From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 5C40FA2E1B for ; Wed, 4 Sep 2019 08:56:42 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 5CF341E8BF; Wed, 4 Sep 2019 08:56:41 +0200 (CEST) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by dpdk.org (Postfix) with ESMTP id C5F0E1E8B1; Wed, 4 Sep 2019 08:56:39 +0200 (CEST) Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1BAF4307D88C; Wed, 4 Sep 2019 06:56:39 +0000 (UTC) Received: from [10.36.112.25] (ovpn-112-25.ams2.redhat.com [10.36.112.25]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B4B5A19C4F; Wed, 4 Sep 2019 06:56:34 +0000 (UTC) To: Jason Wang , Tiwei Bie Cc: zhihong.wang@intel.com, amorenoz@redhat.com, xiao.w.wang@intel.com, dev@dpdk.org, jfreimann@redhat.com, stable@dpdk.org References: <20190829080000.20806-1-maxime.coquelin@redhat.com> <20190829080000.20806-11-maxime.coquelin@redhat.com> <20190903053006.GA32701@___> <20190903084909.GA9622@___> <718b4bc8-1a04-689f-5a3a-b6d80c517720@redhat.com> From: Maxime Coquelin Openpgp: preference=signencrypt Autocrypt: addr=maxime.coquelin@redhat.com; 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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <718b4bc8-1a04-689f-5a3a-b6d80c517720@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Wed, 04 Sep 2019 06:56:39 +0000 (UTC) Subject: Re: [dpdk-dev] [PATCH 10/15] net/virtio: add vDPA op to configure and start the device X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 9/4/19 6:06 AM, Jason Wang wrote: > > On 2019/9/3 下午4:49, Tiwei Bie wrote: >> On Tue, Sep 03, 2019 at 09:40:25AM +0200, Maxime Coquelin wrote: >>> On 9/3/19 7:30 AM, Tiwei Bie wrote: >>>> On Thu, Aug 29, 2019 at 09:59:55AM +0200, Maxime Coquelin wrote: >>>>> In order to support multi-queue, we need to implement the control >>>>> path. The problem is that both the Vhost-user master and slave use >>>>> VAs in their processes address spaces as IOVAs, which creates >>>>> collusions between the data rings IOVAs managed the master, and >>>>> the Control ring IOVAs. The trick here is to remmap the Control >>>>> ring memory to another range, after the slave is aware of master's >>>>> ranges. >>>>> >>>>> Signed-off-by: Maxime Coquelin >>>>> --- >>>>>   drivers/net/virtio/virtio_vdpa.c | 255 >>>>> +++++++++++++++++++++++++++++++ >>>>>   1 file changed, 255 insertions(+) >>>>> >>>>> diff --git a/drivers/net/virtio/virtio_vdpa.c >>>>> b/drivers/net/virtio/virtio_vdpa.c >>>>> index fc52a8e92..13b4dd07d 100644 >>>>> --- a/drivers/net/virtio/virtio_vdpa.c >>>>> +++ b/drivers/net/virtio/virtio_vdpa.c >>>>> @@ -106,6 +106,127 @@ find_internal_resource_by_dev(struct >>>>> rte_pci_device *pdev) >>>>>       return list; >>>>>   } >>>>>   +static int >>>>> +virtio_vdpa_dma_map_ctrl_queue(struct virtio_vdpa_device *dev, int >>>>> do_map, >>>>> +        uint64_t iova) >>>>> +{ >>>>> +    const struct rte_memzone *mz; >>>>> +    int ret; >>>>> + >>>>> +    /* >>>>> +     * IOVAs are processes VAs. We cannot use them as the Data and >>>>> Control >>>>> +     * paths are run in different processes, which may (does) lead to >>>>> +     * collusions. The trick here is to fixup Ctrl path IOVAs so >>>>> that they >>>>> +     * start after the Data path