From mboxrd@z Thu Jan 1 00:00:00 1970 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 7152BC433F5 for ; Wed, 9 Mar 2022 07:51:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229838AbiCIHwh (ORCPT ); Wed, 9 Mar 2022 02:52:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39672 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229794AbiCIHwg (ORCPT ); Wed, 9 Mar 2022 02:52:36 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id C1111157237 for ; Tue, 8 Mar 2022 23:51:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646812296; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8EooiEDUIiNqsLqksX/5gFpvlfrwnXfbsnSG7xyKFRM=; b=hNK1RfRLODPTnqeWOLM64QckM1ELf/KRJ9fgqTVeieFX7lDs2p0G900CTjPEI9s02hhmbt Lg0U7IFqu/51HZ9a7nT43c/KmlCeup8oefYX+1kDLWAsvdqmtW4nH+chOJkAooXHeiC5Kz 3n+cRBpoJT2aS2y/usoFGkY1uQLGulg= Received: from mail-pj1-f69.google.com (mail-pj1-f69.google.com [209.85.216.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-102-3aZxpF7bM62o872dtQO8Vg-1; Wed, 09 Mar 2022 02:51:35 -0500 X-MC-Unique: 3aZxpF7bM62o872dtQO8Vg-1 Received: by mail-pj1-f69.google.com with SMTP id mt1-20020a17090b230100b001beef010919so3302883pjb.7 for ; Tue, 08 Mar 2022 23:51:35 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=8EooiEDUIiNqsLqksX/5gFpvlfrwnXfbsnSG7xyKFRM=; b=NZU21mgjz2SkKvgrhLKh4YhzHhms1Er1wagOSiN0KGCld5KkBK7vby2n5zdZ/8ewIq VOU9tGjR4VvMNncxiGYWVvDuVEP24HBWKL03KHdM6wDHLUsVyXKeis9ueuU7XpWOXKrq RCq279Md8B5y9/ksdsBlzCUrwTmID9Qp7NsNhgo0AwTGEXz5qVkvcAkyjZQTqht4TZe2 2rc+k6KSX/Whl1hIB6nf03a60T7X8ZvuG9tcpKB5iYkMjd1mbVcwHoOLiSrGk9wFnl9I U52tYA8zJ4y6Hb2cSW+rxDGMjwAY5R924phptLoW+28YpNr/lPH2ZAnPjeFtQlysYxJu Psfg== X-Gm-Message-State: AOAM533n4VoTiYP11yapvNfm2X2x8Cp0AzcGa6Y+IhoVNdqtyDBb0nyE eiYEbX0lbDaPd6suhkvdFIvHqegBF7BAk89dX9EjKYTvWWdNFhRYG7F9DVrIeo0K2ik4eEwKsyA uUGsXk/wfVTv7EdFHRNU90ExBRlN/6g== X-Received: by 2002:a05:6a00:1aca:b0:4e1:a2b6:5b9 with SMTP id f10-20020a056a001aca00b004e1a2b605b9mr22032640pfv.4.1646812294715; Tue, 08 Mar 2022 23:51:34 -0800 (PST) X-Google-Smtp-Source: ABdhPJw7Di4SBo0vIcLZV8aD0YrzixtPGak4ozbl1xizUy139HXfoBpN9nPz+x4ygNPWdbKEaJoHaw== X-Received: by 2002:a05:6a00:1aca:b0:4e1:a2b6:5b9 with SMTP id f10-20020a056a001aca00b004e1a2b605b9mr22032623pfv.4.1646812294417; Tue, 08 Mar 2022 23:51:34 -0800 (PST) Received: from [10.72.12.183] ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id s16-20020a63ff50000000b003650ee901e1sm1468074pgk.68.2022.03.08.23.51.18 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 08 Mar 2022 23:51:33 -0800 (PST) Message-ID: Date: Wed, 9 Mar 2022 15:51:13 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH v7 08/26] virtio_ring: extract the logic of freeing vring Content-Language: en-US To: Xuan Zhuo , virtualization@lists.linux-foundation.org, netdev@vger.kernel.org Cc: Jeff Dike , Richard Weinberger , Anton Ivanov , "Michael S. Tsirkin" , "David S. Miller" , Jakub Kicinski , Hans de Goede , Mark Gross , Vadim Pasternak , Bjorn Andersson , Mathieu Poirier , Cornelia Huck , Halil Pasic , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Alexander Gordeev , Sven Schnelle , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Johannes Berg , Vincent Whitchurch , linux-um@lists.infradead.