From patchwork Mon Aug 1 06:38:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xuan Zhuo X-Patchwork-Id: 12933491 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 E94DFC282E7 for ; Mon, 1 Aug 2022 06:41:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238825AbiHAGlE (ORCPT ); Mon, 1 Aug 2022 02:41:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34024 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237548AbiHAGkm (ORCPT ); Mon, 1 Aug 2022 02:40:42 -0400 Received: from out199-5.us.a.mail.aliyun.com (out199-5.us.a.mail.aliyun.com [47.90.199.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3A43915A03; Sun, 31 Jul 2022 23:39:55 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R201e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046059;MF=xuanzhuo@linux.alibaba.com;NM=1;PH=DS;RN=37;SR=0;TI=SMTPD_---0VL1cCmR_1659335987; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VL1cCmR_1659335987) by smtp.aliyun-inc.com; Mon, 01 Aug 2022 14:39:48 +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 v14 23/42] virtio_ring: packed: introduce virtqueue_resize_packed() Date: Mon, 1 Aug 2022 14:38:43 +0800 Message-Id: <20220801063902.129329-24-xuanzhuo@linux.alibaba.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20220801063902.129329-1-xuanzhuo@linux.alibaba.com> References: <20220801063902.129329-1-xuanzhuo@linux.alibaba.com> MIME-Version: 1.0 X-Git-Hash: 0f12e405b061 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 db06fb0ddfd6..bea5a3448217 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2036,6 +2036,36 @@ 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.