Re: [RFC PATCH v2] ovl: suppress negative dentry in lookup

[Dave Chinner <david@fromorbit.com>]

On Tue, May 12, 2020 at 11:30:43AM +0200, Miklos Szeredi wrote:
> On Tue, May 12, 2020 at 10:55 AM Amir Goldstein <amir73il@gmail.com> wrote:
> >
> > On Tue, May 12, 2020 at 11:32 AM Miklos Szeredi <miklos@szeredi.hu> wrote:
> > >
> > > On Tue, May 12, 2020 at 10:50:31AM +0300, Amir Goldstein wrote:
> 
> > > diff --git a/include/linux/namei.h b/include/linux/namei.h
> > > index a4bb992623c4..4896eeeeea46 100644
> > > --- a/include/linux/namei.h
> > > +++ b/include/linux/namei.h
> > > @@ -49,6 +49,8 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT};
> > >  /* LOOKUP_* flags which do scope-related checks based on the dirfd. */
> > >  #define LOOKUP_IS_SCOPED (LOOKUP_BENEATH | LOOKUP_IN_ROOT)
> > >
> > > +#define LOOKUP_NO_NEGATIVE     0x200000 /* Hint: don't cache negative */
> > > +
> >
> > The language lawyers will call this double negative, but I do
> > prefer this over LOOKUP_POSITIVE :-)
> 
> Maybe LOOKUP_NOCACHE_NEGATIVE...

"DONTCACHE" is the terminaology we've used for telling the inode
cache not to cache inodes....

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com