[PATCH]: Enable snapshots of mirrors

[Petr Rockai <prockai@redhat.com>]

Hi,

it would be great if you could convert your tests into actual testcase code,
maybe gathered all under test/t-snapshots-of-mirrors.sh -- this would help
prevent any possible regressions in the future. It would also mean we remember
all the information you needed to gather to conduct these tests.

May you need any assistance with writing the tests, please don't hesitate to
contact me (IRC probably works best).

Also,

Jonathan Brassow <jbrassow@redhat.com> writes:
> lvconvert:
> + down convert works (mirror to linear)
> + down convert works (mirror to mirror)
> + up convert works (linear to mirror) - both background and foreground
> - up convert doesn't work (mirror to mirror) - disabled in lvconvert and
> err msg added
> + convert between log types works (core <-> disk/redundant)
could you please check what lvconvert --repair does under a snapshot? I would
probably look into the mirror->mirror upconversion, although that's only
relevant for a repair of 3+-way mirror.

The t-lvconvert-repair.sh script should aid you in constructing a testcase.

Thanks!
   Petr.