From patchwork Wed Jun 29 06:56:46 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xuan Zhuo X-Patchwork-Id: 12899543 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 A6BFEC43334 for ; Wed, 29 Jun 2022 06:59:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232459AbiF2G7p (ORCPT ); Wed, 29 Jun 2022 02:59:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40458 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232782AbiF2G7L (ORCPT ); Wed, 29 Jun 2022 02:59:11 -0400 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C9F30B58; Tue, 28 Jun 2022 23:58:07 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R141e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045168;MF=xuanzhuo@linux.alibaba.com;NM=1;PH=DS;RN=37;SR=0;TI=SMTPD_---0VHmY1T5_1656485881; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VHmY1T5_1656485881) by smtp.aliyun-inc.com; Wed, 29 Jun 2022 14:58:02 +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 30/40] virtio_pci: support VIRTIO_F_RING_RESET Date: Wed, 29 Jun 2022 14:56:46 +0800 Message-Id: <20220629065656.54420-31-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: linux-remoteproc@vger.kernel.org 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 ++++++++++++++++++++++++++++++ drivers/virtio/virtio_ring.c | 2 + include/linux/virtio.h | 1 + 4 files changed, 108 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..754e5e10386b 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 + 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, + .reset_vq = vp_modern_reset_vq, + .enable_reset_vq = vp_modern_enable_reset_vq, }; 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, + .reset_vq = vp_modern_reset_vq, + .enable_reset_vq = vp_modern_enable_reset_vq, }; /* the PCI probing function */ diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 7b02be7fce67..82b058e8ce34 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2008,6 +2008,7 @@ static struct virtqueue *vring_create_virtqueue_packed( vq->vq.vdev = vdev; vq->vq.name = name; vq->vq.index = index; + vq->vq.reset = false; vq->we_own_ring = true; vq->notify = notify; vq->weak_barriers = weak_barriers; @@ -2487,6 +2488,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, vq->vq.vdev = vdev; vq->vq.name = name; vq->vq.index = index; + vq->vq.reset = false; vq->we_own_ring = false; vq->notify = notify; vq->weak_barriers = weak_barriers; diff --git a/include/linux/virtio.h b/include/linux/virtio.h index dc474a0d48d1..88f21796b1c3 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -33,6 +33,7 @@ struct virtqueue { unsigned int num_free; unsigned int num_max; void *priv; + bool reset; }; int virtqueue_add_outbuf(struct virtqueue *vq,