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[79.178.12.128]) by smtp.gmail.com with ESMTPSA id f23sm746781qkh.94.2019.11.07.01.02.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Nov 2019 01:02:24 -0800 (PST) Date: Thu, 7 Nov 2019 04:02:18 -0500 From: "Michael S. Tsirkin" To: Tiwei Bie Cc: jasowang@redhat.com, alex.williamson@redhat.com, maxime.coquelin@redhat.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, dan.daly@intel.com, cunming.liang@intel.com, zhihong.wang@intel.com, lingshan.zhu@intel.com Subject: Re: [PATCH v6] vhost: introduce mdev based hardware backend Message-ID: <20191107040207-mutt-send-email-mst@kernel.org> References: <20191107073530.15291-1-tiwei.bie@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191107073530.15291-1-tiwei.bie@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 07, 2019 at 03:35:30PM +0800, Tiwei Bie wrote: > This patch introduces a mdev based hardware vhost backend. > This backend is built on top of the same abstraction used > in virtio-mdev and provides a generic vhost interface for > userspace to accelerate the virtio devices in guest. > > This backend is implemented as a mdev device driver on top > of the same mdev device ops used in virtio-mdev but using > a different mdev class id, and it will register the device > as a VFIO device for userspace to use. Userspace can setup > the IOMMU with the existing VFIO container/group APIs and > then get the device fd with the device name. After getting > the device fd, userspace can use vhost ioctls on top of it > to setup the backend. > > Signed-off-by: Tiwei Bie Acked-by: Michael S. Tsirkin > --- > This patch depends on below series: > https://lkml.org/lkml/2019/11/6/538 > > v5 -> v6: > - Filter out VHOST_SET_LOG_BASE/VHOST_SET_LOG_FD (Jason); > - Simplify len/off check (Jason); > - Address checkpatch warnings, some of them are ignored > to keep the coding style consistent with existing ones; > > v4 -> v5: > - Rebase on top of virtio-mdev series v8; > - Use the virtio_ops of mdev_device in vhost-mdev (Jason); > - Some minor improvements on commit log; > > v3 -> v4: > - Rebase on top of virtio-mdev series v6; > - Some minor tweaks and improvements; > > v2 -> v3: > - Fix the return value (Jason); > - Don't cache unnecessary information in vhost-mdev (Jason); > - Get rid of the memset in open (Jason); > - Add comments for VHOST_SET_MEM_TABLE, ... (Jason); > - Filter out unsupported features in vhost-mdev (Jason); > - Add _GET_DEVICE_ID ioctl (Jason); > - Add _GET_CONFIG/_SET_CONFIG ioctls (Jason); > - Drop _GET_QUEUE_NUM ioctl (Jason); > - Fix the copy-paste errors in _IOW/_IOR usage; > - Some minor fixes and improvements; > > v1 -> v2: > - Replace _SET_STATE with _SET_STATUS (MST); > - Check status bits at each step (MST); > - Report the max ring size and max number of queues (MST); > - Add missing MODULE_DEVICE_TABLE (Jason); > - Only support the network backend w/o multiqueue for now; > - Some minor fixes and improvements; > - Rebase on top of virtio-mdev series v4; > > RFC v4 -> v1: > - Implement vhost-mdev as a mdev device driver directly and > connect it to VFIO container/group. (Jason); > - Pass ring addresses as GPAs/IOVAs in vhost-mdev to avoid > meaningless HVA->GPA translations (Jason); > > RFC v3 -> RFC v4: > - Build vhost-mdev on top of the same abstraction used by > virtio-mdev (Jason); > - Introduce vhost fd and pass VFIO fd via SET_BACKEND ioctl (MST); > > RFC v2 -> RFC