From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx3-rdu2.redhat.com ([66.187.233.73]:47978 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755433AbeEHV5R (ORCPT ); Tue, 8 May 2018 17:57:17 -0400 Subject: Re: [PATCH 2/4] copy_file_range: Perform splice if in/out SB are not same To: Goldwyn Rodrigues , linux-fsdevel@vger.kernel.org Cc: hch@lst.de, smfrench@gmail.com, linux-unionfs@vger.kernel.org, david@fromorbit.com, Goldwyn Rodrigues References: <20180508212405.15297-1-rgoldwyn@suse.de> <20180508212405.15297-3-rgoldwyn@suse.de> From: Florian Weimer Message-ID: Date: Tue, 8 May 2018 23:57:11 +0200 MIME-Version: 1.0 In-Reply-To: <20180508212405.15297-3-rgoldwyn@suse.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On 05/08/2018 11:24 PM, Goldwyn Rodrigues wrote: > While performing copy_file_range(), if superblocks of file_in and > file_out don't match, instead of returning -EXDEV, perform > splice for a faster copy. We have a userspace emulation in glibc which used to be quite faithful, including the EXDEV error (which is not strictly necessary to produce). Should we change glibc to perform a userspace copy if the system call returns EXDEV due to an older kernel? Thanks, Florian