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 8B2BFC43334 for ; Wed, 15 Jun 2022 15:58:13 +0000 (UTC) Received: from localhost ([::1]:48018 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1o1VPI-0002CY-GK for qemu-devel@archiver.kernel.org; Wed, 15 Jun 2022 11:58:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43006) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1o1VLe-0003qL-SI for qemu-devel@nongnu.org; Wed, 15 Jun 2022 11:54:26 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:41482) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1o1VLa-0007H8-89 for qemu-devel@nongnu.org; Wed, 15 Jun 2022 11:54:26 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1655308461; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=E/Xes3Sx/m22LuAiH/kQPVPos8EAj3hA5tpXxXIp8pM=; b=Lp8tWWe1rNN6wu06waLidls4BWczj/dkCza+eXbN3KIGTTfzHDtNvhAUa4U4TttKq+rrS+ nVPloZdlgePwgNjz+mdqPEHey7s7liSHEDRAUfXHn0cSlchUlPvth656K58WctGjGQ+3cg MsOnBpKhhLvCLE11T4GGUrqVDxAGuDo= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-620-N2rf4UvuMiuAovityDAxXA-1; Wed, 15 Jun 2022 11:54:18 -0400 X-MC-Unique: N2rf4UvuMiuAovityDAxXA-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E789538005C9; Wed, 15 Jun 2022 15:54:17 +0000 (UTC) Received: from localhost (unknown [10.39.192.100]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6AF93492C3B; Wed, 15 Jun 2022 15:54:17 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Thomas Huth , Jagannathan Raman , Aarushi Mehta , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Elena Ufimtseva , Marcel Apfelbaum , Stefan Hajnoczi , Laurent Vivier , , "Dr. David Alan Gilbert" , Richard Henderson , virtio-fs@redhat.com, Hanna Reitz , David Hildenbrand , =?UTF-8?q?Alex=20Benn=C3=A9e?= , Eric Blake , Kevin Wolf , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= , Beraldo Leal , Peter Xu , Eduardo Habkost , Qiuhao Li , Paolo Bonzini , Markus Armbruster , Bandan Das , "Michael S. Tsirkin" , Stefano Garzarella , Alexander Bulekov , Julia Suvorova , Darren Kenny , Wainer dos Santos Moschetta , John G Johnson Subject: [PULL 03/18] qdev: unplug blocker for devices Date: Wed, 15 Jun 2022 16:51:14 +0100 Message-Id: <20220615155129.1025811-4-stefanha@redhat.com> In-Reply-To: <20220615155129.1025811-1-stefanha@redhat.com> References: <20220615155129.1025811-1-stefanha@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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" From: Jagannathan Raman Add blocker to prevent hot-unplug of devices TYPE_VFIO_USER_SERVER, which is introduced shortly, attaches itself to a PCIDevice on which it depends. If the attached PCIDevice gets removed while the server in use, it could cause it crash. To prevent this, TYPE_VFIO_USER_SERVER adds an unplug blocker for the PCIDevice. Signed-off-by: Elena Ufimtseva Signed-off-by: John G Johnson Signed-off-by: Jagannathan Raman Reviewed-by: Stefan Hajnoczi Message-id: c41ef80b7cc063314d629737bed2159e5713f2e0.1655151679.git.jag.raman@oracle.com Signed-off-by: Stefan Hajnoczi --- include/hw/qdev-core.h | 29 +++++++++++++++++++++++++++++ hw/core/qdev.c | 24 ++++++++++++++++++++++++ softmmu/qdev-monitor.c | 4 ++++ 3 files changed, 57 insertions(+) diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h index 92c3d65208..98774e2835 100644 --- a/include/hw/qdev-core.h +++ b/include/hw/qdev-core.h @@ -193,6 +193,7 @@ struct DeviceState { int instance_id_alias; int alias_required_for_version; ResettableState reset; + GSList *unplug_blockers; }; struct DeviceListener { @@ -419,6 +420,34 @@ void qdev_simple_device_unplug_cb(HotplugHandler *hotplug_dev, void qdev_machine_creation_done(void); bool qdev_machine_modified(void); +/** + * qdev_add_unplug_blocker: Add an unplug blocker to a device + * + * @dev: Device to be blocked from unplug + * @reason: Reason for blocking + */ +void qdev_add_unplug_blocker(DeviceState *dev, Error *reason); + +/** + * qdev_del_unplug_blocker: Remove an unplug blocker from a device + * + * @dev: Device to be unblocked + * @reason: Pointer to the Error used with qdev_add_unplug_blocker. + * Used as a handle to lookup the blocker for deletion. + */ +void qdev_del_unplug_blocker(DeviceState *dev, Error *reason); + +/** + * qdev_unplug_blocked: Confirm if a device is blocked from unplug + * + * @dev: Device to be tested + * @reason: Returns one of the reasons why the device is blocked, + * if any + * + * Returns: true if device is blocked from unplug, false otherwise + */ +bool qdev_unplug_blocked(DeviceState *dev, Error **errp); + /** * GpioPolarity: Polarity of a GPIO line * diff --git a/hw/core/qdev.c b/hw/core/qdev.c index 84f3019440..0806d8fcaa 100644 --- a/hw/core/qdev.c +++ b/hw/core/qdev.c @@ -468,6 +468,28 @@ char *qdev_get_dev_path(DeviceState *dev) return NULL; } +void qdev_add_unplug_blocker(DeviceState *dev, Error *reason) +{ + dev->unplug_blockers = g_slist_prepend(dev->unplug_blockers, reason); +} + +void qdev_del_unplug_blocker(DeviceState *dev, Error *reason) +{ + dev->unplug_blockers = g_slist_remove(dev->unplug_blockers, reason); +} + +bool qdev_unplug_blocked(DeviceState *dev, Error **errp) +{ + ERRP_GUARD(); + + if (dev->unplug_blockers) { + error_propagate(errp, error_copy(dev->unplug_blockers->data)); + return true; + } + + return false; +} + static bool device_get_realized(Object *obj, Error **errp) { DeviceState *dev = DEVICE(obj); @@ -704,6 +726,8 @@ static void device_finalize(Object *obj) DeviceState *dev = DEVICE(obj); + g_assert(!dev->unplug_blockers); + QLIST_FOREACH_SAFE(ngl, &dev->gpios, node, next) { QLIST_REMOVE(ngl, node); qemu_free_irqs(ngl->in, ngl->num_in); diff --git a/softmmu/qdev-monitor.c b/softmmu/qdev-monitor.c index bb5897fc76..4b0ef65780 100644 --- a/softmmu/qdev-monitor.c +++ b/softmmu/qdev-monitor.c @@ -899,6 +899,10 @@ void qdev_unplug(DeviceState *dev, Error **errp) HotplugHandlerClass *hdc; Error *local_err = NULL; + if (qdev_unplug_blocked(dev, errp)) { + return; + } + if (dev->parent_bus && !qbus_is_hotpluggable(dev->parent_bus)) { error_setg(errp, QERR_BUS_NO_HOTPLUG, dev->parent_bus->name); return; -- 2.36.1