v3: > - Reuse vhost's ioctls instead of inventing a VFIO regions/irqs > based vhost protocol on top of vfio-mdev (Jason); > > RFC v1 -> RFC v2: > - Introduce a new VFIO device type to build a vhost protocol > on top of vfio-mdev; > > drivers/vfio/mdev/mdev_core.c | 21 ++ > drivers/vhost/Kconfig | 12 + > drivers/vhost/Makefile | 3 + > drivers/vhost/mdev.c | 556 +++++++++++++++++++++++++++++++ > include/linux/mdev.h | 5 + > include/uapi/linux/vhost.h | 21 ++ > include/uapi/linux/vhost_types.h | 8 + > 7 files changed, 626 insertions(+) > create mode 100644 drivers/vhost/mdev.c > > diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c > index c58253404ed5..d855be5afbae 100644 > --- a/drivers/vfio/mdev/mdev_core.c > +++ b/drivers/vfio/mdev/mdev_core.c > @@ -99,6 +99,27 @@ mdev_get_virtio_ops(struct mdev_device *mdev) > } > EXPORT_SYMBOL(mdev_get_virtio_ops); > > +/* > + * Specify the vhost device ops for the mdev device, this > + * must be called during create() callback for vhost mdev device. > + */ > +void mdev_set_vhost_ops(struct mdev_device *mdev, > + const struct mdev_virtio_device_ops *vhost_ops) > +{ > + mdev_set_class(mdev, MDEV_CLASS_ID_VHOST); > + mdev->virtio_ops = vhost_ops; > +} > +EXPORT_SYMBOL(mdev_set_vhost_ops); > + > +/* Get the vhost device ops for the mdev device. */ > +const struct mdev_virtio_device_ops * > +mdev_get_vhost_ops(struct mdev_device *mdev) > +{ > + WARN_ON(mdev->class_id != MDEV_CLASS_ID_VHOST); > + return mdev->virtio_ops; > +} > +EXPORT_SYMBOL(mdev_get_vhost_ops); > + > struct device *mdev_dev(struct mdev_device *mdev) > { > return &mdev->dev; > diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig > index 3d03ccbd1adc..062cada28f89 100644 > --- a/drivers/vhost/Kconfig > +++ b/drivers/vhost/Kconfig > @@ -34,6 +34,18 @@ config VHOST_VSOCK > To compile this driver as a module, choose M here: the module will be called > vhost_vsock. > > +config VHOST_MDEV > + tristate "Vhost driver for Mediated devices" > + depends on EVENTFD && VFIO && VFIO_MDEV > + select VHOST > + default n > + ---help--- > + This kernel module can be loaded in host kernel to accelerate > + guest virtio devices with the mediated device based backends. > + > + To compile this driver as a module, choose M here: the module will > + be called vhost_mdev. > + > config VHOST > tristate > ---help--- > diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile > index 6c6df24f770c..ad9c0f8c6d8c 100644 > --- a/drivers/vhost/Makefile > +++ b/drivers/vhost/Makefile > @@ -10,4 +10,7 @@ vhost_vsock-y := vsock.o > > obj-$(CONFIG_VHOST_RING) += vringh.o > > +obj-$(CONFIG_VHOST_MDEV) += vhost_mdev.o > +vhost_mdev-y := mdev.o > + > obj-$(CONFIG_VHOST) += vhost.o > diff --git a/drivers/vhost/mdev.c b/drivers/vhost/mdev.c > new file mode 100644 > index 000000000000..96aab09969b5 > --- /dev/null > +++ b/drivers/vhost/mdev.c > @@ -0,0 +1,556 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Vhost driver for mediated device based backends. > + * > + * Copyright (C) 2018-2019 Intel Corporation. > + * > + * Author: Tiwei Bie > + * > + * Thanks to Jason Wang and Michael S. Tsirkin for the valuable > + * comments and suggestions. And thanks to Cunming Liang and > + * Zhihong Wang for all their supports. