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 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 AAFE0C10F11 for ; Wed, 10 Apr 2019 08:46:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 807BC2133D for ; Wed, 10 Apr 2019 08:46:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728809AbfDJIq5 (ORCPT ); Wed, 10 Apr 2019 04:46:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43614 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727196AbfDJIq5 (ORCPT ); Wed, 10 Apr 2019 04:46:57 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A216C58E4B; Wed, 10 Apr 2019 08:46:56 +0000 (UTC) Received: from gondolin (ovpn-204-33.brq.redhat.com [10.40.204.33]) by smtp.corp.redhat.com (Postfix) with ESMTP id 76D085D719; Wed, 10 Apr 2019 08:46:53 +0000 (UTC) Date: Wed, 10 Apr 2019 10:46:49 +0200 From: Cornelia Huck To: Halil Pasic Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, Martin Schwidefsky , Sebastian Ott , virtualization@lists.linux-foundation.org, Christian Borntraeger , Viktor Mihajlovski , Vasily Gorbik , Janosch Frank , Claudio Imbrenda , Farhan Ali , Eric Farman Subject: Re: [RFC PATCH 10/12] virtio/s390: consolidate DMA allocations Message-ID: <20190410104649.12cdbcba.cohuck@redhat.com> In-Reply-To: <20190404231622.52531-11-pasic@linux.ibm.com> References: <20190404231622.52531-1-pasic@linux.ibm.com> <20190404231622.52531-11-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 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Wed, 10 Apr 2019 08:46:56 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, 5 Apr 2019 01:16:20 +0200 Halil Pasic wrote: > We can reduce the number of DMA allocations by pulling the bits > of memory that belongs to virtio_ccw_device and needs to be DMA > memory into a single area. That makes a lot of sense (maybe start with introducing the dma area from the beginning?), but... > > Signed-off-by: Halil Pasic > --- > drivers/s390/virtio/virtio_ccw.c | 48 ++++++++++++++-------------------------- > 1 file changed, 16 insertions(+), 32 deletions(-) > > diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c > index aa45a6a027ae..7268149f2ee8 100644 > --- a/drivers/s390/virtio/virtio_ccw.c > +++ b/drivers/s390/virtio/virtio_ccw.c > @@ -49,12 +49,12 @@ struct vq_config_block { > struct vcdev_dma_area { > unsigned long indicators; > unsigned long indicators2; > + struct vq_config_block config_block; > + __u8 status; /* TODO check __aligned(8); */ ...I think that needs attention. > }; > > struct virtio_ccw_device { > struct virtio_device vdev; > - __u8 *status; > - dma_addr_t status_dma_addr; > __u8 config[VIRTIO_CCW_CONFIG_SIZE]; > struct ccw_device *cdev; > __u32 curr_io;