From patchwork Wed Oct 23 08:27:01 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Freimann X-Patchwork-Id: 1181898 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="QCVnNoUw"; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 46yk7b2fZwz9sPl for ; Wed, 23 Oct 2019 19:29:31 +1100 (AEDT) Received: from localhost ([::1]:57202 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNC1J-0002wT-0A for incoming@patchwork.ozlabs.org; Wed, 23 Oct 2019 04:29:29 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48284) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNBze-0002v9-90 for qemu-devel@nongnu.org; Wed, 23 Oct 2019 04:27:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iNBzb-0005te-LG for qemu-devel@nongnu.org; Wed, 23 Oct 2019 04:27:46 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:37896 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iNBzS-0005mp-Ge for qemu-devel@nongnu.org; Wed, 23 Oct 2019 04:27:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1571819253; 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=N1mXYBWjlIW+rCQl00usBp8V13DJOB43c4Zk4huMvtw=; b=QCVnNoUw6dzHUOPdtjk1i16wr6sYGmxH0YPogxLfxGBRNI/RSW1XfiKZLOKBFCC4qOzVVk 2t9AuRN6tLtPc9+rJ+AuS90gX6lrXpo0wRAJBIIok+i9EQGVPgnwgvc/ACqH4PxsvginS2 bDq/ep9ad+v8e5ibFpUg8D6NMhGh8VA= 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-155-ofTJ5aN6Ormn2l3eygDQRw-1; Wed, 23 Oct 2019 04:27:30 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 922221800E01; Wed, 23 Oct 2019 08:27:29 +0000 (UTC) Received: from localhost (dhcp-192-217.str.redhat.com [10.33.192.217]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B9E2B60628; Wed, 23 Oct 2019 08:27:21 +0000 (UTC) From: Jens Freimann To: qemu-devel@nongnu.org Subject: [PATCH v5 01/11] qdev/qbus: add hidden device support Date: Wed, 23 Oct 2019 10:27:01 +0200 Message-Id: <20191023082711.16694-2-jfreimann@redhat.com> In-Reply-To: <20191023082711.16694-1-jfreimann@redhat.com> References: <20191023082711.16694-1-jfreimann@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-MC-Unique: ofTJ5aN6Ormn2l3eygDQRw-1 X-Mimecast-Spam-Score: 0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 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: pkrempa@redhat.com, berrange@redhat.com, ehabkost@redhat.com, mst@redhat.com, aadam@redhat.com, dgilbert@redhat.com, alex.williamson@redhat.com, laine@redhat.com, ailan@redhat.com, parav@mellanox.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" This adds support for hiding a device to the qbus and qdev APIs. The first user of this will be the virtio-net failover feature but the API introduced with this patch could be used to implement other features as well, for example hiding pci devices when a pci bus is powered off. qdev_device_add() is modified to check for a net_failover_pair_id argument in the option string. A DeviceListener callback should_be_hidden() is added. It can be used by a standby device to inform qdev that this device should not be added now. The standby device handler can store the device options to plug the device in at a later point in time. One reason for hiding the device is that we don't want to expose both devices to the guest kernel until the respective virtio feature bit VIRTIO_NET_F_STANDBY was negotiated and we know that the devices will be handled correctly by the guest. More information on the kernel feature this is using: https://www.kernel.org/doc/html/latest/networking/net_failover.html An example where the primary device is a vfio-pci device and the standby device is a virtio-net device: A device is hidden when it has an "net_failover_pair_id" option, e.g. -device virtio-net-pci,...,failover=on,... -device vfio-pci,...,net_failover_pair_id=net1,... Signed-off-by: Jens Freimann Reviewed-by: Cornelia Huck --- hw/core/qdev.c | 23 +++++++++++++++++++++++ include/hw/qdev-core.h | 29 +++++++++++++++++++++++++++++ qdev-monitor.c | 41 +++++++++++++++++++++++++++++++++++++---- vl.c | 6 ++++-- 4 files changed, 93 insertions(+), 6 deletions(-) diff --git a/hw/core/qdev.c b/hw/core/qdev.c index cbad6c1d55..f786650446 100644 --- a/hw/core/qdev.c +++ b/hw/core/qdev.c @@ -212,6 +212,29 @@ void device_listener_unregister(DeviceListener *listener) QTAILQ_REMOVE(&device_listeners, listener, link); } +bool qdev_should_hide_device(QemuOpts *opts) +{ + int rc = -1; + DeviceListener *listener; + + QTAILQ_FOREACH(listener, &device_listeners, link) { + if (listener->should_be_hidden) { + /* should_be_hidden_will return + * 1 if device matches opts and it should be hidden + * 0 if device matches opts and should not be hidden + * -1 if device