From: Theodore Ts'o Subject: Re: [Gluster-devel] regressions due to 64-bit ext4 directory cookies Date: Wed, 13 Feb 2013 17:47:20 -0500 Message-ID: <20130213224720.GE5938@thunk.org> References: <20130212202841.GC10267@fieldses.org> <20130213040003.GB2614@thunk.org> <20130213133131.GE14195@fieldses.org> <20130213151455.GB17431@thunk.org> <20130213151953.GJ14195@fieldses.org> <20130213153654.GC17431@thunk.org> <20130213162059.GL14195@fieldses.org> <20130213222052.GD5938@thunk.org> <20130213224141.GU14195@fieldses.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Anand Avati , Bernd Schubert , sandeen-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, gluster-devel-qX2TKyscuCcdnm+yROfE0A@public.gmane.org To: "J. Bruce Fields" Return-path: Content-Disposition: inline In-Reply-To: <20130213224141.GU14195-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org> Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-ext4.vger.kernel.org On Wed, Feb 13, 2013 at 05:41:41PM -0500, J. Bruce Fields wrote: > > What if we have an ioctl or a process personality flag where a broken > > application can tell the file system "I'm broken, please give me a > > degraded telldir/seekdir cookie"? That way we don't penalize programs > > that are doing the right thing, while providing some accomodation for > > programs who are abusing the telldir cookie. > > Yeah, if there's a simple way to do that, maybe it would be worth it. Doing this as an ioctl which gets called right after opendir, i.e (ignoring error checking): DIR *dir = opendir("/foo/bar/baz"); ioctl(dirfd(dir), EXT4_IOC_DEGRADED_READDIR, 1); ... should be quite easy. It would be a very ext3/4 specific thing, though. It would be more work to get something in as a process personality flag, mostly due to the politics of assiging a bit out of the bitfield. - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html