From patchwork Wed Jun 29 06:56:30 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xuan Zhuo X-Patchwork-Id: 12899402 X-Patchwork-Delegate: kuba@kernel.org 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 EEF83CCA482 for ; Wed, 29 Jun 2022 06:58:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232723AbiF2G5v (ORCPT ); Wed, 29 Jun 2022 02:57:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37156 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232607AbiF2G5g (ORCPT ); Wed, 29 Jun 2022 02:57:36 -0400 Received: from out30-131.freemail.mail.aliyun.com (out30-131.freemail.mail.aliyun.com [115.124.30.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2B71030540; Tue, 28 Jun 2022 23:57:34 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R981e4;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_---0VHmYOtE_1656485846; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VHmYOtE_1656485846) by smtp.aliyun-inc.com; Wed, 29 Jun 2022 14:57:27 +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 14/40] virtio_ring: split: introduce virtqueue_resize_split() Date: Wed, 29 Jun 2022 14:56:30 +0800 Message-Id: <20220629065656.54420-15-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: netdev@vger.kernel.org virtio ring split 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(virtqueue_reinit_split()) the virtqueue to ensure that the vring can be used. In addition, vring_align, may_reduce_num are necessary for reallocating vring, so they are retained for creating vq. Signed-off-by: Xuan Zhuo Acked-by: Jason Wang --- drivers/virtio/virtio_ring.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 9c83c5e6d5a9..1aaa1e5f9991 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -212,6 +212,7 @@ struct vring_virtqueue { }; static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num); +static void vring_free(struct virtqueue *_vq); /* * Helpers. @@ -1114,6 +1115,37 @@ static struct virtqueue *vring_create_virtqueue_split( return vq; } +static int virtqueue_resize_split(struct virtqueue *_vq, u32 num) +{ + struct vring_virtqueue *vq = to_vvq(_vq); + struct vring_virtqueue_split vring = {}; + struct virtio_device *vdev = _vq->vdev; + int err; + + err = vring_alloc_queue_split(&vring, vdev, num, vq->split.vring_align, + vq->split.may_reduce_num); + if (err) + goto err; + + err = vring_alloc_state_extra_split(&vring); + if (err) { + vring_free_split(&vring, vdev); + goto err; + } + + vring_free(&vq->vq); + + virtqueue_init(vq, vring.vring.num); + virtqueue_vring_attach_split(vq, &vring); + virtqueue_vring_init_split(vq); + + return 0; + +err: + virtqueue_reinit_split(vq); + return -ENOMEM; +} + /* * Packed ring specific functions - *_packed().