deadlocks with fallocate

[Christoph Hellwig]

On Thu, Oct 15, 2009 at 07:58:05AM +0200, Thomas Neumann wrote:
> I did some more tests, and indeed the patch makes the deadlock go away. Your 
> description of it as a hack makes me somewhat concerned about using it 
> permanently, but hopefully you will find a proper solution ;)

It's basically a flag to say all allocations from this thread should
not recurse back into filesystem code.  I'll either need to change
the allocations manually or keep this flag and write a comment
documenting why.  I'll decide what to on my long airplane ride tomorrow
and will make sure it goes off to Linus' tree ASAP after that.