From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755660AbbLAPPP (ORCPT ); Tue, 1 Dec 2015 10:15:15 -0500 Received: from 8bytes.org ([81.169.241.247]:60271 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751985AbbLAPPM (ORCPT ); Tue, 1 Dec 2015 10:15:12 -0500 Date: Tue, 1 Dec 2015 16:15:10 +0100 From: Joerg Roedel To: Yong Wu Cc: iommu@lists.linux-foundation.org, Will Deacon , linux-kernel@vger.kernel.org, yingjoe.chen@mediatek.com, srv_heupstream@mediatek.com, Daniel Kurtz , Tomasz Figa , eddie.huang@mediatek.com, Matthias Brugger Subject: Re: [PATCH 0/8] iommu: Make core iommu-groups code more generic Message-ID: <20151201151510.GB18805@8bytes.org> References: <1445464303-18206-1-git-send-email-joro@8bytes.org> <1447920801.27650.49.camel@mhfsdcap03> <20151119134114.GC2064@8bytes.org> <1448969391.32066.28.camel@mhfsdcap03> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1448969391.32066.28.camel@mhfsdcap03> 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 Hi Yong Wu, On Tue, Dec 01, 2015 at 07:29:51PM +0800, Yong Wu wrote: > Currently We have to use iommu_detach_group and iommu_attach_group. > Is there any plan for adding detach/attach the device within a iommu > group? No, there is no such plan. The reason is using attach/detach_device always also affects the other devices in the iommu-group. Therefore attach/detach_device was limited to devices which have no others in their group. Having attach/detach_group makes it more obvious to the user that the call affects more than one device. Joerg