will need to use my unionmount-testsuite dev branch [2]
to test with inodes index enabled.
The one test that fails the constant inode verification on v4.12-rc1
(due to hardlink non constant ino) now passes:
./run --ov=1 --samefs rename-mass-5

Thanks,
Amir.

[1] https://github.com/amir73il/xfstests/commits/overlayfs-devel
[2] https://github.com/amir73il/unionmount-testsuite/commits/overlayfs-devel