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 References: <20220308123518.33800-1-xuanzhuo@linux.alibaba.com> <20220308123518.33800-9-xuanzhuo@linux.alibaba.com> From: Jason Wang In-Reply-To: <20220308123518.33800-9-xuanzhuo@linux.alibaba.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-remoteproc@vger.kernel.org 在 2022/3/8 下午8:35, Xuan Zhuo 写道: > Introduce vring_free() to free the vring of vq. > > Prevent double free by setting vq->reset. > > Signed-off-by: Xuan Zhuo > --- > drivers/virtio/virtio_ring.c | 25 ++++++++++++++++++++----- > include/linux/virtio.h | 8 ++++++++ > 2 files changed, 28 insertions(+), 5 deletions(-) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index b5a9bf4f45b3..e0422c04c903 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -2442,14 +2442,10 @@ struct virtqueue *vring_new_virtqueue(unsigned int index, > } > EXPORT_SYMBOL_GPL(vring_new_virtqueue); > > -void vring_del_virtqueue(struct virtqueue *_vq) > +static void __vring_free(struct virtqueue *_vq) > { > struct vring_virtqueue *vq = to_vvq(_vq); > > - spin_lock(&vq->vq.vdev->vqs_list_lock); > - list_del(&_vq->list); > - spin_unlock(&vq->vq.vdev->vqs_list_lock); > - > if (vq->we_own_ring) { > if (vq->packed_ring) { > vring_free_queue(vq->vq.vdev, > @@ -2480,6 +2476,25 @@ void vring_del_virtqueue(struct virtqueue *_vq) > kfree(vq->split.desc_state); > kfree(vq->split.desc_extra); > } > +} > + > +static void vring_free(struct virtqueue *vq) > +{ > + __vring_free(vq); > + vq->reset = VIRTIO_VQ_RESET_STEP_VRING_RELEASE; > +} > + > +void vring_del_virtqueue(struct virtqueue *_vq) > +{ > + struct vring_virtqueue *vq = to_vvq(_vq); > + > + spin_lock(&vq->vq.vdev->vqs_list_lock); > + list_del(&_vq->list); > + spin_unlock(&vq->vq.vdev->vqs_list_lock); > + > + if (_vq->reset != VIRTIO_VQ_RESET_STEP_VRING_RELEASE) > + __vring_free(_vq); > + > kfree(vq); > } > EXPORT_SYMBOL_GPL(vring_del_virtqueue); > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > index d59adc4be068..e3714e6db330 100644 > --- a/include/linux/virtio.h > +++ b/include/linux/virtio.h > @@ -10,6 +10,13 @@ > #include > #include > > +enum virtio_vq_reset_step { > + VIRTIO_VQ_RESET_STEP_NONE, > + VIRTIO_VQ_RESET_STEP_DEVICE, > + VIRTIO_VQ_RESET_STEP_VRING_RELEASE, > + VIRTIO_VQ_RESET_STEP_VRING_ATTACH, > +}; This part looks not related to the subject. And it needs detail documentation on this. But I wonder how useful it is, anyway we can check the reset status via transport specific way and in the future we may want to do more than just resizing (e.g PASID). Thanks > + > /** > * virtqueue - a queue to register buffers for sending or receiving. > * @list: the chain of virtqueues for this device > @@ -33,6 +40,7 @@ struct virtqueue { > unsigned int num_free; > unsigned int num_max; > void *priv; > + enum virtio_vq_reset_step reset; > }; > > int virtqueue_add_outbuf(struct virtqueue *vq,