From: Steve French Subject: Re: [RFC][PATCH 0/6] Enhanced file stat system call Date: Thu, 5 May 2016 17:54:54 -0500 Message-ID: References: <20160429125736.23636.47874.stgit@warthog.procyon.org.uk> <5680195.kS2oylQXhI@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: linux-afs@vger.kernel.org, "linux-nfs@vger.kernel.org" , samba-technical , LKML , David Howells , Deepa Dinamani , linux-fsdevel , "linux-ext4@vger.kernel.org" To: Arnd Bergmann Return-path: In-Reply-To: <5680195.kS2oylQXhI@wuerfel> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: samba-technical-bounces@lists.samba.org Sender: "samba-technical" List-Id: linux-ext4.vger.kernel.org On Wed, May 4, 2016 at 8:46 AM, Arnd Bergmann wrote: > On Friday 29 April 2016 13:57:36 David Howells wrote: >> struct statx *buffer); >> >> This is an enhanced file stat function that provides a number of useful >> features, in summary: >> >> (1) More information: creation time, data version number, inode generation >> number and flags. A subset of these is available through a number of >> filesystems (such as CIFS, NFS, AFS, Ext4 and BTRFS). >> > > I have a question about birthtime/creationtime: As we are gaining a way > to read this, should we also provide a way to update it using a new variant > of the utimensat syscall in order to have 'cp -a' create an identical copy, > or is the idea that this is defined as the time that is particular copy > of the inode was created? > > 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 -- Thanks, Steve