From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [RFC 11/32] xfs: convert to struct inode_time Date: Mon, 02 Jun 2014 21:10:47 +0200 Message-ID: <5585593.Xe5bNQZW47@wuerfel> References: <1401480116-1973111-1-git-send-email-arnd@arndb.de> <1401735504.6065.227.camel@montana.filmlight.ltd.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Chuck Lever Cc: Nicolas Pitre , linux-arch@vger.kernel.org, Linux NFS Mailing List , xfs@oss.sgi.com, LKML Kernel , geert@linux-m68k.org, Christoph Hellwig , john.stultz@linaro.org, "H. Peter Anvin" , linux-fsdevel , lftan@altera.com, tglx@linutronix.de, Roger Willcocks , joseph@codesourcery.com List-Id: linux-arch.vger.kernel.org T24gTW9uZGF5IDAyIEp1bmUgMjAxNCAxNTowNDoyNyBDaHVjayBMZXZlciB3cm90ZToKPiBPbiBK dW4gMiwgMjAxNCwgYXQgMjo1OCBQTSwgUm9nZXIgV2lsbGNvY2tzIDxyb2dlckBmaWxtbGlnaHQu bHRkLnVrPiB3cm90ZToKPiAKPiA+IAo+ID4gT24gTW9uLCAyMDE0LTA2LTAyIGF0IDExOjA0IC0w NDAwLCBDaHVjayBMZXZlciB3cm90ZToKPiA+IAo+ID4+IE5GU3YyLzMgdGltZXN0YW1wcyBhcmUg YSBwYWlyIG9mIHVuc2lnbmVkIDMyLWJpdCB2YWx1ZXM6IG9uZSB2YWx1ZSBmb3IKPiA+PiBzZWNv bmRzIHNpbmNlIG1pZG5pZ2h0IEdNVCBKYW4gMSwgMTk3MCwgYW5kIG9uZSB2YWx1ZSBmb3IgbmFu b3NlY29uZHMuCj4gPj4gKFNlZSB0aGUgZGVmaW5pdGlvbiBvZiBuZnN0aW1lMyBpbiBSRkMgMTgx MykuCj4gPj4gCj4gPiAKPiA+IG5mc3RpbWUzIGNvdWxkIGJlIGV4dGVuZGVkIGJ5IHJlZGVmaW5p bmcgdGhlIG90aGVyd2lzZSB1bnVzZWQKPiA+IG5hbm9zZWNvbmRzIGJpdHN7MzEsMzB9IGFzIHNl Y29uZHN7MzMsMzJ9LCB0byBnaXZlIGEgKHNpZ25lZCkgMzQtYml0Cj4gPiBzZWNvbmRzIGZpZWxk IGFuZCBhbiB1bnNpZ25lZCAzMC1iaXQgbmFub3NlY29uZHMgZmllbGQuCj4gPiAKPiA+IFRoaXMg Y291bGQgcmVwcmVzZW50IDE5NzAgKy8tIDI3MiB5ZWFycy4KPiA+IAo+ID4gU2VydmVycyBjb3Vs ZCBpbmRpY2F0ZSB0aGV5IGNhbiB1bmRlcnN0YW5kIHRoZSBleHRlbmRlZCB0aW1lIGZvcm1hdCBi eQo+ID4gYWRkaW5nIGEgbmV3IEZTSU5GTyBjYXBhYmlsaXR5IC0gRlNGM19DQU5TRVRUSU1FX0VY Lgo+ID4gCj4gPiBDbGllbnRzIHdvdWxkIHVzZSBhIG5ldyBTRVRfVE9fQ0xJRU5UX1RJTUVfRVgg dGltZV9ob3cgZW51bSB3aGVuIHNlbmRpbmcKPiA+IHRpbWVzdGFtcHMgc28gb2xkIHNlcnZlcnMg d291bGQgYmUgcHJvdGVjdGVkIGZyb20gbmV3IGNsaWVudHMuCj4gCj4gWW91IHdvdWxkIGhhdmUg dG8gZ2V0IHRoZSBJRVRG4oCZcyBORlN2NCB3b3JraW5nIGdyb3VwIHRvIHNpZ24gb2ZmIG9uCj4g dGhpcyBjaGFuZ2UuIE90aGVyd2lzZSwgTGludXggd291bGQgYmUgdGhlIG9ubHkgTkZTdjMgaW1w bGVtZW50YXRpb24KPiB0aGF0IHN1cHBvcnRzIHRoZSBleHRlbnNpb24uCj4gCj4gQnV0IEkgc3Vz cGVjdCB0aGUgYW5zd2VyIHlvdeKAmWQgZ2V0IGlzIOKAnFVzZSBORlN2NC7igJ0KCldoaWxlIEkn dmUgbmV2ZXIgZGVhbHQgd2l0aCBhbiBORlMgc3RhbmRhcmRpemF0aW9uLCBJJ2QgYXNzdW1lIHRo aXMgaXMKYSB3b3JrYWJsZSBhbnN3ZXIuIFRoZSBORlN2MiBhbmQgTkZTdjMgZGVmaW5pdGlvbiBj bGVhcmx5IGRlZmluZXMgYSB2YWxpZApyYW5nZSBvZiB0aW1lcyB1bnRpbCAyMTA2IHVzaW5nIHVu c2lnbmVkIHNlY29uZHMsIGFuZCB0aGF0IHNob3VsZCByZWFsbHkKZ2l2ZSBlbm91Z2ggdGltZSB0 