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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 A6272C4CEC9 for ; Tue, 17 Sep 2019 19:00:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8A9A1214AF for ; Tue, 17 Sep 2019 19:00:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729795AbfIQTAv (ORCPT ); Tue, 17 Sep 2019 15:00:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53760 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729728AbfIQTAv (ORCPT ); Tue, 17 Sep 2019 15:00:51 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5C53AA3D38C; Tue, 17 Sep 2019 19:00:51 +0000 (UTC) Received: from x1.home (ovpn-118-102.phx2.redhat.com [10.3.118.102]) by smtp.corp.redhat.com (Postfix) with ESMTP id 541C160852; Tue, 17 Sep 2019 19:00:45 +0000 (UTC) Date: Tue, 17 Sep 2019 13:00:44 -0600 From: Alex Williamson To: Jason Wang Cc: mst@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kwankhede@nvidia.com, cohuck@redhat.com, tiwei.bie@intel.com, maxime.coquelin@redhat.com, cunming.liang@intel.com, zhihong.wang@intel.com, rob.miller@broadcom.com, idos@mellanox.com, xiao.w.wang@intel.com, haotian.wang@sifive.com Subject: Re: [RFC PATCH 2/4] mdev: introduce helper to set per device dma ops Message-ID: <20190917130044.4fb97637@x1.home> In-Reply-To: <20190910081935.30516-3-jasowang@redhat.com> References: <20190910081935.30516-1-jasowang@redhat.com> <20190910081935.30516-3-jasowang@redhat.com> Organization: Red Hat MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.68]); Tue, 17 Sep 2019 19:00:51 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, 10 Sep 2019 16:19:33 +0800 Jason Wang wrote: > This patch introduces mdev_set_dma_ops() which allows parent to set > per device DMA ops. This help for the kernel driver to setup a correct > DMA mappings. > > Signed-off-by: Jason Wang > --- > drivers/vfio/mdev/mdev_core.c | 7 +++++++ > include/linux/mdev.h | 2 ++ > 2 files changed, 9 insertions(+) > > diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c > index b558d4cfd082..eb28552082d7 100644 > --- a/drivers/vfio/mdev/mdev_core.c > +++ b/drivers/vfio/mdev/mdev_core.c > @@ -13,6 +13,7 @@ > #include > #include > #include > +#include > > #include "mdev_private.h" > > @@ -27,6 +28,12 @@ static struct class_compat *mdev_bus_compat_class; > static LIST_HEAD(mdev_list); > static DEFINE_MUTEX(mdev_list_lock); > > +void mdev_set_dma_ops(struct mdev_device *mdev, struct dma_map_ops *ops) > +{ > + set_dma_ops(&mdev->dev, ops); > +} > +EXPORT_SYMBOL(mdev_set_dma_ops); > + Why does mdev need to be involved here? Your sample driver in 4/4 calls this from its create callback, where it could just as easily call: set_dma_ops(mdev_dev(mdev), ops); Thanks, Alex > struct device *mdev_parent_dev(struct mdev_device *mdev) > { > return mdev->parent->dev; > diff --git a/include/linux/mdev.h b/include/linux/mdev.h > index 0ce30ca78db0..7195f40bf8bf 100644 > --- a/include/linux/mdev.h > +++ b/include/linux/mdev.h > @@ -145,4 +145,6 @@ struct device *mdev_parent_dev(struct mdev_device *mdev); > struct device *mdev_dev(struct mdev_device *mdev); > struct mdev_device *mdev_from_dev(struct device *dev); > > +void mdev_set_dma_ops(struct mdev_device *mdev, struct dma_map_ops *ops); > + > #endif /* MDEV_H */