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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 8C8AFC4321A for ; Tue, 11 Jun 2019 10:30:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B5BB206E0 for ; Tue, 11 Jun 2019 10:30:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387593AbfFKKaX (ORCPT ); Tue, 11 Jun 2019 06:30:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42508 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387563AbfFKKaX (ORCPT ); Tue, 11 Jun 2019 06:30:23 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0B0684DB11; Tue, 11 Jun 2019 10:30:18 +0000 (UTC) Received: from gondolin (ovpn-204-147.brq.redhat.com [10.40.204.147]) by smtp.corp.redhat.com (Postfix) with ESMTP id 856D519C70; Tue, 11 Jun 2019 10:30:10 +0000 (UTC) Date: Tue, 11 Jun 2019 12:30:06 +0200 From: Cornelia Huck To: Halil Pasic Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, Sebastian Ott , Heiko Carstens , virtualization@lists.linux-foundation.org, "Michael S. Tsirkin" , Christoph Hellwig , Thomas Huth , Christian Borntraeger , Viktor Mihajlovski , Vasily Gorbik , Janosch Frank , Michael Mueller , Claudio Imbrenda , Farhan Ali , Eric Farman , "Jason J. Herne" Subject: Re: [PATCH v4 7/8] virtio/s390: use DMA memory for ccw I/O and classic notifiers Message-ID: <20190611123006.222aa424.cohuck@redhat.com> In-Reply-To: <20190606115127.55519-8-pasic@linux.ibm.com> References: <20190606115127.55519-1-pasic@linux.ibm.com> <20190606115127.55519-8-pasic@linux.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Tue, 11 Jun 2019 10:30:23 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, 6 Jun 2019 13:51:26 +0200 Halil Pasic wrote: > Before virtio-ccw could get away with not using DMA API for the pieces of > memory it does ccw I/O with. With protected virtualization this has to > change, since the hypervisor needs to read and sometimes also write these > pieces of memory. > > The hypervisor is supposed to poke the classic notifiers, if these are > used, out of band with regards to ccw I/O. So these need to be allocated > as DMA memory (which is shared memory for protected virtualization > guests). > > Let us factor out everything from struct virtio_ccw_device that needs to > be DMA memory in a satellite that is allocated as such. > > Note: The control blocks of I/O instructions do not need to be shared. > These are marshalled by the ultravisor. > > Signed-off-by: Halil Pasic > Reviewed-by: Pierre Morel > --- > drivers/s390/virtio/virtio_ccw.c | 171 ++++++++++++++++--------------- > 1 file changed, 90 insertions(+), 81 deletions(-) (...) > static u64 virtio_ccw_get_features(struct virtio_device *vdev) > { > struct virtio_ccw_device *vcdev = to_vc_device(vdev); > struct virtio_feature_desc *features; > + struct ccw1 *ccw; > int ret; > u64 rc; > - struct ccw1 *ccw; I'd probably not have included unneeded code movement here, but no need to respin for that. > > - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); > + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); > if (!ccw) > return 0; > > - features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL); > + features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features)); > if (!features) { > rc = 0; > goto out_free; (...) Reviewed-by: Cornelia Huck