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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC3DFC433FE for ; Fri, 27 May 2022 06:02:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243854AbiE0GCu (ORCPT ); Fri, 27 May 2022 02:02:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39762 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244056AbiE0GCt (ORCPT ); Fri, 27 May 2022 02:02:49 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 42D40FD4 for ; Thu, 26 May 2022 23:02:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1653631360; 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=0C6hcQ5Jjv81qlifMWaFIwQcLt5pTYV5jL+U8XNNh0g=; b=ZiY3AXOzC/sGr0SbYIh1MEQBxiJTgGs0s9Fzy9qiFoysrKYbLyhXC6I0hNcXVOu3trdCHc viPR2DEofv2gsClyjzhTBC6riLJYmZsnZz37bQqrhOdVZuzIwGmEo3sB5qHKP5yuEuq8XF 2SJTPkjrFXucLOVq6mSxAw5DtBJIr2A= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-640-9J-8aTfMME68fJLEUeCfHQ-1; Fri, 27 May 2022 02:02:36 -0400 X-MC-Unique: 9J-8aTfMME68fJLEUeCfHQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 974C3803B22; Fri, 27 May 2022 06:02:35 +0000 (UTC) Received: from localhost.localdomain (ovpn-13-240.pek2.redhat.com [10.72.13.240]) by smtp.corp.redhat.com (Postfix) with ESMTP id 70C8D2166B26; Fri, 27 May 2022 06:02:26 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org Cc: tglx@linutronix.de, peterz@infradead.org, paulmck@kernel.org, maz@kernel.org, pasic@linux.ibm.com, cohuck@redhat.com, eperezma@redhat.com, lulu@redhat.com, sgarzare@redhat.com, xuanzhuo@linux.alibaba.com, Vineeth Vijayan , Peter Oberparleiter , linux-s390@vger.kernel.org Subject: [PATCH V6 7/9] virtio: allow to unbreak virtqueue Date: Fri, 27 May 2022 14:01:18 +0800 Message-Id: <20220527060120.20964-8-jasowang@redhat.com> In-Reply-To: <20220527060120.20964-1-jasowang@redhat.com> References: <20220527060120.20964-1-jasowang@redhat.com> MIME-Version: 1.0 Content-type: text/plain Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org This patch allows the new introduced __virtio_break_device() to unbreak the virtqueue. Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: "Paul E. McKenney" Cc: Marc Zyngier Cc: Halil Pasic Cc: Cornelia Huck Cc: Vineeth Vijayan Cc: Peter Oberparleiter Cc: linux-s390@vger.kernel.org Signed-off-by: Jason Wang --- drivers/virtio/virtio_ring.c | 22 ++++++++++++++++++++++ include/linux/virtio.h | 1 + 2 files changed, 23 insertions(+) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 9d0bae4293be..9c231e1fded7 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2395,6 +2395,28 @@ void virtio_break_device(struct virtio_device *dev) } EXPORT_SYMBOL_GPL(virtio_break_device); +/* + * This should allow the device to be used by the driver. You may + * need to grab appropriate locks to flush the write to + * vq->broken. This should only be used in some specific case e.g + * (probing and restoring). This function should only be called by the + * core, not directly by the driver. + */ +void __virtio_unbreak_device(struct virtio_device *dev) +{ + struct virtqueue *_vq; + + spin_lock(&dev->vqs_list_lock); + list_for_each_entry(_vq, &dev->vqs, list) { + struct vring_virtqueue *vq = to_vvq(_vq); + + /* Pairs with READ_ONCE() in virtqueue_is_broken(). */ + WRITE_ONCE(vq->broken, false); + } + spin_unlock(&dev->vqs_list_lock); +} +EXPORT_SYMBOL_GPL(__virtio_unbreak_device); + dma_addr_t virtqueue_get_desc_addr(struct virtqueue *_vq) { struct vring_virtqueue *vq = to_vvq(_vq); diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 5464f398912a..d8fdf170637c 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -131,6 +131,7 @@ void unregister_virtio_device(struct virtio_device *dev); bool is_virtio_device(struct device *dev); void virtio_break_device(struct virtio_device *dev); +void __virtio_unbreak_device(struct virtio_device *dev); void virtio_config_changed(struct virtio_device *dev); #ifdef CONFIG_PM_SLEEP -- 2.25.1