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 9A7B9CCA485 for ; Thu, 21 Jul 2022 09:15:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232865AbiGUJP3 (ORCPT ); Thu, 21 Jul 2022 05:15:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47350 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232644AbiGUJP2 (ORCPT ); Thu, 21 Jul 2022 05:15:28 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 450521EC47 for ; Thu, 21 Jul 2022 02:15:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1658394925; 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=PKluuKiO4nPSBSIDesJ3n2h9tlkDSbj9xB+0JNp3iV8=; b=KGFmuzMp2N+6Hm2oks30I2y2wkGaIq1UNpqGHBIoeBeCqYfaSrWKBKic9ScLya2E8bo5fY jGDULZ+Adj7Vrkbo0RH1M5QemP8+YUj4iW7Vwqvwz0gXDSoAKXdSqq7fWE1KUoh10cMJgS UlYywgOhWI5kHvl4Ns5+2selUdhXZDQ= Received: from mail-pl1-f198.google.com (mail-pl1-f198.google.com [209.85.214.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-663-3kRisn2BM5uf18hkIqVocg-1; Thu, 21 Jul 2022 05:15:24 -0400 X-MC-Unique: 3kRisn2BM5uf18hkIqVocg-1 Received: by mail-pl1-f198.google.com with SMTP id s6-20020a170902a50600b0016d2e77252eso859415plq.18 for ; Thu, 21 Jul 2022 02:15:24 -0700 (PDT) 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=PKluuKiO4nPSBSIDesJ3n2h9tlkDSbj9xB+0JNp3iV8=; b=JtS8fdA+TdmPYwbsFptC5O6OYpOWJAHOcMvC5Z+w65gdbhSJGOYpAL4/bCNZbwOnPb P+ED3xoPjjrTLRViNis0aJzaRxh/cEju/VHo9s8EBnpcBKsFRBpKZjOyvJPasMFank4I H8VlEQqsBHojyyQcIxtOElz7Mq80fgFliR/DJ7DrBBKSoq+R5/0mmXw3t5wLxoAlYama e2yWb6WuLYS3+TeswYZcV/dCU0EXiKWGiuxr5oWAKOycRtN3iOeRK4+r1t6GsZ6DqjQJ C+HASMsyX9pGwsSfC6rv7zdjUjE+gHB566V9mFoMU+Q8hCSIEisGQNH0Bz783KEM6Edx pwRw== X-Gm-Message-State: AJIora+LG8dfJk4E0pIovD63lWVg/TWqik//zEnSVhPLxu0byv7Cw/Vi PdlOQeQXpr+ceSzUatdVGwO35q2fbxGe28Roy2eE0hcjmn8Dd74YZBMngkYnDI0a/2mGfm7sBGf ywD/kZy6YGWe7o5Dg8kd55Q== X-Received: by 2002:a65:42cc:0:b0:3a9:f71f:33f9 with SMTP id l12-20020a6542cc000000b003a9f71f33f9mr36793852pgp.391.1658394923335; Thu, 21 Jul 2022 02:15:23 -0700 (PDT) X-Google-Smtp-Source: AGRyM1sgEw6i8bsR36Y8ICw8UMYj7/O02SOjej4lcmI0dJ1BovICarsVAAvAc6/oM7JcSOz5o3pTJA== X-Received: by 2002:a65:42cc:0:b0:3a9:f71f:33f9 with SMTP id l12-20020a6542cc000000b003a9f71f33f9mr36793799pgp.391.1658394922973; Thu, 21 Jul 2022 02:15:22 -0700 (PDT) Received: from [10.72.12.47] ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id y20-20020a170902e19400b0016c35b21901sm1077023pla.195.2022.07.21.02.15.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 21 Jul 2022 02:15:22 -0700 (PDT) Message-ID: Date: Thu, 21 Jul 2022 17:15:11 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH v12 30/40] virtio_pci: support VIRTIO_F_RING_RESET Content-Language: en-US To: Xuan Zhuo , virtualization@lists.linux-foundation.org Cc: Richard Weinberger , Anton Ivanov , Johannes Berg , "Michael S. Tsirkin" , "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 , 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 References: <20220720030436.79520-1-xuanzhuo@linux.alibaba.com> <20220720030436.79520-31-xuanzhuo@linux.alibaba.com> From: Jason Wang In-Reply-To: <20220720030436.79520-31-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-s390@vger.kernel.org 在 2022/7/20 11:04, Xuan Zhuo 写道: > This patch implements virtio pci support for QUEUE RESET. > > Performing reset on a queue is divided into these steps: > > 1. notify the device to reset the queue > 2. recycle the buffer submitted > 3. reset the vring (may re-alloc) > 4. mmap vring to device, and enable the queue > > This patch implements virtio_reset_vq(), virtio_enable_resetq() in the > pci scenario. > > Signed-off-by: Xuan Zhuo > --- > drivers/virtio/virtio_pci_common.c | 12 +++- > drivers/virtio/virtio_pci_modern.c | 96 ++++++++++++++++++++++++++++++ > 2 files changed, 105 insertions(+), 3 deletions(-) > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > index ca51fcc9daab..ad258a9d3b9f 100644 > --- a/drivers/virtio/virtio_pci_common.c > +++ b/drivers/virtio/virtio_pci_common.c > @@ -214,9 +214,15 @@ static void vp_del_vq(struct virtqueue *vq) > struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index]; > unsigned long flags; > > - spin_lock_irqsave(&vp_dev->lock, flags); > - list_del(&info->node); > - spin_unlock_irqrestore(&vp_dev->lock, flags); > + /* > + * If it fails during re-enable reset vq. This way we won't rejoin > + * info->node to the queue. Prevent unexpected irqs. > + */ > + if (!vq->reset) { > + spin_lock_irqsave(&vp_dev->lock, flags); > + list_del(&info->node); > + spin_unlock_irqrestore(&vp_dev->lock, flags); > + } > > vp_dev->del_vq(info); > kfree(info); > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > index 9041d9a41b7d..4d28b6918c80 100644 > --- a/drivers/virtio/virtio_pci_modern.c > +++ b/drivers/virtio/virtio_pci_modern.c > @@ -34,6 +34,9 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features) > if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) && > pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV)) > __virtio_set_bit(vdev, VIRTIO_F_SR_IOV); > + > + if (features & BIT_ULL(VIRTIO_F_RING_RESET)) > + __virtio_set_bit(vdev, VIRTIO_F_RING_RESET); > } > > /* virtio config->finalize_features() implementation */ > @@ -199,6 +202,95 @@ static int vp_active_vq(struct virtqueue *vq, u16 msix_vec) > return 0; > } > > +static int vp_modern_reset_vq(struct virtqueue *vq) > +{ > + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > + struct virtio_pci_vq_info *info; > + unsigned long flags; > + > + if (!virtio_has_feature(vq->vdev, VIRTIO_F_RING_RESET)) > + return -ENOENT; > + > + vp_modern_set_queue_reset(mdev, vq->index); > + > + info = vp_dev->vqs[vq->index]; > + > + /* delete vq from irq handler */ > + spin_lock_irqsave(&vp_dev->lock, flags); > + list_del(&info->node); > + spin_unlock_irqrestore(&vp_dev->lock, flags); > + > + INIT_LIST_HEAD(&info->node); > + > + /* For the case where vq has an exclusive irq, to prevent the irq from > + * being received again and the pending irq, call synchronize_irq(), and > + * break it. > + * > + * We can't use disable_irq() since it conflicts with the affinity > + * managed IRQ that is used by some drivers. So this is done on top of > + * IRQ hardening. > + * > + * In the scenario based on shared interrupts, vq will be searched from > + * the queue virtqueues. Since the previous list_del() has been deleted > + * from the queue, it is impossible for vq to be called in this case. > + * There is no need to close the corresponding interrupt. > + */ > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) { > +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION > + __virtqueue_break(vq); > +#endif I think we should do this unconditionally since it's an independent feature, though the list_del() above should be sufficient. > + synchronize_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); > + } > + > + vq->reset = true; > + > + return 0; > +} > + > +static int vp_modern_enable_reset_vq(struct virtqueue *vq) > +{ > + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > + struct virtio_pci_vq_info *info; > + unsigned long flags, index; > + int err; > + > + if (!vq->reset) > + return -EBUSY; > + > + index = vq->index; > + info = vp_dev->vqs[index]; > + > + if (vp_modern_get_queue_reset(mdev, index)) > + return -EBUSY; > + > + if (vp_modern_get_queue_enable(mdev, index)) > + return -EBUSY; > + > + err = vp_active_vq(vq, info->msix_vector); > + if (err) > + return err; > + > + if (vq->callback) { > + spin_lock_irqsave(&vp_dev->lock, flags); > + list_add(&info->node, &vp_dev->virtqueues); > + spin_unlock_irqrestore(&vp_dev->lock, flags); > + } else { > + INIT_LIST_HEAD(&info->node); > + } > + > +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) > + __virtqueue_unbreak(vq); > +#endif > + > + vp_modern_set_queue_enable(&vp_dev->mdev, index, true); > + vq->reset = false; > + > + return 0; > +} > + > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > { > return vp_modern_config_vector(&vp_dev->mdev, vector); > @@ -413,6 +505,8 @@ static const struct virtio_config_ops virtio_pci_config_nodev_ops = { > .set_vq_affinity = vp_set_vq_affinity, > .get_vq_affinity = vp_get_vq_affinity, > .get_shm_region = vp_get_shm_region, > + .disable_vq_and_reset = vp_modern_reset_vq, > + .enable_vq_after_reset = vp_modern_enable_reset_vq, Nit: To be consistent, let's use vp_modern_disable_vq_and_reset() and vp_modern_enable_vq_after_reset() Thanks > }; > > static const struct virtio_config_ops virtio_pci_config_ops = { > @@ -431,6 +525,8 @@ static const struct virtio_config_ops virtio_pci_config_ops = { > .set_vq_affinity = vp_set_vq_affinity, > .get_vq_affinity = vp_get_vq_affinity, > .get_shm_region = vp_get_shm_region, > + .disable_vq_and_reset = vp_modern_reset_vq, > + .enable_vq_after_reset = vp_modern_enable_reset_vq, > }; > > /* the PCI probing function */