From patchwork Mon Jul 10 10:07:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13306685 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 7A101C001B0 for ; Mon, 10 Jul 2023 10:08:34 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qIno4-0003xi-AB; Mon, 10 Jul 2023 06:07:48 -0400 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 1qIno2-0003uL-R3 for qemu-devel@nongnu.org; Mon, 10 Jul 2023 06:07:46 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qIno1-0004p6-BB for qemu-devel@nongnu.org; Mon, 10 Jul 2023 06:07:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1688983664; 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=YoxMG4iTkPZLehoWO3OXHc8JLdddwXi1LqzpJbiwRLo=; b=Qv9G2rk0+QUgyX8DJjimHhKpENvoo88HpBOnQtmq/RBLQG90ELtQHcJRu+iqrWN9aoVeG9 Ba929QjLNlkoOd8TcXRznS+/GxaMw9Q7dXEEUUjhYLTS6P/Lql9tY8xjcVTe/psjGA8QPh YeVsx3+RYrlq2Qz2vpEw7M9dJNmL6Ys= 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-650-Zdvh4be_P5Ko-zHMMenzxQ-1; Mon, 10 Jul 2023 06:07:41 -0400 X-MC-Unique: Zdvh4be_P5Ko-zHMMenzxQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 3E437384CC4D; Mon, 10 Jul 2023 10:07:41 +0000 (UTC) Received: from t14s.redhat.com (unknown [10.39.194.160]) by smtp.corp.redhat.com (Postfix) with ESMTP id 23A88111CA03; Mon, 10 Jul 2023 10:07:38 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , Peter Maydell , Paolo Bonzini , Richard Henderson , Eduardo Habkost , "Michael S. Tsirkin" , Marcel Apfelbaum , Igor Mammedov , qemu-arm@nongnu.org, Gavin Shan , Mario Casquero Subject: [PATCH v3 7/7] virtio-mem-pci: Device unplug support Date: Mon, 10 Jul 2023 12:07:14 +0200 Message-ID: <20230710100714.228867-8-david@redhat.com> In-Reply-To: <20230710100714.228867-1-david@redhat.com> References: <20230710100714.228867-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.133.124; envelope-from=david@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=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable 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 Let's support device unplug by forwarding the unplug_request_check() callback to the virtio-mem device. Further, disallow changing the requested-size once an unplug request is pending. Disallowing requested-size changes handles corner cases such as (1) pausing the VM (2) requesting device unplug and (3) adjusting the requested size. If the VM would plug memory (due to the requested size change) before processing the unplug request, we would be in trouble. Signed-off-by: David Hildenbrand --- hw/virtio/virtio-mem-pci.c | 49 +++++++++++++++++++++++++++++++++++--- 1 file changed, 46 insertions(+), 3 deletions(-) diff --git a/hw/virtio/virtio-mem-pci.c b/hw/virtio/virtio-mem-pci.c index 2ef0f07630..c4597e029e 100644 --- a/hw/virtio/virtio-mem-pci.c +++ b/hw/virtio/virtio-mem-pci.c @@ -93,12 +93,53 @@ static void virtio_mem_pci_size_change_notify(Notifier *notifier, void *data) g_free(qom_path); } +static void virtio_mem_pci_unplug_request_check(VirtIOMDPCI *vmd, Error **errp) +{ + VirtIOMEMPCI *pci_mem = VIRTIO_MEM_PCI(vmd); + VirtIOMEM *vmem = &pci_mem->vdev; + VirtIOMEMClass *vpc = VIRTIO_MEM_GET_CLASS(vmem); + + vpc->unplug_request_check(vmem, errp); +} + +static void virtio_mem_pci_get_requested_size(Object *obj, Visitor *v, + const char *name, void *opaque, + Error **errp) +{ + VirtIOMEMPCI *pci_mem = VIRTIO_MEM_PCI(obj); + + object_property_get(OBJECT(&pci_mem->vdev), name, v, errp); +} + +static void virtio_mem_pci_set_requested_size(Object *obj, Visitor *v, + const char *name, void *opaque, + Error **errp) +{ + VirtIOMEMPCI *pci_mem = VIRTIO_MEM_PCI(obj); + DeviceState *dev = DEVICE(obj); + + /* + * If we passed virtio_mem_pci_unplug_request_check(), making sure that + * the requested size is 0, don't allow modifying the requested size + * anymore, otherwise the VM might end up hotplugging memory before + * handling the unplug request. + */ + if (dev->pending_deleted_event) { + error_setg(errp, "'%s' cannot be changed if the device is in the" + " process of unplug", name); + return; + } + + object_property_set(OBJECT(&pci_mem->vdev), name, v, errp); +} + static void virtio_mem_pci_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); VirtioPCIClass *k = VIRTIO_PCI_CLASS(klass); PCIDeviceClass *pcidev_k = PCI_DEVICE_CLASS(klass); MemoryDeviceClass *mdc = MEMORY_DEVICE_CLASS(klass); + VirtIOMDPCIClass *vmdc = VIRTIO_MD_PCI_CLASS(klass); k->realize = virtio_mem_pci_realize; set_bit(DEVICE_CATEGORY_MISC, dc->categories); @@ -111,6 +152,8 @@ static void virtio_mem_pci_class_init(ObjectClass *klass, void *data) mdc->get_memory_region = virtio_mem_pci_get_memory_region; mdc->fill_device_info = virtio_mem_pci_fill_device_info; mdc->get_min_alignment = virtio_mem_pci_get_min_alignment; + + vmdc->unplug_request_check = virtio_mem_pci_unplug_request_check; } static void virtio_mem_pci_instance_init(Object *obj) @@ -135,9 +178,9 @@ static void virtio_mem_pci_instance_init(Object *obj) OBJECT(&dev->vdev), VIRTIO_MEM_BLOCK_SIZE_PROP); object_property_add_alias(obj, VIRTIO_MEM_SIZE_PROP, OBJECT(&dev->vdev), VIRTIO_MEM_SIZE_PROP); - object_property_add_alias(obj, VIRTIO_MEM_REQUESTED_SIZE_PROP, - OBJECT(&dev->vdev), - VIRTIO_MEM_REQUESTED_SIZE_PROP); + object_property_add(obj, VIRTIO_MEM_REQUESTED_SIZE_PROP, "size", + virtio_mem_pci_get_requested_size, + virtio_mem_pci_set_requested_size, NULL, NULL); } static const VirtioPCIDeviceTypeInfo virtio_mem_pci_info = {