Re: [PATCH] VFS: Sanity check mount flags passed to change_mnt_propagation()

[Valerie Aurora <vaurora@redhat.com>]

On Fri, Aug 27, 2010 at 01:51:06PM -0400, Bob Copeland wrote:
> On Fri, Aug 27, 2010 at 1:43 PM, Valerie Aurora <vaurora@redhat.com> wrote:
> > On Thu, Aug 26, 2010 at 07:14:36PM -0600, Matthew Wilcox wrote:
> >> Hrm. ?I think we can do this a bit more pithily.
> >>
> >> ? ? ? /* Only one propagation flag should be set, and no others */
> >> ? ? ? if (hweight32(type) != 1 &&
> >> ? ? ? ? ? (type & ~(MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE))
> >> ? ? ? ? ? ? ? return 0;
> >>
> >> Too clever?
> >
> > I was hoping someone would go find the best bitop for me, thanks. :)
> > hweight32() is an awkward name but the comment makes it clear. ?I'm
> > happy with either.
> >
> > Thanks for the help,
> 
> Didn't read surrounding code, but is that supposed to be '||'?
> 
> Otherwise the case where only a single non-propagation flag is
> set no longer returns 0...

Yes, thanks!

I'll run the test program again before resubmitting. :)

-VAL