Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755742Ab3CaFuo (ORCPT ); Sun, 31 Mar 2013 01:50:44 -0400 Received: from mail-oa0-f48.google.com ([209.85.219.48]:61453 "EHLO mail-oa0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753562Ab3CaFum convert rfc822-to-8bit (ORCPT ); Sun, 31 Mar 2013 01:50:42 -0400 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT Subject: Re: New copyfile system call - discuss before LSF? References: <512606DF.5050706@redhat.com> <4FA345DA4F4AE44899BD2B03EEEC2FA9235D998C@SACEXCMBX04-PRD.hq.netapp.com> <512635D2.4090207@redhat.com> <51267CEB.8070805@redhat.com> <4FA345DA4F4AE44899BD2B03EEEC2FA9235DAA99@SACEXCMBX04-PRD.hq.netapp.com> <20130221222449.GY22221@lenny.home.zabbo.net> <512BD44C.40907@amacapital.net> <20130226210232.GA19510@logfs.org> <20130330194933.GB1005@amd.pavel.ucw.cz> <08D26E22-3856-43A4-8835-48C86CC5F71C@dilger.ca> <20130330214509.GB4322@amd.pavel.ucw.cz> From: AEDilger Gmail Mime-Version: 1.0 (1.0) In-Reply-To: <20130330214509.GB4322@amd.pavel.ucw.cz> Message-Id: Date: Sat, 30 Mar 2013 22:38:35 -0700 Cc: Andreas Dilger , =?utf-8?Q?J=C3=B6rn_Engel?= , Andy Lutomirski , Zach Brown , "Myklebust, Trond" , Paolo Bonzini , Ric Wheeler , Linux FS Devel , "linux-kernel@vger.kernel.org" , "Chris L. Mason" , Christoph Hellwig , Alexander Viro , "Martin K. Petersen" , Hannes Reinecke , Joel Becker To: Pavel Machek X-Mailer: iPhone Mail (10B146) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1349 Lines: 27 On 2013-03-30, at 14:45, Pavel Machek wrote: > On Sat 2013-03-30 13:08:39, Andreas Dilger wrote: >> On 2013-03-30, at 12:49 PM, Pavel Machek wrote: >>> Hmm, really? AFAICT it would be simple to provide an >>> open_deleted_file("directory") syscall. You'd open_deleted_file(), >>> copy source file into it, then fsync(), then link it into filesystem. >>> >>> That should have atomicity properties reflected. >> >> Actually, the open_deleted_file() syscall is quite useful for many >> different things all by itself. Lots of applications need to create >> temporary files that are unlinked at application failure (without a >> race if app crashes after creating the file, but before unlinking). >> It also avoids exposing temporary files into the namespace if other >> applications are accessing the directory. > > Hmm. open_deleted_file() will still need to get a directory... so it > will still need a path. Perhaps open("/foo/bar/mnt", O_DELETED) would > be acceptable interface? Yes, that would be reasonable, and/or possibly openat(fd, NULL, AT_FDCWD|AT_UNLINKED)? Cheers, Andreas-- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/