Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757922Ab0GVRQf (ORCPT ); Thu, 22 Jul 2010 13:16:35 -0400 Received: from mail-out1.uio.no ([129.240.10.57]:52171 "EHLO mail-out1.uio.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751260Ab0GVRQc (ORCPT ); Thu, 22 Jul 2010 13:16:32 -0400 Subject: Re: [PATCH 02/18] xstat: Add a pair of system calls to make extended file stats available [ver #6] From: Trond Myklebust To: Jan Engelhardt Cc: Linus Torvalds , Jeremy Allison , Volker.Lendecke@sernet.de, David Howells , linux-cifs@vger.kernel.org, linux-nfs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org In-Reply-To: References: <20100715021709.5544.64506.stgit@warthog.procyon.org.uk> <20100715021712.5544.44845.stgit@warthog.procyon.org.uk> <30448.1279800887@redhat.com> <20100722162712.GB10352@jeremy-laptop> Content-Type: text/plain; charset="UTF-8" Date: Thu, 22 Jul 2010 13:16:07 -0400 Message-ID: <1279818967.3621.23.camel@heimdal.trondhjem.org> Mime-Version: 1.0 X-Mailer: Evolution 2.30.2 (2.30.2-1.fc13) Content-Transfer-Encoding: 7bit X-UiO-Ratelimit-Test: rcpts/h 12 msgs/h 1 sum rcpts/h 18 sum msgs/h 1 total rcpts 657 max rcpts/h 20 ratelimit 0 X-UiO-Spam-info: not spam, SpamAssassin (score=-5.0, required=5.0, autolearn=disabled, UIO_MAIL_IS_INTERNAL=-5, uiobl=NO, uiouri=NO) X-UiO-Scanned: 6ED0C1EABD3C22ABE5792E99C4FFDF01DBEF11DD X-UiO-SPAM-Test: remote_host: 68.40.206.115 spam_score: -49 maxlevel 80 minaction 2 bait 0 mail/h: 1 total 275 max/h 6 blacklist 0 greylist 0 ratelimit 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1615 Lines: 39 On Thu, 2010-07-22 at 19:03 +0200, Jan Engelhardt wrote: > On Thursday 2010-07-22 18:40, Linus Torvalds wrote: > > >On Thu, Jul 22, 2010 at 9:27 AM, Jeremy Allison wrote: > >> On Thu, Jul 22, 2010 at 08:47:46AM -0700, Linus Torvalds wrote: > >>> Tell me why we shouldn't just do this right? > >> > >> No, ctime isn't the same as Windows "create time". > > > >Umm. What kind of reading problems do you guys have? > > > >I know effin well that ctime isn't the same as Windows create time. > >THAT WAS MY POINT. > > > >But the fact is, th Unix ctime semantics are insane and largely > >useless. There's a damn good reason almost nobody uses ctime under > >unix. > > I beg to differ. ctime is not completely useless. It reflects changes on > the inode for when you don't you change the content. It's like an mtime > for the metadata. It comes useful when you go around in your filesystem > trying to figure out who of your co-admins screwed up the permissions on > /etc/passwd... and if the mtime is the same as that of the last backup, > I can at least have a reasonable assurance that it was /only/ the > metadata that was tampered with. (SHA1 check, yeah yeah, costly on large > files.) Errr... Only if you eliminate utimes() from your syscall table. Otherwise it is trivial to reset the mtime after changing the file contents. Cheers Trond -- 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/