re-enable IOCB_NOWAIT writes to files v4

[Christoph Hellwig]

On Tue, Jan 06, 2026 at 10:43:49PM +0100, Christian Brauner wrote:
> > Umm, as in my self reply just before heading out for vacation, Julia
> > found issues in it using static type checking tools.  I have a new
> > version that fixes that and sorts out the S_* mess.  So please drop
> > it again for now, I'll resend the fixed version ASAP.
> 
> It has never been pushed nor applied as I saw your mail right before all
> of that.

Thanks.  But maybe you can fix up the applied messages to be more
specific?  We had various issues in the past with them, where they
were sent, but things did not end up in the tree for various reasons.