From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753441AbcEMPIy (ORCPT ); Fri, 13 May 2016 11:08:54 -0400 Received: from mout.kundenserver.de ([212.227.17.13]:60306 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753267AbcEMPIv (ORCPT ); Fri, 13 May 2016 11:08:51 -0400 From: Arnd Bergmann To: Richard Sharpe Cc: Steve French , David Howells , linux-fsdevel , linux-afs@vger.kernel.org, "linux-nfs@vger.kernel.org" , samba-technical , LKML , "linux-ext4@vger.kernel.org" , Deepa Dinamani Subject: Re: [RFC][PATCH 0/6] Enhanced file stat system call Date: Fri, 13 May 2016 17:08:40 +0200 Message-ID: <2640243.Co6Rj7WIl6@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: References: <20160429125736.23636.47874.stgit@warthog.procyon.org.uk> <4211584.odaTcq8sN6@wuerfel> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:5XCnkqMG/OFhOn+SFXHGTEkZXejXXiGSC1AHLQS+5dhLIt5ImAe Vgpyk6W9Dv3II5wix/h2eoc4tGHlp+y8viRsEdBC7WAS4KU1JBqKNK5lVpoHe40kwm1j2wz VmvsJ4pqCUF9zJPV0CeKv5OJ6+GAJ8vJvJhICOx8BfNp63WlNkNSBhg+GaRvtdodjk07FjA CIpUBWWg7p6b+aBAcNauw== X-UI-Out-Filterresults: notjunk:1;V01:K0:GMuENXZnUic=:it6t2XCHS739NydgNuYZxg qYW9mpVN8SXFWzJRIs7mVXiRkF+Nk2Z+qtQpDG201Fbl4EYqzIdbfOWoy3fB74goAMGhEGox6 wXNGMdyo4gdereLyiZI3t+e4SNO5R4jDzg+dFMNuSq3mzsPSL079JsW/Xo4Hp0zYqHDohqpOw ZlaRGN77QtFDJOLwDxGQZttjes9RtVmOBdPn7jtvQMUHAXWMv73kUaXrkDkFyD/BPi+obob5E Nk8uhVGUvQLX4PcW8QymxpDwM8uugcimjuXi38eD7wjjJpQrJ3UUS1zs4wO9b5UCpLH9AhdKY 8ErhNrlU1qwW40bs1Ff0nnq4QrMRu24cNFfNYSgY/6iVIWmSEhGcjIGN9rcn6P81AjnpFOi41 S19PN4viqDsI4tREviLuvrNkf0CjjcOg8M2DRbBOiRbwaqwAUE/9puDMG5thlyp1FAq2t5bmb YLTBm9PkGSrUOPmD8R+yKTN0rKR/U7Wgx252PsD0e2ecviXrOEUKBjceSjh4gTmAFnCWj+O2x i2eN/MRoA/QTqu7wuUiWBpAIF1ShTHEQuqhHtUSYKCvbxwyA8FYC5XE59NQ4029IIOLeAq2v4 W9XkAJ4wr2J1k0ukXeYdTHUQDqENjyC5OR+ZU3tO/VnoeIF1XZqU07L98LM+yilPjMc4/bxbA LmHNBd00i0YxIaodwvqTQEoSCFkswlbqseP7l2cGTTqJ5+9aICHa1qQVAQaO6jsMmxHH+/oTj WftBhuelZIO98CE0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Friday 13 May 2016 07:28:29 Richard Sharpe wrote: > On Mon, May 9, 2016 at 6:09 AM, Arnd Bergmann wrote: > > On Thursday 05 May 2016 21:00:18 Steve French wrote: > >> On Thu, May 5, 2016 at 5:54 PM, Steve French wrote: > >> > On Wed, May 4, 2016 at 8:46 AM, Arnd Bergmann wrote: > >> >> I've discussed this with Deepa in the past, as she is driving the > >> >> convertion of the inode timestamps to timespec64 now, and we will > >> >> need a new version of utimensat for her work as well. I can see good > >> >> reasons either way (allowing updates of btime or disallowing them). > >> > > >> It would help interop with Windows (and presumably Mac) if birth time can be > >> updated > > > > Ok, thanks. That is certainly a good reason in favor. > > > > If nothing else comes up, I guess we can prepare a patch for a new > > utimensat variant to do this and wait for more comments on that. In the meantime I found this LWN article at https://lwn.net/Articles/397442/ Apparently there was a discussion about 6 years ago, without a real conclusion. > Isn't there also a strong case for a setattr call that allows us to > atomically set a collection of attributes from userspace? > > It would seem that network file systems (the clients) could use such features. I had not heard of this before, but that is obviously another option. Most of the attributes returned by xstat are read-only, but I guess this would include uid, gid, {a,b,c,m}time and mode (but not size) along with a 'valid' mask that decides what to set (as in notify_change), right? Arnd