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 DA5D76B0069 for ; Sat, 19 Nov 2011 09:15:13 -0500 (EST) Received: by ghrr17 with SMTP id r17so1960473ghr.14 for ; Sat, 19 Nov 2011 06:15:10 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20111119100326.GA27967@infradead.org> References: <1321612791-4764-1-git-send-email-amwang@redhat.com> <20111119100326.GA27967@infradead.org> From: Kay Sievers Date: Sat, 19 Nov 2011 15:14:48 +0100 Message-ID: Subject: Re: [V2 PATCH] tmpfs: add fallocate support Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Hellwig Cc: Cong Wang , linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Pekka Enberg , Hugh Dickins , Dave Hansen , Lennart Poettering , KOSAKI Motohiro , linux-mm@kvack.org On Sat, Nov 19, 2011 at 11:03, Christoph Hellwig wrote: > On Fri, Nov 18, 2011 at 06:39:50PM +0800, Cong Wang wrote: >> It seems that systemd needs tmpfs to support fallocate, >> see http://lkml.org/lkml/2011/10/20/275. This patch adds >> fallocate support to tmpfs. > > What for exactly? =C2=A0Please explain why preallocating on tmpfs would > make any sense. To be able to safely use mmap(), regarding SIGBUS, on files on the /dev/shm filesystem. The glibc fallback loop for -ENOSYS on fallocate is just ugly. Kay -- 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