doesn't match opts + */ + rc = listener->should_be_hidden(listener, opts); + } + + if (rc > 0) { + break; + } + } + + return rc > 0; +} + void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id, int required_for_version) { diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h index aa123f88cb..710981af36 100644 --- a/include/hw/qdev-core.h +++ b/include/hw/qdev-core.h @@ -78,6 +78,19 @@ typedef void (*BusUnrealize)(BusState *bus, Error **errp); * respective parent types. * * + * + * # Hiding a device # + * To hide a device, a DeviceListener function should_be_hidden() needs to + * be registered. + * It can be used to defer adding a device and therefore hide it from the + * guest. The handler registering to this DeviceListener can save the QOpts + * passed to it for re-using it later and must return that it wants the device + * to be/remain hidden or not. When the handler function decides the device + * shall not be hidden it will be added in qdev_device_add() and + * realized as any other device. Otherwise qdev_device_add() will return early + * without adding the device. The guest will not see a "hidden" device + * until it was marked don't hide and qdev_device_add called again. + * */ typedef struct DeviceClass { /*< private >*/ @@ -154,6 +167,12 @@ struct DeviceState { struct DeviceListener { void (*realize)(DeviceListener *listener, DeviceState *dev); void (*unrealize)(DeviceListener *listener, DeviceState *dev); + /* + * This callback is called upon init of the DeviceState and allows to + * inform qdev that a device should be hidden, depending on the device + * opts, for example, to hide a standby device. + */ + int (*should_be_hidden)(DeviceListener *listener, QemuOpts *device_opts); QTAILQ_ENTRY(DeviceListener) link; }; @@ -451,4 +470,14 @@ static inline bool qbus_is_hotpluggable(BusState *bus) void device_listener_register(DeviceListener *listener); void device_listener_unregister(DeviceListener *listener); +/** + * @qdev_should_hide_device: + * @opts: QemuOpts as passed on cmdline. + * + * Check if a device should be added. + * When a device is added via qdev_device_add() this will be called, + * and return if the device should be added now or not. + */ +bool qdev_should_hide_device(QemuOpts *opts); + #endif diff --git a/qdev-monitor.c b/qdev-monitor.c index 148df9cacf..676a759fb4 100644 --- a/qdev-monitor.c +++ b/qdev-monitor.c @@ -32,9 +32,11 @@ #include "qemu/help_option.h" #include "qemu/option.h" #include "qemu/qemu-print.h" +#include "qemu/option_int.h" #include "sysemu/block-backend.h" #include "sysemu/sysemu.h" #include "migration/misc.h" +#include "migration/migration.h" /* * Aliases were a bad idea from the start. Let's keep them @@ -562,13 +564,36 @@ void qdev_set_id(DeviceState *dev, const char *id) } } +static int is_failover_device(void *opaque, const char *name, const char *value, + Error **errp) +{ + if (strcmp(name, "net_failover_pair_id") == 0) { + QemuOpts *opts = (QemuOpts *)opaque; + + if (qdev_should_hide_device(opts)) { + return 1; + } + } + + return 0; +} + +static bool should_hide_device(QemuOpts *opts) +{ + if (qemu_opt_foreach(opts, is_failover_device, opts, NULL) == 0) { + return false; + } + return true; +} + DeviceState *qdev_device_add(QemuOpts *opts, Error **errp) { DeviceClass *dc; const char *driver, *path; - DeviceState *dev; + DeviceState *dev = NULL; BusState *bus = NULL; Error *err = NULL; + bool hide; driver = qemu_opt_get(opts, "driver"); if (!driver) { @@ -602,11 +627,17 @@ DeviceState *qdev_device_add(QemuOpts *opts, Error **errp) return NULL; } } - if (qdev_hotplug && bus && !qbus_is_hotpluggable(bus)) { + hide = should_hide_device(opts); + + if ((hide || qdev_hotplug) && bus && !qbus_is_hotpluggable(bus)) { error_setg(errp, QERR_BUS_NO_HOTPLUG, bus->name); return NULL; } + if (hide) { + return NULL; + } + if (!migration_is_idle()) { error_setg(errp, "device_add not allowed while migrating"); return NULL; @@ -648,8 +679,10 @@ DeviceState *qdev_device_add(QemuOpts *opts, Error **errp) err_del_dev: error_propagate(errp, err); - object_unparent(OBJECT(dev)); - object_unref(OBJECT(dev)); + if (dev) { + object_unparent(OBJECT(dev)); + object_unref(OBJECT(dev)); + } return NULL; } diff --git a/vl.c b/vl.c index 4489cfb2bb..62c388cb49 100644 --- a/vl.c +++ b/vl.c @@ -2204,10 +2204,12 @@ static int device_init_func(void *opaque, QemuOpts *opts, Error **errp) DeviceState *dev; dev = qdev_device_add(opts, errp); - if (!dev) { + if (!dev && *errp) { + error_report_err(*errp); return -1; + } else if (dev) { + object_unref(OBJECT(dev)); } - object_unref(OBJECT(dev)); return 0; }