Re: [PATCH 1/6] fs: add hole punching to fallocate

Jan Kara
2010-11-16T11:42:16Z

On Tue 16-11-10 12:16:11, Jan Kara wrote:
> On Mon 15-11-10 12:05:18, Josef Bacik wrote:
> > diff --git a/fs/open.c b/fs/open.c
> > index 4197b9e..ab8dedf 100644
> > --- a/fs/open.c
> > +++ b/fs/open.c
> > @@ -223,7 +223,7 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
> > return -EINVAL;
> >
> > /* Return error if mode is not supported */
> > - if (mode && !(mode & FALLOC_FL_KEEP_SIZE))
> > + if (mode && (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)))
> Why not just:
> if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)) ?
And BTW, since FALLOC_FL_PUNCH_HOLE does not change the file size, should
not we enforce that FALLOC_FL_KEEP_SIZE is / is not set? I don't mind too
much which way but keeping it ambiguous (ignored) in the interface usually
proves as a bad idea in future when we want to further extend the interface...

Honza
--
Jan Kara <jack@suse.cz>
SUSE Labs, CR