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include "vhost.h" > + > +enum { > + VHOST_MDEV_FEATURES = > + (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) | > + (1ULL << VIRTIO_F_ANY_LAYOUT) | > + (1ULL << VIRTIO_F_VERSION_1) | > + (1ULL << VIRTIO_F_IOMMU_PLATFORM) | > + (1ULL << VIRTIO_F_RING_PACKED) | > + (1ULL << VIRTIO_F_ORDER_PLATFORM) | > + (1ULL << VIRTIO_RING_F_INDIRECT_DESC) | > + (1ULL << VIRTIO_RING_F_EVENT_IDX), > + > + VHOST_MDEV_NET_FEATURES = VHOST_MDEV_FEATURES | > + (1ULL << VIRTIO_NET_F_CSUM) | > + (1ULL << VIRTIO_NET_F_GUEST_CSUM) | > + (1ULL << VIRTIO_NET_F_MTU) | > + (1ULL << VIRTIO_NET_F_MAC) | > + (1ULL << VIRTIO_NET_F_GUEST_TSO4) | > + (1ULL << VIRTIO_NET_F_GUEST_TSO6) | > + (1ULL << VIRTIO_NET_F_GUEST_ECN) | > + (1ULL << VIRTIO_NET_F_GUEST_UFO) | > + (1ULL << VIRTIO_NET_F_HOST_TSO4) | > + (1ULL << VIRTIO_NET_F_HOST_TSO6) | > + (1ULL << VIRTIO_NET_F_HOST_ECN) | > + (1ULL << VIRTIO_NET_F_HOST_UFO) | > + (1ULL << VIRTIO_NET_F_MRG_RXBUF) | > + (1ULL << VIRTIO_NET_F_STATUS) | > + (1ULL << VIRTIO_NET_F_SPEED_DUPLEX), > +}; > + > +/* Currently, only network backend w/o multiqueue is supported. */ > +#define VHOST_MDEV_VQ_MAX 2 > + > +struct vhost_mdev { > + /* The lock is to protect this structure. */ > + struct mutex mutex; > + struct vhost_dev dev; > + struct vhost_virtqueue *vqs; > + int nvqs; > + int virtio_id; > + bool opened; > + struct mdev_device *mdev; > +}; > + > +static const u64 vhost_mdev_features[] = { > + [VIRTIO_ID_NET] = VHOST_MDEV_NET_FEATURES, > +}; > + > +static void handle_vq_kick(struct vhost_work *work) > +{ > + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, > + poll.work); > + struct vhost_mdev *m = container_of(vq->dev, struct vhost_mdev, dev); > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(m->mdev); > + > + ops->kick_vq(m->mdev, vq - m->vqs); > +} > + > +static irqreturn_t vhost_mdev_virtqueue_cb(void *private) > +{ > + struct vhost_virtqueue *vq = private; > + struct eventfd_ctx *call_ctx = vq->call_ctx; > + > + if (call_ctx) > + eventfd_signal(call_ctx, 1); > + > + return IRQ_HANDLED; > +} > + > +static void vhost_mdev_reset(struct vhost_mdev *m) > +{ > + struct mdev_device *mdev = m->mdev; > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + > + ops->set_status(mdev, 0); > +} > + > +static long vhost_mdev_get_device_id(struct vhost_mdev *m, u8 __user *argp) > +{ > + struct mdev_device *mdev = m->mdev; > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + u32 device_id; > + > + device_id = ops->get_device_id(mdev); > + > + if (copy_to_user(argp, &device_id, sizeof(device_id))) > + return -EFAULT; > + > + return 0; > +} > + > +static long vhost_mdev_get_status(struct vhost_mdev *m, u8 __user *statusp) > +{ > + struct mdev_device *mdev = m->mdev; > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + u8 status; > + > + status = ops->get_status(mdev); > + > + if (copy_to_user(statusp, &status, sizeof(status))) > + return -EFAULT; > + > + return 0; > +} > + > +static long vhost_mdev_set_status(struct vhost_mdev *m, u8 __user *statusp) > +{ > + struct mdev_device *mdev = m->mdev; > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + u8 status; > + > + if (copy_from_user(&status, statusp, sizeof(status))) > + return -EFAULT; > + > + /* > + * Userspace shouldn't remove status bits unless reset the > + * status to 0. > + */ > + if (status != 0 && (ops->get_status(mdev) & ~status) != 0) > + return -EINVAL; > + > + ops->set_status(mdev, status); > + > + return 0; > +} > + > +static int vhost_mdev_config_validate(struct vhost_mdev *m, > + struct vhost_mdev_config *c) > +{ > + long size = 0; > + > + switch (m->virtio_id) { > + case