From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?Q?P=c3=a1draig_Brady?= Subject: Re: [PATCH v5 8/9] vfs: Add vfs_copy_file_range() support for pagecache copies Date: Wed, 14 Oct 2015 20:39:21 +0100 Message-ID: <561EAF69.9000905@draigBrady.com> References: <1443634014-3026-1-git-send-email-Anna.Schumaker@Netapp.com> <1443634014-3026-9-git-send-email-Anna.Schumaker@Netapp.com> <20151011142203.GA31867@infradead.org> <20151012231749.GC11398@birch.djwong.org> <561E980C.9010509@Netapp.com> <20151014182701.GC31225@infradead.org> <20151014184946.GA15214@infradead.org> <561EA997.9020402@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <561EA997.9020402@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org To: Austin S Hemmelgarn , Andy Lutomirski , Christoph Hellwig Cc: Anna Schumaker , "Darrick J. Wong" , linux-nfs@vger.kernel.org, Linux btrfs Developers List , Linux FS Devel , Linux API , Zach Brown , Al Viro , Chris Mason , Michael Kerrisk-manpages , andros@netapp.com List-Id: linux-api@vger.kernel.org On 14/10/15 20:14, Austin S Hemmelgarn wrote: > On 2015-10-14 14:53, Andy Lutomirski wrote: >> On Wed, Oct 14, 2015 at 11:49 AM, Christoph Hellwig wrote: >>> On Wed, Oct 14, 2015 at 11:38:13AM -0700, Andy Lutomirski wrote: >>>> One might argue that reflink is like copy + immediate dedupe. >>> >>> Not, it's not. It's all that and more, because it is an operation = that >>> is atomic vs other writes to the file and it's an operation that ei= ther >>> clones the whole range or nothing. That's a very important differe= nce. >> >> Fair enough. >> >> Would copy_file_range without the reflink option removed still be >> permitted to link blocks on supported filesystems (btrfs and maybe >> XFS)? > I would argue that it should have such functionality, but not do so b= y=20 > default (maybe add some option to tell it to ask the FS to accelerate= =20 > the copy operation?). Heh, so back to the REFLINK flag :) TBH given the overlap between "copy" and "reflink", I quite like the REFLINK flag as a general interface to reflink. thanks, P=C3=A1draig -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html