ranges. >>>>> +     */ >>>>> +    if (do_map) { >>>>> +        mz = dev->cvq->cq.mz; >>>>> +        ret = rte_vfio_container_dma_map(dev->vfio_container_fd, >>>>> +                (uint64_t)(uintptr_t)mz->addr, >>>>> +                iova, mz->len); >>>>> +        if (ret < 0) { >>>>> +            DRV_LOG(ERR, "Failed to map ctrl ring (%d)", ret); >>>>> +            return ret; >>>>> +        } >>>>> + >>>>> +        dev->cvq->vq_ring_mem = iova; >>>>> +        iova += mz->len; >>>>> + >>>>> +        mz = dev->cvq->cq.virtio_net_hdr_mz; >>>>> +        ret = rte_vfio_container_dma_map(dev->vfio_container_fd, >>>>> +                (uint64_t)(uintptr_t)mz->addr, >>>>> +                iova, mz->len); >>>>> +        if (ret < 0) { >>>>> +            DRV_LOG(ERR, "Failed to map ctrl headers (%d)", ret); >>>>> +            return ret; >>>>> +        } >>>> This will allow guest to access the cq.mz and cq.virtio_net_hdr_mz >>>> via the device which may have potential risks. >>> I get what you mean, but I'm not sure to see how we could avoid that. >>> AFAIU, we need to map the control queue in the device IOMMU, otherwise >>> how could the host (in case of virtual device) or the NIC (in case of >>> Virtio offload), could access the ring? >>> Any thoughts? >> I also don't see a way to avoid that. That's why I said in below >> thread that I think the control queue based interface seems not a >> quite good interface for a backend device: >> >> https://lkml.org/lkml/2019/9/2/934 >> >> In IFCVF NIC, we added a MMIO based interface to replace control >> queue for the multiqueue setup in vDPA mode. >> >> Jason is proposing some changes to make virtio device suitable >> for backend device. I'm not sure whether it's possible to cover >> this case as well.. > > > A silly question, can we do dynamic mapping like what kernel driver did > here? Not silly at all, it is of course possible. I will implement that in my v2. Thanks! Maxime > Thanks > > >> >> Regards, >> Tiwei >> >>> Thanks, >>> Maxime >>>> Regards, >>>> Tiwei >>>> >>>>> + >>>>> +        dev->cvq->cq.virtio_net_hdr_mem = iova; >>>>> +    } else { >>>>> +        mz = dev->cvq->cq.mz; >>>>> +        ret = rte_vfio_container_dma_unmap(dev->vfio_container_fd, >>>>> +                (uint64_t)(uintptr_t)mz->addr, >>>>> +                iova, mz->len); >>>>> +        if (ret < 0) { >>>>> +            DRV_LOG(ERR, "Failed to unmap ctrl ring (%d)", ret); >>>>> +            return ret; >>>>> +        } >>>>> + >>>>> +        dev->cvq->vq_ring_mem = 0; >>>>> +        iova += mz->len; >>>>> + >>>>> +        mz = dev->cvq->cq.virtio_net_hdr_mz; >>>>> +        ret = rte_vfio_container_dma_unmap(dev->vfio_container_fd, >>>>> +                (uint64_t)(uintptr_t)mz->addr, >>>>> +                iova, mz->len); >>>>> +        if (ret < 0) { >>>>> +            DRV_LOG(ERR, "Failed to unmap ctrl headers (%d)", ret); >>>>> +            return ret; >>>>> +        } >>>>> + >>>>> +        dev->cvq->cq.virtio_net_hdr_mem = 0; >>>>> +    } >>>>> + >>>>> +    return 0; >>>>> +} >>>>> + >>>>> +static int >>>>> +virtio_vdpa_dma_map(struct virtio_vdpa_device *dev, int do_map) >>>>> +{ >>>>> +    uint32_t i; >>>>> +    int ret; >>>>> +    struct rte_vhost_memory *mem = NULL; >>>>> +    int vfio_container_fd; >>>>> +    uint64_t avail_iova = 0; >>>>> + >>>>> +    ret = rte_vhost_get_mem_table(dev->vid, &mem); >>>>> +    if (ret < 0 || !mem) { >>>>> +        DRV_LOG(ERR, "failed to get VM memory layout."); >>>>> +        return ret; >>>>> +    } >>>>> + >>>>> +    vfio_container_fd = dev->vfio_container_fd; >>>>> + >>>>> +    for (i = 0; i < mem->nregions; i++) { >>>>> +        struct rte_vhost_mem_region *reg; >>>>> + >>>>> +        reg = &mem->regions[i]; >>>>> +        DRV_LOG(INFO, "%s, region %u: HVA 0x%" PRIx64 ", " >>>>> +            "GPA 0x%" PRIx64 ", size 0x%" PRIx64 ".", >>>>> +            do_map ? "DMA map" : "DMA unmap", i, >>>>> +            reg->host_user_addr, reg->guest_phys_addr, reg->size); >>>>> + >>>>> +        if (reg->guest_phys_addr + reg->size > avail_iova) >>>>> +            avail_iova = reg->guest_phys_addr + reg->size; >>>>> + >>>>> +        if (do_map) { >>>>> +            ret = rte_vfio_container_dma_map(vfio_container_fd, >>>>> +                reg->host_user_addr, reg->guest_phys_addr, >>>>> +                reg->size); >>>>> +            if (ret < 0) { >>>>> +                DRV_LOG(ERR, "DMA map failed."); >>>>> +                goto exit; >>>>> +            } >>>>> +        } else { >>>>> +            ret = rte_vfio_container_dma_unmap(vfio_container_fd, >>>>> +                reg->host_user_addr, reg->guest_phys_addr, >>>>> +                reg->size); >>>>> +            if (ret < 0) { >>>>> +                DRV_LOG(ERR, "DMA unmap failed."); >>>>> +                goto exit; >>>>> +            } >>>>> +        } >>>>> +    } >>>>> + >>>>> +    if (dev->cvq) >>>>> +        ret = virtio_vdpa_dma_map_ctrl_queue(dev, do_map, >>>>> avail_iova); >>>>> + >>>>> +exit: >>>>> +    free(mem); >>>>> + >>>>> +    return ret; >>>>> +} >>>>> + >>>>>   static int >>>>>   virtio_vdpa_vfio_setup(struct virtio_vdpa_device *dev) >>>>>   { >>>>> @@ -216,10 +337,144 @@ virtio_vdpa_get_protocol_features(int did >>>>> __rte_unused, uint64_t *features) >>>>>       return 0; >>>>>   } >>>>>   +static uint64_t >>>>> +hva_to_gpa(int vid, uint64_t hva) >>>>> +{ >>>>> +    struct rte_vhost_memory *mem = NULL; >>>>> +    struct rte_vhost_mem_region *reg; >>>>> +    uint32_t i; >>>>> +    uint64_t gpa = 0; >>>>> + >>>>> +    if (rte_vhost_get_mem_table(vid, &mem) < 0) >>>>> +        goto exit; >>>>> + >>>>> +    for (i = 0; i < mem->nregions; i++) { >>>>> +        reg = &mem->regions[i]; >>>>> + >>>>> +        if (hva >= reg->host_user_addr && >>>>> +                hva < reg->host_user_addr + reg->size) { >>>>> +            gpa = hva - reg->host_user_addr + reg->guest_phys_addr; >>>>> +            break; >>>>> +        } >>>>> +    } >>>>> + >>>>> +exit: >>>>> +    if (mem) >>>>> +        free(mem); >>>>> +    return gpa; >>>>> +} >>>>> + >>>>> +static int >>>>> +virtio_vdpa_start(struct virtio_vdpa_device *dev) >>>>> +{ >>>>> +    struct virtio_hw *hw = &dev->hw; >>>>> +    int i, vid, nr_vring, ret; >>>>> +    struct rte_vhost_vring vr; >>>>> +    struct virtio_pmd_ctrl ctrl; >>>>> +    int dlen[1]; >>>>> + >>>>> +    vid = dev->vid; >>>>> +    nr_vring = rte_vhost_get_vring_num(vid); >>>>> + >>>>> +    if (dev->vqs) >>>>> +        