VIRTIO_ID_NET: > + size = sizeof(struct virtio_net_config); > + break; > + } > + > + if (c->len == 0) > + return -EINVAL; > + > + if (c->len > size - c->off) > + return -E2BIG; > + > + return 0; > +} > + > +static long vhost_mdev_get_config(struct vhost_mdev *m, > + struct vhost_mdev_config __user *c) > +{ > + struct mdev_device *mdev = m->mdev; > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + struct vhost_mdev_config config; > + unsigned long size = offsetof(struct vhost_mdev_config, buf); > + u8 *buf; > + > + if (copy_from_user(&config, c, size)) > + return -EFAULT; > + if (vhost_mdev_config_validate(m, &config)) > + return -EINVAL; > + buf = kvzalloc(config.len, GFP_KERNEL); > + if (!buf) > + return -ENOMEM; > + > + ops->get_config(mdev, config.off, buf, config.len); > + > + if (copy_to_user(c->buf, buf, config.len)) { > + kvfree(buf); > + return -EFAULT; > + } > + > + kvfree(buf); > + return 0; > +} > + > +static long vhost_mdev_set_config(struct vhost_mdev *m, > + struct vhost_mdev_config __user *c) > +{ > + struct mdev_device *mdev = m->mdev; > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + struct vhost_mdev_config config; > + unsigned long size = offsetof(struct vhost_mdev_config, buf); > + u8 *buf; > + > + if (copy_from_user(&config, c, size)) > + return -EFAULT; > + if (vhost_mdev_config_validate(m, &config)) > + return -EINVAL; > + buf = kvzalloc(config.len, GFP_KERNEL); > + if (!buf) > + return -ENOMEM; > + > + if (copy_from_user(buf, c->buf, config.len)) { > + kvfree(buf); > + return -EFAULT; > + } > + > + ops->set_config(mdev, config.off, buf, config.len); > + > + kvfree(buf); > + return 0; > +} > + > +static long vhost_mdev_get_features(struct vhost_mdev *m, u64 __user *featurep) > +{ > + struct mdev_device *mdev = m->mdev; > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + u64 features; > + > + features = ops->get_features(mdev); > + features &= vhost_mdev_features[m->virtio_id]; > + > + if (copy_to_user(featurep, &features, sizeof(features))) > + return -EFAULT; > + > + return 0; > +} > + > +static long vhost_mdev_set_features(struct vhost_mdev *m, u64 __user *featurep) > +{ > + struct mdev_device *mdev = m->mdev; > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + u64 features; > + > + /* > + * It's not allowed to change the features after they have > + * been negotiated. > + */ > + if (ops->get_status(mdev) & VIRTIO_CONFIG_S_FEATURES_OK) > + return -EBUSY; > + > + if (copy_from_user(&features, featurep, sizeof(features))) > + return -EFAULT; > + > + if (features & ~vhost_mdev_features[m->virtio_id]) > + return -EINVAL; > + > + if (ops->set_features(mdev, features)) > + return -EINVAL; > + > + return 0; > +} > + > +static long vhost_mdev_get_vring_num(struct vhost_mdev *m, u16 __user *argp) > +{ > + struct mdev_device *mdev = m->mdev; > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + u16 num; > + > + num = ops->get_vq_num_max(mdev); > + > + if (copy_to_user(argp, &num, sizeof(num))) > + return -EFAULT; > + > + return 0; > +} > + > +static long vhost_mdev_vring_ioctl(struct vhost_mdev *m, unsigned int cmd, > + void __user *argp) > +{ > + struct mdev_device *mdev = m->mdev; > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + struct virtio_mdev_callback cb; > + struct vhost_virtqueue *vq; > + struct vhost_vring_state s; > + u8 status; > + u32 idx; > + long r; > + > + r = get_user(idx, (u32 __user *)argp); > + if (r < 0) > + return r; > + if (idx >= m->nvqs) > + return -ENOBUFS; > + > + idx = array_index_nospec(idx, m->nvqs); > + vq = &m->vqs[idx]; > + > + status = ops->get_status(mdev); > + > + /* > + * It's not allowed to detect and program vqs before > + * features negotiation or after enabling driver. > + */ > + if (!