From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jamie Lokier Subject: Re: [patch 0/3] make splice more generic Date: Thu, 14 May 2009 21:27:06 +0100 Message-ID: <20090514202706.GB20363@shareable.org> References: <20090507133734.450612199@szeredi.hu> <20090511121247.GZ4694@kernel.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Miklos Szeredi , Max Kellermann , torvalds@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: Jens Axboe Return-path: Received: from mail2.shareable.org ([80.68.89.115]:42799 "EHLO mail2.shareable.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754152AbZENU1Y (ORCPT ); Thu, 14 May 2009 16:27:24 -0400 Content-Disposition: inline In-Reply-To: <20090511121247.GZ4694@kernel.dk> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Jens Axboe wrote: > SPLICE_F_MOVE is a soft flag in that it will move if it > can, but not fail if it can't. According to local man page, it's not even that. SPLICE_F_MOVE [...] The initial implementation of this flag was buggy: therefore starting in Linux 2.6.21 it is a *no-op* (but is still permitted in a splice() call); in the future, a correct implementation may be restored. > Perhaps we should add a flag that does pass back an error if we > can't just move pages around, SPLICE_F_STRICT or something like > that. What should it do in cases where the kernel would choose to copy data, i.e. data that isn't a whole page? -- Jamie