From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta7.messagelabs.com (mail6.bemta7.messagelabs.com [216.82.255.55]) by kanga.kvack.org (Postfix) with ESMTP id 935AC6B002D for ; Mon, 21 Nov 2011 17:13:35 -0500 (EST) Received: by iaek3 with SMTP id k3so10475659iae.14 for ; Mon, 21 Nov 2011 14:13:33 -0800 (PST) Date: Mon, 21 Nov 2011 14:13:22 -0800 (PST) From: Hugh Dickins Subject: Re: [V2 PATCH] tmpfs: add fallocate support In-Reply-To: <20111121101059.GB17887@infradead.org> Message-ID: References: <1321612791-4764-1-git-send-email-amwang@redhat.com> <20111119100326.GA27967@infradead.org> <20111121101059.GB17887@infradead.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Hellwig Cc: Josef Bacik , Kay Sievers , Cong Wang , linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Pekka Enberg , Dave Hansen , Lennart Poettering , KOSAKI Motohiro , linux-mm@kvack.org On Mon, 21 Nov 2011, Christoph Hellwig wrote: > On Sun, Nov 20, 2011 at 01:39:12PM -0800, Hugh Dickins wrote: > > > But since the present situation is that tmpfs has one interface to > > punching holes, madvise(MADV_REMOVE), that IBM were pushing 5 years ago; > > but ext4 (and others) now a fallocate(FALLOC_FL_PUNCH_HOLE) interface > > which IBM have been pushing this year: we do want to normalize that > > situation and make them all behave the same way. > > FALLOC_FL_PUNCH_HOLE was added by Josef Bacik, who happens to work for > Red Hat, but I doubt he was pushing any corporate agenda there, he was > mostly making btrfs catch up with the 15 year old XFS hole punching > ioctl. Yeah, my apologies to Josef and to IBM and to XFS for my regrettable little outburst of snarkiness :( > > > > And if tmpfs is going to support fallocate(FALLOC_FL_PUNCH_HOLE), > > looking at Amerigo's much more attractive V2 patch, it would seem > > to me perverse to permit the deallocation but fail the allocation. > > Agreed. Thanks a lot for useful info, and saving me looking up the ENOSPC issue. Hugh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org