(status & VIRTIO_CONFIG_S_FEATURES_OK) || > + (status & VIRTIO_CONFIG_S_DRIVER_OK)) > + return -EBUSY; > + > + if (cmd == VHOST_MDEV_SET_VRING_ENABLE) { > + if (copy_from_user(&s, argp, sizeof(s))) > + return -EFAULT; > + ops->set_vq_ready(mdev, idx, s.num); > + return 0; > + } > + > + /* > + * It's not allowed to detect and program vqs with > + * vqs enabled. > + */ > + if (ops->get_vq_ready(mdev, idx)) > + return -EBUSY; > + > + if (cmd == VHOST_GET_VRING_BASE) > + vq->last_avail_idx = ops->get_vq_state(m->mdev, idx); > + > + r = vhost_vring_ioctl(&m->dev, cmd, argp); > + if (r) > + return r; > + > + switch (cmd) { > + case VHOST_SET_VRING_ADDR: > + /* > + * In vhost-mdev, the ring addresses set by userspace should > + * be the DMA addresses within the VFIO container/group. > + */ > + if (ops->set_vq_address(mdev, idx, (u64)vq->desc, > + (u64)vq->avail, (u64)vq->used)) > + r = -EINVAL; > + break; > + > + case VHOST_SET_VRING_BASE: > + if (ops->set_vq_state(mdev, idx, vq->last_avail_idx)) > + r = -EINVAL; > + break; > + > + case VHOST_SET_VRING_CALL: > + if (vq->call_ctx) { > + cb.callback = vhost_mdev_virtqueue_cb; > + cb.private = vq; > + } else { > + cb.callback = NULL; > + cb.private = NULL; > + } > + ops->set_vq_cb(mdev, idx, &cb); > + break; > + > + case VHOST_SET_VRING_NUM: > + ops->set_vq_num(mdev, idx, vq->num); > + break; > + } > + > + return r; > +} > + > +static int vhost_mdev_open(void *device_data) > +{ > + struct vhost_mdev *m = device_data; > + struct vhost_dev *dev; > + struct vhost_virtqueue **vqs; > + int nvqs, i, r; > + > + if (!try_module_get(THIS_MODULE)) > + return -ENODEV; > + > + mutex_lock(&m->mutex); > + > + if (m->opened) { > + r = -EBUSY; > + goto err; > + } > + > + nvqs = m->nvqs; > + vhost_mdev_reset(m); > + > + vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL); > + if (!vqs) { > + r = -ENOMEM; > + goto err; > + } > + > + dev = &m->dev; > + for (i = 0; i < nvqs; i++) { > + vqs[i] = &m->vqs[i]; > + vqs[i]->handle_kick = handle_vq_kick; > + } > + vhost_dev_init(dev, vqs, nvqs, 0, 0, 0); > + m->opened = true; > + mutex_unlock(&m->mutex); > + > + return 0; > + > +err: > + mutex_unlock(&m->mutex); > + module_put(THIS_MODULE); > + return r; > +} > + > +static void vhost_mdev_release(void *device_data) > +{ > + struct vhost_mdev *m = device_data; > + > + mutex_lock(&m->mutex); > + vhost_mdev_reset(m); > + vhost_dev_stop(&m->dev); > + vhost_dev_cleanup(&m->dev); > + > + kfree(m->dev.vqs); > + m->opened = false; > + mutex_unlock(&m->mutex); > + module_put(THIS_MODULE); > +} > + > +static long vhost_mdev_unlocked_ioctl(void *device_data, > + unsigned int cmd, unsigned long arg) > +{ > + struct vhost_mdev *m = device_data; > + void __user *argp = (void __user *)arg; > + long r; > + > + mutex_lock(&m->mutex); > + > + switch (cmd) { > + case VHOST_MDEV_GET_DEVICE_ID: > + r = vhost_mdev_get_device_id(m, argp); > + break; > + case VHOST_MDEV_GET_STATUS: > + r = vhost_mdev_get_status(m, argp); > + break; > + case VHOST_MDEV_SET_STATUS: > + r = vhost_mdev_set_status(m, argp); > + break; > + case VHOST_MDEV_GET_CONFIG: > + r = vhost_mdev_get_config(m, argp); > + break; > + case