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 85C086B0069 for ; Wed, 16 Nov 2011 02:10:10 -0500 (EST) Message-ID: <4EC361C0.7040309@redhat.com> Date: Wed, 16 Nov 2011 15:09:52 +0800 From: Cong Wang MIME-Version: 1.0 Subject: Re: [Patch] tmpfs: add fallocate support References: <1321346525-10187-1-git-send-email-amwang@redhat.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Pekka Enberg Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Hugh Dickins , linux-mm@kvack.org, kay.sievers@vrfy.org ao? 2011a1'11ae??15ae?JPY 19:23, Pekka Enberg a??e??: > Hello, > > On Tue, Nov 15, 2011 at 10:42 AM, Amerigo Wang wrote: >> This patch adds fallocate support to tmpfs. I tested this patch >> with the following test case, >> >> % sudo mount -t tmpfs -o size=100 tmpfs /mnt >> % touch /mnt/foobar >> % echo hi> /mnt/foobar >> % fallocate -o 3 -l 5000 /mnt/foobar >> fallocate: /mnt/foobar: fallocate failed: No space left on device >> % fallocate -o 3 -l 3000 /mnt/foobar >> % ls -l /mnt/foobar >> -rw-rw-r-- 1 wangcong wangcong 3003 Nov 15 16:10 /mnt/foobar >> % dd if=/dev/zero of=/mnt/foobar seek=3 bs=1 count=3000 >> 3000+0 records in >> 3000+0 records out >> 3000 bytes (3.0 kB) copied, 0.0153224 s, 196 kB/s >> % hexdump -C /mnt/foobar >> 00000000 68 69 0a 00 00 00 00 00 00 00 00 00 00 00 00 00 |hi..............| >> 00000010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| >> * >> 00000bb0 00 00 00 00 00 00 00 00 00 00 00 |...........| >> 00000bbb >> % cat /mnt/foobar >> hi >> >> Signed-off-by: WANG Cong > > What's the use case for this? > Hi, Pekka, Systemd needs it, see http://lkml.org/lkml/2011/10/20/275. I am adding Kay into Cc. Thanks. -- 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