Automatic fsck

[Alexander Jones]

Because people are talking about snapshotting a FS in a potentially
broken state, fscking it in the background---whilst continuing to use
it!

Assuming that using a broken FS doesnt hose it (admittedly it
shouldn't), merging a changeset from a broken state into a repaired
state is a process which I think will be extremely fragile and prone
to breakage, /especially/ if attempted FS-agnostically.

I willfully invite people to prove me wrong, just tell me how to
disable it before it eats my data. Or limit your scope a bit and
thrash this out properly, for a single filesystem (hint, Ext3!), on
LKML.