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=-0.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 4EEBCC04A6B for ; Wed, 8 May 2019 13:18:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2CF9820850 for ; Wed, 8 May 2019 13:18:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728775AbfEHNSV (ORCPT ); Wed, 8 May 2019 09:18:21 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:53652 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727506AbfEHNSU (ORCPT ); Wed, 8 May 2019 09:18:20 -0400 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x48DGhgO064489 for ; Wed, 8 May 2019 09:18:19 -0400 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0a-001b2d01.pphosted.com with ESMTP id 2sby19jtkr-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 08 May 2019 09:18:18 -0400 Received: from localhost by e06smtp07.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Wed, 8 May 2019 14:18:13 +0100 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x48DIBm448955618 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 8 May 2019 13:18:11 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6C1EEA4057; Wed, 8 May 2019 13:18:11 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C6BAEA405B; Wed, 8 May 2019 13:18:10 +0000 (GMT) Received: from dyn-9-152-212-30.boeblingen.de.ibm.com (unknown [9.152.212.30]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Wed, 8 May 2019 13:18:10 +0000 (GMT) Date: Wed, 8 May 2019 15:18:10 +0200 (CEST) From: Sebastian Ott X-X-Sender: sebott@schleppi To: Halil Pasic cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, Cornelia Huck , Martin Schwidefsky , virtualization@lists.linux-foundation.org, "Michael S. Tsirkin" , Christoph Hellwig , Thomas Huth , Christian Borntraeger , Viktor Mihajlovski , Vasily Gorbik , Janosch Frank , Claudio Imbrenda , Farhan Ali , Eric Farman Subject: Re: [PATCH 05/10] s390/cio: introduce DMA pools to cio In-Reply-To: <20190426183245.37939-6-pasic@linux.ibm.com> References: <20190426183245.37939-1-pasic@linux.ibm.com> <20190426183245.37939-6-pasic@linux.ibm.com> User-Agent: Alpine 2.21 (LFD 202 2017-01-01) Organization: =?ISO-8859-15?Q?=22IBM_Deutschland_Research_&_Development_GmbH?= =?ISO-8859-15?Q?_=2F_Vorsitzende_des_Aufsichtsrats=3A_Matthias?= =?ISO-8859-15?Q?_Hartmann_Gesch=E4ftsf=FChrung=3A_Dirk_Wittkopp?= =?ISO-8859-15?Q?_Sitz_der_Gesellschaft=3A_B=F6blingen_=2F_Reg?= =?ISO-8859-15?Q?istergericht=3A_Amtsgericht_Stuttgart=2C_HRB_2432?= =?ISO-8859-15?Q?94=22?= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-TM-AS-GCONF: 00 x-cbid: 19050813-0028-0000-0000-0000036B90E7 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19050813-0029-0000-0000-0000242B0E18 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-05-08_07:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=11 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=860 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905080085 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, 26 Apr 2019, Halil Pasic wrote: > @@ -224,6 +228,9 @@ struct subchannel *css_alloc_subchannel(struct subchannel_id schid, > INIT_WORK(&sch->todo_work, css_sch_todo); > sch->dev.release = &css_subchannel_release; > device_initialize(&sch->dev); > + sch->dma_mask = css_dev_dma_mask; > + sch->dev.dma_mask = &sch->dma_mask; > + sch->dev.coherent_dma_mask = sch->dma_mask; Could we do: sch->dev.dma_mask = &sch->dev.coherent_dma_mask; sch->dev.coherent_dma_mask = css_dev_dma_mask; ? > +#define POOL_INIT_PAGES 1 > +static struct gen_pool *cio_dma_pool; > +/* Currently cio supports only a single css */ > +#define CIO_DMA_GFP (GFP_KERNEL | __GFP_ZERO) __GFP_ZERO has no meaning with the dma api (since all implementations do an implicit zero initialization) but let's keep it for the sake of documentation. We need GFP_DMA here (which will return addresses < 2G on s390)! > +void cio_gp_dma_free(struct gen_pool *gp_dma, void *cpu_addr, size_t size) > +{ > + if (!cpu_addr) > + return; > + memset(cpu_addr, 0, size); Hm, normally I'd do the memset during alloc not during free - but maybe this makes more sense here with your usecase in mind. > @@ -1063,6 +1163,7 @@ static int __init css_bus_init(void) > unregister_reboot_notifier(&css_reboot_notifier); > goto out_unregister; > } > + cio_dma_pool_init(); This is too late for early devices (ccw console!).