From nobody Sun Feb 8 00:50:25 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1498676866513942.2917269436958; Wed, 28 Jun 2017 12:07:46 -0700 (PDT) Received: from localhost ([::1]:35270 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dQIJQ-0001Mc-Uu for importer@patchew.org; Wed, 28 Jun 2017 15:07:40 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40428) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dQIDj-0004cz-DH for qemu-devel@nongnu.org; Wed, 28 Jun 2017 15:01:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dQIDi-0008Al-3n for qemu-devel@nongnu.org; Wed, 28 Jun 2017 15:01:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43112) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dQIDh-0008AF-Tq for qemu-devel@nongnu.org; Wed, 28 Jun 2017 15:01:46 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id C51BAC04B31E; Wed, 28 Jun 2017 19:01:44 +0000 (UTC) Received: from dgilbert-t530.redhat.com (ovpn-117-210.ams2.redhat.com [10.36.117.210]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6EEE817D32; Wed, 28 Jun 2017 19:01:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com C51BAC04B31E Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=dgilbert@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com C51BAC04B31E From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, a.perevalov@samsung.com, marcandre.lureau@redhat.com, maxime.coquelin@redhat.com, mst@redhat.com, quintela@redhat.com, peterx@redhat.com, lvivier@redhat.com, aarcange@redhat.com Date: Wed, 28 Jun 2017 20:00:28 +0100 Message-Id: <20170628190047.26159-11-dgilbert@redhat.com> In-Reply-To: <20170628190047.26159-1-dgilbert@redhat.com> References: <20170628190047.26159-1-dgilbert@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Wed, 28 Jun 2017 19:01:44 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [RFC 10/29] vhub: Open userfaultfd X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: "Dr. David Alan Gilbert" Open a userfaultfd (on a postcopy_advise) and send it back in the reply to the qemu for it to monitor. Signed-off-by: Dr. David Alan Gilbert --- contrib/libvhost-user/libvhost-user.c | 24 +++++++++++++++++++++--- contrib/libvhost-user/libvhost-user.h | 3 +++ 2 files changed, 24 insertions(+), 3 deletions(-) diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/= libvhost-user.c index e3a32755cf..62e97f6b84 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -15,6 +15,7 @@ =20 #include #include +#include #include =20 #include "qemu/atomic.h" @@ -774,11 +775,28 @@ vu_set_vring_enable_exec(VuDev *dev, VhostUserMsg *vm= sg) static bool vu_set_postcopy_advise(VuDev *dev, VhostUserMsg *vmsg) { - /* TODO: Open ufd, pass it back in the request - /* TODO: Add addresses=20 - */ + struct uffdio_api api_struct; + + dev->postcopy_ufd =3D syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK= ); + /* TODO: Add addresses */ vmsg->payload.u64 =3D 0xcafe; vmsg->size =3D sizeof(vmsg->payload.u64); + + if (dev->postcopy_ufd =3D=3D -1) { + vu_panic(dev, "Userfaultfd not available: %s", strerror(errno)); + return false; + } + api_struct.api =3D UFFD_API; + api_struct.features =3D 0; + if (ioctl(dev->postcopy_ufd, UFFDIO_API, &api_struct)) { + vu_panic(dev, "Failed UFFDIO_API: %s", strerror(errno)); + close(dev->postcopy_ufd); + return false; + } + /* TODO: Stash feature flags somewhere */ + /* Return a ufd to the QEMU */ + vmsg->fd_num =3D 1; + vmsg->fds[0] =3D dev->postcopy_ufd; return true; /* =3D send a reply */ } =20 diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/= libvhost-user.h index 8bb35582ea..3e65a962da 100644 --- a/contrib/libvhost-user/libvhost-user.h +++ b/contrib/libvhost-user/libvhost-user.h @@ -231,6 +231,9 @@ struct VuDev { * re-initialize */ vu_panic_cb panic; const VuDevIface *iface; + + /* Postcopy data */ + int postcopy_ufd; }; =20 typedef struct VuVirtqElement { --=20 2.13.0