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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 99F40C4363D for ; Fri, 2 Oct 2020 17:24:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6232820758 for ; Fri, 2 Oct 2020 17:24:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="MUDIjAzU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726386AbgJBRYt (ORCPT ); Fri, 2 Oct 2020 13:24:49 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:47275 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726096AbgJBRYs (ORCPT ); Fri, 2 Oct 2020 13:24:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1601659486; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Wyu/6NebhFiG1x2CbhG734h8rPbGSszDRSh0XvBsFik=; b=MUDIjAzUL37TdRVzLTrfnuTWtIajiEnONgt4Zd+VrsuvveJxisvkGJFd3oFZbRCn8HsiSo aMQWYVVKb+NRyUXlvuh5Sfl/PElWW+jwJLa/ls8VblzZkCmHP2W6L5sK6/8bi5S4e/gn6v kswj2pdI2ow970gzeEsiSTA1o5UVr78= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-492-_NWWWqabOnGv48SMm1Q4Nw-1; Fri, 02 Oct 2020 13:24:43 -0400 X-MC-Unique: _NWWWqabOnGv48SMm1Q4Nw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0A62D801ABD; Fri, 2 Oct 2020 17:24:42 +0000 (UTC) Received: from x1.home (ovpn-112-71.phx2.redhat.com [10.3.112.71]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7E9EA60CD1; Fri, 2 Oct 2020 17:24:38 +0000 (UTC) Date: Fri, 2 Oct 2020 11:24:37 -0600 From: Alex Williamson To: Diana Craciun Cc: kvm@vger.kernel.org, bharatb.linux@gmail.com, linux-kernel@vger.kernel.org, eric.auger@redhat.com, Bharat Bhushan Subject: Re: [PATCH v5 02/10] vfio/fsl-mc: Scan DPRC objects on vfio-fsl-mc driver bind Message-ID: <20201002112437.0b15a986@x1.home> In-Reply-To: <20200929090339.17659-3-diana.craciun@oss.nxp.com> References: <20200929090339.17659-1-diana.craciun@oss.nxp.com> <20200929090339.17659-3-diana.craciun@oss.nxp.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 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, 29 Sep 2020 12:03:31 +0300 Diana Craciun wrote: > The DPRC (Data Path Resource Container) device is a bus device and has > child devices attached to it. When the vfio-fsl-mc driver is probed > the DPRC is scanned and the child devices discovered and initialized. > > Signed-off-by: Bharat Bhushan > Signed-off-by: Diana Craciun > --- > drivers/vfio/fsl-mc/vfio_fsl_mc.c | 90 +++++++++++++++++++++++ > drivers/vfio/fsl-mc/vfio_fsl_mc_private.h | 1 + > 2 files changed, 91 insertions(+) > > diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c > index a7a483a1e90b..ba44d6d01cc9 100644 > --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c > +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c > @@ -15,6 +15,8 @@ > > #include "vfio_fsl_mc_private.h" > > +static struct fsl_mc_driver vfio_fsl_mc_driver; > + > static int vfio_fsl_mc_open(void *device_data) > { > if (!try_module_get(THIS_MODULE)) > @@ -84,6 +86,79 @@ static const struct vfio_device_ops vfio_fsl_mc_ops = { > .mmap = vfio_fsl_mc_mmap, > }; > > +static int vfio_fsl_mc_bus_notifier(struct notifier_block *nb, > + unsigned long action, void *data) > +{ > + struct vfio_fsl_mc_device *vdev = container_of(nb, > + struct vfio_fsl_mc_device, nb); > + struct device *dev = data; > + struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev); > + struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent); > + > + if (action == BUS_NOTIFY_ADD_DEVICE && > + vdev->mc_dev == mc_cont) { > + mc_dev->driver_override = kasprintf(GFP_KERNEL, "%s", > + vfio_fsl_mc_ops.name); > + if (!mc_dev->driver_override) > + dev_warn(dev, "VFIO_FSL_MC: Setting driver override for device in dprc %s failed\n", > + dev_name(&mc_cont->dev)); > + else > + dev_info(dev, "VFIO_FSL_MC: Setting driver override for device in dprc %s\n", > + dev_name(&mc_cont->dev)); Nit, some whitespace inconsistencies on the second line of each of these. I can fixup on commit if we don't find anything else worth a respin. > + } else if (action == BUS_NOTIFY_BOUND_DRIVER && > + vdev->mc_dev == mc_cont) { > + struct fsl_mc_driver *mc_drv = to_fsl_mc_driver(dev->driver); > + > + if (mc_drv && mc_drv != &vfio_fsl_mc_driver) > + dev_warn(dev, "VFIO_FSL_MC: Object %s bound to driver %s while DPRC bound to vfio-fsl-mc\n", > + dev_name(dev), mc_drv->driver.name); > + } > + > + return 0; > +} > + > +static int vfio_fsl_mc_init_device(struct vfio_fsl_mc_device *vdev) > +{ > + struct fsl_mc_device *mc_dev = vdev->mc_dev; > + int ret; > + > + /* Non-dprc devices share mc_io from parent */ > + if (!is_fsl_mc_bus_dprc(mc_dev)) { > + struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent); > + > + mc_dev->mc_io = mc_cont->mc_io; > + return 0; > + } > + > + vdev->nb.notifier_call = vfio_fsl_mc_bus_notifier; > + ret = bus_register_notifier(&fsl_mc_bus_type, &vdev->nb); > + if (ret) > + return ret; > + > + /* open DPRC, allocate a MC portal */ > + ret = dprc_setup(mc_dev); > + if (ret) { > + dev_err(&mc_dev->dev, "VFIO_FSL_MC: Failed to setup DPRC (%d)\n", ret); > + goto out_nc_unreg; > + } > + > + ret = dprc_scan_container(mc_dev, false); > + if (ret) { > + dev_err(&mc_dev->dev, "VFIO_FSL_MC: Container scanning failed (%d)\n", ret); > + goto out_dprc_cleanup; > + } If I understand this correctly, we've setup the bus notifier to write the driver override as each sub-devices appear on the bus from this scan. When non-dprc devices are removed below, it appears we remove all their sub-devices. Is there a chance here that an error from the scan leaves residual sub-devices, ie. should we proceed the below dprc_cleanup() with a call to dprc_remove_devices() to be certain none remain? Thanks, Alex > + > + return 0; > + > +out_dprc_cleanup: > + dprc_cleanup(mc_dev); > +out_nc_unreg: > + bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb); > + vdev->nb.notifier_call = NULL; > + > + return ret; > +} > + > static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev) > { > struct iommu_group *group; > @@ -110,8 +185,15 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev) > dev_err(dev, "VFIO_FSL_MC: Failed to add to vfio group\n"); > goto out_group_put; > } > + > + ret = vfio_fsl_mc_init_device(vdev); > + if (ret) > + goto out_group_dev; > + > return 0; > > +out_group_dev: > + vfio_del_group_dev(dev); > out_group_put: > vfio_iommu_group_put(group, dev); > return ret; > @@ -126,6 +208,14 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev) > if (!vdev) > return -EINVAL; > > + if (is_fsl_mc_bus_dprc(mc_dev)) { > + dprc_remove_devices(mc_dev, NULL, 0); > + dprc_cleanup(mc_dev); > + } > + > + if (vdev->nb.notifier_call) > + bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb); > + > vfio_iommu_group_put(mc_dev->dev.iommu_group, dev); > > return 0; > diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h > index e79cc116f6b8..37d61eaa58c8 100644 > --- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h > +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h > @@ -9,6 +9,7 @@ > > struct vfio_fsl_mc_device { > struct fsl_mc_device *mc_dev; > + struct notifier_block nb; > }; > > #endif /* VFIO_FSL_MC_PRIVATE_H */