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=-6.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=no 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 7CA72C433E2 for ; Tue, 15 Sep 2020 14:56:14 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A5724206E6 for ; Tue, 15 Sep 2020 14:56:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ZBgD4A9c" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A5724206E6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:47214 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kICNQ-0003uI-Ma for qemu-devel@archiver.kernel.org; Tue, 15 Sep 2020 10:56:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35962) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kICMb-0003HA-TE for qemu-devel@nongnu.org; Tue, 15 Sep 2020 10:55:21 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:49000) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kICMY-0005UM-Iu for qemu-devel@nongnu.org; Tue, 15 Sep 2020 10:55:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600181717; 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=2EGm7JY2AcONtMHsj74+sxGbYEEmiFnm21akSM/x7vM=; b=ZBgD4A9cDbURN4VY2VeFvUdx1Xez1uYWVgBiCA3acu40/BQSdNnvhjxrsBNfQ3c4rv9QaD P4oK/qC0FNGib0vQkhr4TVv9rA3VrcMZHJv+JCjRvQ58Q02eAvoQFDdHiqP4/riegr+5Iy /HP9dE0HPgyPrvoszCGp0o+8eTVMJSI= 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-407-BFaPIokdNPWPazhPgb8gIg-1; Tue, 15 Sep 2020 10:55:14 -0400 X-MC-Unique: BFaPIokdNPWPazhPgb8gIg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 065C110AF410; Tue, 15 Sep 2020 14:50:39 +0000 (UTC) Received: from gondolin (ovpn-115-4.ams2.redhat.com [10.36.115.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id C033F78A89; Tue, 15 Sep 2020 14:50:36 +0000 (UTC) Date: Tue, 15 Sep 2020 16:50:33 +0200 From: Cornelia Huck To: Matthew Rosato Subject: Re: [PATCH v2 2/3] s390x/pci: Honor DMA limits set by vfio Message-ID: <20200915165033.1ce30bd2.cohuck@redhat.com> In-Reply-To: <2913a3f4-0c4e-14d2-9d8e-fda75e5defb4@linux.ibm.com> References: <1600122570-12941-1-git-send-email-mjrosato@linux.ibm.com> <1600122570-12941-3-git-send-email-mjrosato@linux.ibm.com> <20200915132849.5e166b3e.cohuck@redhat.com> <2913a3f4-0c4e-14d2-9d8e-fda75e5defb4@linux.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=cohuck@redhat.com X-Mimecast-Spam-Score: 0.002 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=cohuck@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/15 02:10:32 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -50 X-Spam_score: -5.1 X-Spam_bar: ----- X-Spam_report: (-5.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-2.999, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: thuth@redhat.com, pmorel@linux.ibm.com, david@redhat.com, schnelle@linux.ibm.com, qemu-s390x@nongnu.org, qemu-devel@nongnu.org, pasic@linux.ibm.com, borntraeger@de.ibm.com, alex.williamson@redhat.com, rth@twiddle.net Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, 15 Sep 2020 10:16:23 -0400 Matthew Rosato wrote: > On 9/15/20 7:28 AM, Cornelia Huck wrote: > > On Mon, 14 Sep 2020 18:29:29 -0400 > > Matthew Rosato wrote: > > > >> When an s390 guest is using lazy unmapping, it can result in a very > >> large number of oustanding DMA requests, far beyond the default > >> limit configured for vfio. Let's track DMA usage similar to vfio > >> in the host, and trigger the guest to flush their DMA mappings > >> before vfio runs out. > >> > >> Signed-off-by: Matthew Rosato > >> --- > >> hw/s390x/s390-pci-bus.c | 99 +++++++++++++++++++++++++++++++++++++++++++++--- > >> hw/s390x/s390-pci-bus.h | 9 +++++ > >> hw/s390x/s390-pci-inst.c | 29 +++++++++++--- > >> hw/s390x/s390-pci-inst.h | 3 ++ > >> 4 files changed, 129 insertions(+), 11 deletions(-) > >> > > > > (...) > > > >> @@ -737,6 +742,82 @@ static void s390_pci_iommu_free(S390pciState *s, PCIBus *bus, int32_t devfn) > >> object_unref(OBJECT(iommu)); > >> } > >> > >> +static bool s390_sync_dma_avail(int fd, unsigned int *avail) > > > > Not sure I like the name. It sounds like the function checks whether > > "sync dma" is available. Maybe s390_update_dma_avail()? > > > > Sounds fine to me. > > >> +{ > >> + struct vfio_iommu_type1_info *info; > >> + uint32_t argsz; > >> + bool rval = false; > >> + int ret; > >> + > >> + if (avail == NULL) { > >> + return false; > >> + } > >> + > >> + argsz = sizeof(struct vfio_iommu_type1_info); > >> + info = g_malloc0(argsz); > >> + info->argsz = argsz; > >> + /* > >> + * If the specified argsz is not large enough to contain all > >> + * capabilities it will be updated upon return. In this case > >> + * use the updated value to get the entire capability chain. > >> + */ > >> + ret = ioctl(fd, VFIO_IOMMU_GET_INFO, info); > >> + if (argsz != info->argsz) { > >> + argsz = info->argsz; > >> + info = g_realloc(info, argsz); > >> + info->argsz = argsz; > >> + ret = ioctl(fd, VFIO_IOMMU_GET_INFO, info); > >> + } > >> + > >> + if (ret) { > >> + goto out; > >> + } > >> + > >> + /* If the capability exists, update with the current value */ > >> + rval = vfio_get_info_dma_avail(info, avail); > > > > Adding vfio specific things into the generic s390 pci emulation code > > looks a bit ugly... I'd prefer to factor that out into a separate file, > > especially if you plan to add more vfio-specific things in the future. > > > > Fair. hw/s390x/s390-pci-vfio.* ? Sounds good to me.