Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932761AbcDSWll (ORCPT ); Tue, 19 Apr 2016 18:41:41 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:40634 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753657AbcDSWli (ORCPT ); Tue, 19 Apr 2016 18:41:38 -0400 Date: Tue, 19 Apr 2016 23:41:36 +0100 From: Al Viro To: Jeff Layton Cc: linux-cifs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/6] cifs: quit playing games with draining iovecs Message-ID: <20160419224136.GD25498@ZenIV.linux.org.uk> References: <20160409204301.GF25498@ZenIV.linux.org.uk> <20160409205129.GI25498@ZenIV.linux.org.uk> <1461088397.15135.9.camel@poochiereds.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1461088397.15135.9.camel@poochiereds.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 305 Lines: 7 On Tue, Apr 19, 2016 at 01:53:17PM -0400, Jeff Layton wrote: > What's the advantage of using iov_iter_bvec over iov_iter_kvec ? No need to screw with kmap() in the caller; moreover, when it comes to actual copying it gets away with kmap_atomic() just around the memcpy(), which is considerably cheaper.