From patchwork Fri Jun 24 02:55:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xuan Zhuo X-Patchwork-Id: 12893487 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 B08FCCCA486 for ; Fri, 24 Jun 2022 02:57:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231316AbiFXC5d (ORCPT ); Thu, 23 Jun 2022 22:57:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231470AbiFXC5L (ORCPT ); Thu, 23 Jun 2022 22:57:11 -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 A5F7B62BEB; Thu, 23 Jun 2022 19:57:04 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R541e4;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_---0VHEo9HX_1656039417; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VHEo9HX_1656039417) by smtp.aliyun-inc.com; Fri, 24 Jun 2022 10:56:58 +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 v10 16/41] virtio_ring: split: introduce virtqueue_resize_split() Date: Fri, 24 Jun 2022 10:55:56 +0800 Message-Id: <20220624025621.128843-17-xuanzhuo@linux.alibaba.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20220624025621.128843-1-xuanzhuo@linux.alibaba.com> References: <20220624025621.128843-1-xuanzhuo@linux.alibaba.com> MIME-Version: 1.0 X-Git-Hash: fef800c86cd2 Precedence: bulk List-ID: X-Mailing-List: linux-remoteproc@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 --- 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 8738ec690621..1ba00e73d601 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -210,6 +210,7 @@ struct vring_virtqueue { }; static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num); +static void vring_free(struct virtqueue *_vq); /* * Helpers. @@ -1109,6 +1110,37 @@ 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().