rte_free(dev->vqs); >>>>> + >>>>> +    dev->vqs = rte_zmalloc("virtio_vdpa", sizeof(*dev->vqs) * >>>>> nr_vring, 0); >>>>> + >>>>> +    for (i = 0; i < nr_vring; i++) { >>>>> +        struct virtqueue *vq = &dev->vqs[i]; >>>>> + >>>>> +        rte_vhost_get_vhost_vring(vid, i, &vr); >>>>> + >>>>> +        vq->vq_queue_index = i; >>>>> +        vq->vq_nentries = vr.size; >>>>> +        vq->vq_ring_mem = hva_to_gpa(vid, >>>>> (uint64_t)(uintptr_t)vr.desc); >>>>> +        if (vq->vq_ring_mem  == 0) { >>>>> +            DRV_LOG(ERR, "Fail to get GPA for descriptor ring."); >>>>> +            ret = -1; >>>>> +            goto out_free_vqs; >>>>> +        } >>>>> + >>>>> +        ret = VTPCI_OPS(hw)->setup_queue(hw, vq); >>>>> +        if (ret) { >>>>> +            DRV_LOG(ERR, "Fail to setup queue."); >>>>> +            goto out_free_vqs; >>>>> +        } >>>>> +    } >>>>> + >>>>> +    if (dev->cvq) { >>>>> +        ret = VTPCI_OPS(hw)->setup_queue(hw, dev->cvq); >>>>> +        if (ret) { >>>>> +            DRV_LOG(ERR, "Fail to setup ctrl queue."); >>>>> +            goto out_free_vqs; >>>>> +        } >>>>> +    } >>>>> + >>>>> +    vtpci_set_status(hw, VIRTIO_CONFIG_STATUS_DRIVER_OK); >>>>> + >>>>> +    if (!dev->cvq) >>>>> +        return 0; >>>>> + >>>>> +    ctrl.hdr.class = VIRTIO_NET_CTRL_MQ; >>>>> +    ctrl.hdr.cmd = VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET; >>>>> +    memcpy(ctrl.data, &dev->max_queue_pairs, sizeof(uint16_t)); >>>>> + >>>>> +    dlen[0] = sizeof(uint16_t); >>>>> + >>>>> +    ret = virtio_send_command(hw->cvq, &ctrl, dlen, 1); >>>>> +    if (ret) { >>>>> +        DRV_LOG(ERR, "Multiqueue configured but send command " >>>>> +              "failed, this is too late now..."); >>>>> +        ret = -EINVAL; >>>>> +        goto out_free_vqs; >>>>> +    } >>>>> + >>>>> +    return 0; >>>>> +out_free_vqs: >>>>> +    rte_free(dev->vqs); >>>>> + >>>>> +    return ret; >>>>> +} >>>>> + >>>>> +static int >>>>> +virtio_vdpa_dev_config(int vid) >>>>> +{ >>>>> +    int did, ret; >>>>> +    struct internal_list *list; >>>>> +    struct virtio_vdpa_device *dev; >>>>> + >>>>> +    did = rte_vhost_get_vdpa_device_id(vid); >>>>> +    list = find_internal_resource_by_did(did); >>>>> +    if (list == NULL) { >>>>> +        DRV_LOG(ERR, "Invalid device id: %d", did); >>>>> +        return -1; >>>>> +    } >>>>> + >>>>> +    dev = list->dev; >>>>> +    dev->vid = vid; >>>>> + >>>>> +    rte_spinlock_lock(&dev->lock); >>>>> + >>>>> +    ret = virtio_vdpa_dma_map(dev, 1); >>>>> +    if (ret) >>>>> +        goto out_unlock; >>>>> + >>>>> +    ret = virtio_vdpa_start(dev); >>>>> + >>>>> +    if (rte_vhost_host_notifier_ctrl(vid, true) != 0) >>>>> +        DRV_LOG(NOTICE, "vDPA (%d): software relay is used.", did); >>>>> + >>>>> +out_unlock: >>>>> +    rte_spinlock_unlock(&dev->lock); >>>>> + >>>>> +    return ret; >>>>> +} >>>>> + >>>>>   static struct rte_vdpa_dev_ops virtio_vdpa_ops = { >>>>>       .get_queue_num = virtio_vdpa_get_queue_num, >>>>>       .get_features = virtio_vdpa_get_features, >>>>>       .get_protocol_features = virtio_vdpa_get_protocol_features, >>>>> +    .dev_conf = virtio_vdpa_dev_config, >>>>>   }; >>>>>     static inline int >>>>> --  >>>>> 2.21.0 >>>>>