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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id E46E4C4332F for ; Wed, 8 Nov 2023 05:51:21 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1r0bSW-0004NS-GP; Wed, 08 Nov 2023 00:50:36 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r0bSV-0004NF-GJ for qemu-devel@nongnu.org; Wed, 08 Nov 2023 00:50:35 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r0bST-0006cl-P7 for qemu-devel@nongnu.org; Wed, 08 Nov 2023 00:50:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1699422632; 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=FDKDdLOV2u0CVj0/MYwvUvjyg6dOy8Xhrkpv9Yw8sFk=; b=OiVRYWvNIUzfRDGd8GECEzB+KWWIg6tt+QTtZvCEGxXXkPYRyquhrrywUNNCQlJQH9uJLs eiUDopgvbafP/qY8FGgsIkcdDnKfgBl3QiW8/aQo7mV2cuvOO2WT/yr3tDsf/edLbGwggo FF7FH9+I1NA+dBPEDyK7zUo5Z0BkmeU= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-261-Wb8IN6iOOTWWwGumzrKgmg-1; Wed, 08 Nov 2023 00:50:27 -0500 X-MC-Unique: Wb8IN6iOOTWWwGumzrKgmg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6B80680F8F7; Wed, 8 Nov 2023 05:50:26 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.193.56]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 29AE710F5A; Wed, 8 Nov 2023 05:50:26 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 0926521E6A1F; Wed, 8 Nov 2023 06:50:25 +0100 (CET) From: Markus Armbruster To: =?utf-8?Q?C=C3=A9dric?= Le Goater Cc: Zhenzhong Duan , qemu-devel@nongnu.org, alex.williamson@redhat.com, jgg@nvidia.com, nicolinc@nvidia.com, joao.m.martins@oracle.com, eric.auger@redhat.com, peterx@redhat.com, jasowang@redhat.com, kevin.tian@intel.com, yi.l.liu@intel.com, yi.y.sun@intel.com, chao.p.peng@intel.com, Paolo Bonzini , Eric Blake , Markus Armbruster , Daniel P. =?utf-8?Q?Berrang=C3=A9?= , Eduardo Habkost , Thomas Huth Subject: Re: [PATCH v4 26/41] backends/iommufd: Introduce the iommufd object References: <20231102071302.1818071-1-zhenzhong.duan@intel.com> <20231102071302.1818071-27-zhenzhong.duan@intel.com> Date: Wed, 08 Nov 2023 06:50:25 +0100 In-Reply-To: (=?utf-8?Q?=22C=C3=A9dric?= Le Goater"'s message of "Tue, 7 Nov 2023 14:33:13 +0100") Message-ID: <87r0l0dc9q.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org C=C3=A9dric Le Goater writes: > On 11/2/23 08:12, Zhenzhong Duan wrote: >> From: Eric Auger >> Introduce an iommufd object which allows the interaction >> with the host /dev/iommu device. >> The /dev/iommu can have been already pre-opened outside of qemu, >> in which case the fd can be passed directly along with the >> iommufd object: >> This allows the iommufd object to be shared accross several >> subsystems (VFIO, VDPA, ...). For example, libvirt would open >> the /dev/iommu once. >> If no fd is passed along with the iommufd object, the /dev/iommu >> is opened by the qemu code. >> The CONFIG_IOMMUFD option must be set to compile this new object. >> Suggested-by: Alex Williamson >> Signed-off-by: Eric Auger >> Signed-off-by: Yi Liu >> Signed-off-by: Zhenzhong Duan >> --- >> v4: add CONFIG_IOMMUFD check, document default case >> MAINTAINERS | 7 ++ >> qapi/qom.json | 22 ++++ >> include/sysemu/iommufd.h | 46 +++++++ >> backends/iommufd-stub.c | 59 +++++++++ >> backends/iommufd.c | 257 +++++++++++++++++++++++++++++++++++++++ >> backends/Kconfig | 4 + >> backends/meson.build | 5 + >> backends/trace-events | 12 ++ >> qemu-options.hx | 13 ++ >> 9 files changed, 425 insertions(+) >> create mode 100644 include/sysemu/iommufd.h >> create mode 100644 backends/iommufd-stub.c >> create mode 100644 backends/iommufd.c >> diff --git a/MAINTAINERS b/MAINTAINERS >> index cd8d6b140f..6f35159255 100644 >> --- a/MAINTAINERS >> +++ b/MAINTAINERS >> @@ -2135,6 +2135,13 @@ F: hw/vfio/ap.c >> F: docs/system/s390x/vfio-ap.rst >> L: qemu-s390x@nongnu.org >> +iommufd >> +M: Yi Liu >> +M: Eric Auger >> +S: Supported >> +F: backends/iommufd.c >> +F: include/sysemu/iommufd.h >> + >> vhost >> M: Michael S. Tsirkin >> S: Supported >> diff --git a/qapi/qom.json b/qapi/qom.json >> index c53ef978ff..27300add48 100644 >> --- a/qapi/qom.json >> +++ b/qapi/qom.json >> @@ -794,6 +794,24 @@ >> { 'struct': 'VfioUserServerProperties', >> 'data': { 'socket': 'SocketAddress', 'device': 'str' } } >> +## >> +# @IOMMUFDProperties: >> +# >> +# Properties for iommufd objects. >> +# >> +# @fd: file descriptor name previously passed via 'getfd' command, >> +# which represents a pre-opened /dev/iommu. This allows the >> +# iommufd object to be shared accross several subsystems >> +# (VFIO, VDPA, ...), and the file descriptor to be shared >> +# with other process, e.g. DPDK. (default: QEMU opens >> +# /dev/iommu by itself) >> +# >> +# Since: 8.2 >> +## >> +{ 'struct': 'IOMMUFDProperties', >> + 'data': { '*fd': 'str' }, >> + 'if': 'CONFIG_IOMMUFD' } > > > Activating or not IOMMUFD on a platform is a configuration choice > and it is not a dependency on an external resource. I would make > things simpler and drop all the #ifdef in the documentation files. What exactly are you proposing? The use of 'if': 'CONFIG_IOMMUFD' in the QAPI schema enables introspection with query-qmp-schema: when ObjectType @iommufd exists, QEMU supports creating the object. Or am I confused? > There might be a way to remove the documentation also. Not a big > issue for now. > > >> + >> ## >> # @RngProperties: >> # >> @@ -934,6 +952,8 @@ >> 'input-barrier', >> { 'name': 'input-linux', >> 'if': 'CONFIG_LINUX' }, >> + { 'name': 'iommufd', >> + 'if': 'CONFIG_IOMMUFD' }, >> 'iothread', >> 'main-loop', >> { 'name': 'memory-backend-epc', >> @@ -1003,6 +1023,8 @@ >> 'input-barrier': 'InputBarrierProperties', >> 'input-linux': { 'type': 'InputLinuxProperties', >> 'if': 'CONFIG_LINUX' }, >> + 'iommufd': { 'type': 'IOMMUFDProperties', >> + 'if': 'CONFIG_IOMMUFD' }, >> 'iothread': 'IothreadProperties', >> 'main-loop': 'MainLoopProperties', >> 'memory-backend-epc': { 'type': 'MemoryBackendEpcProperti= es', [...]