byBtaWdyYXRlIHRvIHNvbWV0aGluZyBiZXR0ZXIgKG5vdCBuZWNlc3NhcmlseSBORlN2NCkuCgoJ QXJuZAoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KeGZz IG1haWxpbmcgbGlzdAp4ZnNAb3NzLnNnaS5jb20KaHR0cDovL29zcy5zZ2kuY29tL21haWxtYW4v bGlzdGluZm8veGZzCg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.kundenserver.de ([212.227.126.131]:64161 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752396AbaFBTLN convert rfc822-to-8bit (ORCPT ); Mon, 2 Jun 2014 15:11:13 -0400 From: Arnd Bergmann Subject: Re: [RFC 11/32] xfs: convert to struct inode_time Date: Mon, 02 Jun 2014 21:10:47 +0200 Message-ID: <5585593.Xe5bNQZW47@wuerfel> In-Reply-To: References: <1401480116-1973111-1-git-send-email-arnd@arndb.de> <1401735504.6065.227.camel@montana.filmlight.ltd.uk> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset="utf-8" Sender: linux-arch-owner@vger.kernel.org List-ID: To: Chuck Lever Cc: Roger Willcocks , Nicolas Pitre , linux-arch@vger.kernel.org, Linux NFS Mailing List , LKML Kernel , lftan@altera.com, Christoph Hellwig , john.stultz@linaro.org, "H. Peter Anvin" , linux-fsdevel , geert@linux-m68k.org, tglx@linutronix.de, xfs@oss.sgi.com, joseph@codesourcery.com Message-ID: <20140602191047.RAs70zmwqWlAvQ-nEe9_43i9x91V1jbtwn1eggQEY8k@z> On Monday 02 June 2014 15:04:27 Chuck Lever wrote: > On Jun 2, 2014, at 2:58 PM, Roger Willcocks wrote: > > > > > On Mon, 2014-06-02 at 11:04 -0400, Chuck Lever wrote: > > > >> NFSv2/3 timestamps are a pair of unsigned 32-bit values: one value for > >> seconds since midnight GMT Jan 1, 1970, and one value for nanoseconds. > >> (See the definition of nfstime3 in RFC 1813). > >> > > > > nfstime3 could be extended by redefining the otherwise unused > > nanoseconds bits{31,30} as seconds{33,32}, to give a (signed) 34-bit > > seconds field and an unsigned 30-bit nanoseconds field. > > > > This could represent 1970 +/- 272 years. > > > > Servers could indicate they can understand the extended time format by > > adding a new FSINFO capability - FSF3_CANSETTIME_EX. > > > > Clients would use a new SET_TO_CLIENT_TIME_EX time_how enum when sending > > timestamps so old servers would be protected from new clients. > > You would have to get the IETF’s NFSv4 working group to sign off on > this change. Otherwise, Linux would be the only NFSv3 implementation > that supports the extension. > > But I suspect the answer you’d get is “Use NFSv4.” While I've never dealt with an NFS standardization, I'd assume this is a workable answer. The NFSv2 and NFSv3 definition clearly defines a valid range of times until 2106 using unsigned seconds, and that should really give enough time to migrate to something better (not necessarily NFSv4). Arnd