From patchwork Wed Jun 29 06:56:37 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xuan Zhuo X-Patchwork-Id: 12899448 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 ADCC8CCA47F for ; Wed, 29 Jun 2022 06:59:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232761AbiF2G7E (ORCPT ); Wed, 29 Jun 2022 02:59:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38686 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231987AbiF2G6T (ORCPT ); Wed, 29 Jun 2022 02:58:19 -0400 Received: from out30-43.freemail.mail.aliyun.com (out30-43.freemail.mail.aliyun.com [115.124.30.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6859326C2; Tue, 28 Jun 2022 23:57:48 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R181e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045170;MF=xuanzhuo@linux.alibaba.com;NM=1;PH=DS;RN=37;SR=0;TI=SMTPD_---0VHmY1MN_1656485861; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VHmY1MN_1656485861) by smtp.aliyun-inc.com; Wed, 29 Jun 2022 14:57:42 +0800 From: Xuan Zhuo To: virtualization@lists.linux-foundation.org Cc: Richard Weinberger , Anton Ivanov , Johannes Berg , "Michael S. Tsirkin" , Jason Wang , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Hans de Goede , Mark Gross , Vadim Pasternak , Bjorn Andersson , Mathieu Poirier , Cornelia Huck , Halil Pasic , Eric Farman , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Xuan Zhuo , Vincent Whitchurch , linux-um@lists.infradead.org, netdev@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-remoteproc@vger.kernel.org, linux-s390@vger.kernel.org, kvm@vger.kernel.org, bpf@vger.kernel.org, kangjie.xu@linux.alibaba.com Subject: [PATCH v11 21/40] virtio_ring: packed: introduce virtqueue_resize_packed() Date: Wed, 29 Jun 2022 14:56:37 +0800 Message-Id: <20220629065656.54420-22-xuanzhuo@linux.alibaba.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20220629065656.54420-1-xuanzhuo@linux.alibaba.com> References: <20220629065656.54420-1-xuanzhuo@linux.alibaba.com> MIME-Version: 1.0 X-Git-Hash: 3fdaf102dd89 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org virtio ring packed supports resize. Only after the new vring is successfully allocated based on the new num, we will release the old vring. In any case, an error is returned, indicating that the vring still points to the old vring. In the case of an error, re-initialize(by virtqueue_reinit_packed()) the virtqueue to ensure that the vring can be used. Signed-off-by: Xuan Zhuo Acked-by: Jason Wang --- drivers/virtio/virtio_ring.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 650f701a5480..4860787286db 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2042,6 +2042,35 @@ static struct virtqueue *vring_create_virtqueue_packed( return NULL; } +static int virtqueue_resize_packed(struct virtqueue *_vq, u32 num) +{ + struct vring_virtqueue_packed vring = {}; + struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = _vq->vdev; + int err; + + if (vring_alloc_queue_packed(&vring, vdev, num)) + goto err_ring; + + err = vring_alloc_state_extra_packed(&vring); + if (err) + goto err_state_extra; + + vring_free(&vq->vq); + + virtqueue_init(vq, vring.vring.num); + virtqueue_vring_attach_packed(vq, &vring); + virtqueue_vring_init_packed(vq); + + return 0; + +err_state_extra: + vring_free_packed(&vring, vdev); +err_ring: + virtqueue_reinit_packed(vq); + return -ENOMEM; +} + /* * Generic functions and exported symbols.