From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 56902C04EB9 for ; Wed, 5 Dec 2018 17:17:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 292EC2082B for ; Wed, 5 Dec 2018 17:17:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 292EC2082B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728006AbeLERR5 (ORCPT ); Wed, 5 Dec 2018 12:17:57 -0500 Received: from foss.arm.com ([217.140.101.70]:59490 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727772AbeLERR4 (ORCPT ); Wed, 5 Dec 2018 12:17:56 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5305CA78; Wed, 5 Dec 2018 09:17:56 -0800 (PST) Received: from [10.1.196.75] (e110467-lin.cambridge.arm.com [10.1.196.75]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 667DE3F575; Wed, 5 Dec 2018 09:17:55 -0800 (PST) Subject: Re: [PATCH 2/5] iommu/of: Use device_iommu_mapped() To: Joerg Roedel , iommu@lists.linux-foundation.org, Greg Kroah-Hartman Cc: Joerg Roedel , linux-kernel@vger.kernel.org References: <20181204172504.19708-1-joro@8bytes.org> <20181204172504.19708-3-joro@8bytes.org> From: Robin Murphy Message-ID: <44c82503-bc36-e8de-6932-7c4fd2b597f8@arm.com> Date: Wed, 5 Dec 2018 17:17:54 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20181204172504.19708-3-joro@8bytes.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/12/2018 17:25, Joerg Roedel wrote: > From: Joerg Roedel > > Use Use device_iommu_mapped() to check if the device is > already mapped by an IOMMU. FWIW, this check (and its ACPI equivalent in patch #3) is specifically asking "has .add_device() already been called?", rather than the more general "is this device managed by an IOMMU?" (to which the exact answer at this point is "yes, provided we return successfully from here"). I have no objection to the change as-is - especially if that usage is within the intended scope of this API - I just wanted to call it out in case you're also planning to introduce something else which would be even more appropriate for that. Robin. > Signed-off-by: Joerg Roedel > --- > drivers/iommu/of_iommu.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c > index c5dd63072529..bfcf139503f0 100644 > --- a/drivers/iommu/of_iommu.c > +++ b/drivers/iommu/of_iommu.c > @@ -220,7 +220,7 @@ const struct iommu_ops *of_iommu_configure(struct device *dev, > * If we have reason to believe the IOMMU driver missed the initial > * add_device callback for dev, replay it to get things in order. > */ > - if (ops && ops->add_device && dev->bus && !dev->iommu_group) > + if (ops && ops->add_device && dev->bus && !device_iommu_mapped(dev)) > err = ops->add_device(dev); > > /* Ignore all other errors apart from EPROBE_DEFER */ >