From patchwork Tue Jul 26 07:22:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xuan Zhuo X-Patchwork-Id: 12928832 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 B09E3CCA48C for ; Tue, 26 Jul 2022 07:24:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238355AbiGZHYQ (ORCPT ); Tue, 26 Jul 2022 03:24:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238218AbiGZHXZ (ORCPT ); Tue, 26 Jul 2022 03:23:25 -0400 Received: from out199-8.us.a.mail.aliyun.com (out199-8.us.a.mail.aliyun.com [47.90.199.8]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3EDE02AC73; Tue, 26 Jul 2022 00:23:17 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R611e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046051;MF=xuanzhuo@linux.alibaba.com;NM=1;PH=DS;RN=37;SR=0;TI=SMTPD_---0VKUN6a4_1658820190; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VKUN6a4_1658820190) by smtp.aliyun-inc.com; Tue, 26 Jul 2022 15:23:11 +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 v13 23/42] virtio_ring: packed: introduce virtqueue_resize_packed() Date: Tue, 26 Jul 2022 15:22:06 +0800 Message-Id: <20220726072225.19884-24-xuanzhuo@linux.alibaba.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20220726072225.19884-1-xuanzhuo@linux.alibaba.com> References: <20220726072225.19884-1-xuanzhuo@linux.alibaba.com> MIME-Version: 1.0 X-Git-Hash: 19d2a6aae0b1 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 | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 7d4c444b5a9d..98bac8c389e8 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2040,6 +2040,36 @@ static struct virtqueue *vring_create_virtqueue_packed( return NULL; } +static int virtqueue_resize_packed(struct virtqueue *_vq, u32 num) +{ + struct vring_virtqueue_packed vring_packed = {}; + struct vring_virtqueue *vq = to_vvq(_vq); + struct virtio_device *vdev = _vq->vdev; + int err; + + if (vring_alloc_queue_packed(&vring_packed, vdev, num)) + goto err_ring; + + err = vring_alloc_state_extra_packed(&vring_packed); + if (err) + goto err_state_extra; + + vring_free(&vq->vq); + + virtqueue_vring_init_packed(&vring_packed, !!vq->vq.callback); + + virtqueue_init(vq, vring_packed.vring.num); + virtqueue_vring_attach_packed(vq, &vring_packed); + + return 0; + +err_state_extra: + vring_free_packed(&vring_packed, vdev); +err_ring: + virtqueue_reinit_packed(vq); + return -ENOMEM; +} + /* * Generic functions and exported symbols.