Re: Status of union-mount?

From: David Howells
Date: Thu Mar 21 2013 - 21:39:12 EST

Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote:

> Hmmm, sorry for asking, but when do you plan to offer a "working"
> union-mount (u-m)?

It's a maze of twisty locking problems - some of which also apply to things
like overlayfs:-(

> What's the status of the user-space tools or are they no more needed?

You need to be able to tell mount(2) that you want a union. This is currently
done with a mount flag, but it might be portable to something in the mount
option string.

> AFAICS the original authors patched e2fsprogs etc. (see Valerie's old
> homepage [1]).

Yeah... I guess fsck programs need to be able to handle whiteout and fallthru
directory entries.

> >> Where does the development happen - in [1]?
> >
> > On a git tree on my PC - which is occasionally mirrored in [1] when I've got
> > it working.
> >
> Development on your local workstation does not look like you do an
> open development.

Excuse me. But it's quite hard to develop this on a remote git tree.
Further, I prefer not to push partially working stuff to my git tree, lest
someone pull it, try playing with it and have their fs eaten.

If someone wants it, I can mail the partially working stuff to them, but not
many people ask.

> So, it's currently only you doing the work on u-m?

Almost entirely, yes.

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