VHOST_MDEV_SET_CONFIG: > + r = vhost_mdev_set_config(m, argp); > + break; > + case VHOST_GET_FEATURES: > + r = vhost_mdev_get_features(m, argp); > + break; > + case VHOST_SET_FEATURES: > + r = vhost_mdev_set_features(m, argp); > + break; > + case VHOST_MDEV_GET_VRING_NUM: > + r = vhost_mdev_get_vring_num(m, argp); > + break; > + case VHOST_SET_LOG_BASE: > + case VHOST_SET_LOG_FD: > + r = -ENOTSUPP; > + break; > + default: > + mutex_lock(&m->dev.mutex); > + r = vhost_dev_ioctl(&m->dev, cmd, argp); > + if (r == -ENOIOCTLCMD) > + r = vhost_mdev_vring_ioctl(m, cmd, argp); > + mutex_unlock(&m->dev.mutex); > + break; > + } > + > + mutex_unlock(&m->mutex); > + return r; > +} > + > +static const struct vfio_device_ops vfio_vhost_mdev_dev_ops = { > + .name = "vfio-vhost-mdev", > + .open = vhost_mdev_open, > + .release = vhost_mdev_release, > + .ioctl = vhost_mdev_unlocked_ioctl, > +}; > + > +static int vhost_mdev_probe(struct device *dev) > +{ > + struct mdev_device *mdev = mdev_from_dev(dev); > + const struct mdev_virtio_device_ops *ops = mdev_get_vhost_ops(mdev); > + struct vhost_mdev *m; > + int nvqs, r; > + > + /* Currently, we only accept the network devices. */ > + if (ops->get_device_id(mdev) != VIRTIO_ID_NET) > + return -ENOTSUPP; > + > + m = devm_kzalloc(dev, sizeof(*m), GFP_KERNEL | __GFP_RETRY_MAYFAIL); > + if (!m) > + return -ENOMEM; > + > + nvqs = VHOST_MDEV_VQ_MAX; > + > + m->vqs = devm_kmalloc_array(dev, nvqs, sizeof(struct vhost_virtqueue), > + GFP_KERNEL); > + if (!m->vqs) > + return -ENOMEM; > + > + mutex_init(&m->mutex); > + > + m->mdev = mdev; > + m->nvqs = nvqs; > + m->virtio_id = ops->get_device_id(mdev); > + > + r = vfio_add_group_dev(dev, &vfio_vhost_mdev_dev_ops, m); > + if (r) { > + mutex_destroy(&m->mutex); > + return r; > + } > + > + return 0; > +} > + > +static void vhost_mdev_remove(struct device *dev) > +{ > + struct vhost_mdev *m; > + > + m = vfio_del_group_dev(dev); > + mutex_destroy(&m->mutex); > +} > + > +static const struct mdev_class_id vhost_mdev_match[] = { > + { MDEV_CLASS_ID_VHOST }, > + { 0 }, > +}; > +MODULE_DEVICE_TABLE(mdev, vhost_mdev_match); > + > +static struct mdev_driver vhost_mdev_driver = { > + .name = "vhost_mdev", > + .probe = vhost_mdev_probe, > + .remove = vhost_mdev_remove, > + .id_table = vhost_mdev_match, > +}; > + > +static int __init vhost_mdev_init(void) > +{ > + return mdev_register_driver(&vhost_mdev_driver, THIS_MODULE); > +} > +module_init(vhost_mdev_init); > + > +static void __exit vhost_mdev_exit(void) > +{ > + mdev_unregister_driver(&vhost_mdev_driver); > +} > +module_exit(vhost_mdev_exit); > + > +MODULE_VERSION("0.0.1"); > +MODULE_LICENSE("GPL v2"); > +MODULE_AUTHOR("Intel Corporation"); > +MODULE_DESCRIPTION("Mediated device based accelerator for virtio"); > diff --git a/include/linux/mdev.h b/include/linux/mdev.h > index f3d75a60c2b5..8af7fb9e0149 100644 > --- a/include/linux/mdev.h > +++ b/include/linux/mdev.h > @@ -117,6 +117,10 @@ void mdev_set_virtio_ops(struct mdev_device *mdev, > const struct mdev_virtio_device_ops *virtio_ops); > const struct mdev_virtio_device_ops * > mdev_get_virtio_ops(struct mdev_device *mdev); > +void mdev_set_vhost_ops(struct mdev_device *mdev, > + const struct mdev_virtio_device_ops *vhost_ops); > +const struct mdev_virtio_device_ops * > +mdev_get_vhost_ops(struct mdev_device *mdev); > > extern struct bus_type mdev_bus_type; > > @@ -133,6 +137,7 @@ struct mdev_device *mdev_from_dev(struct device *dev); > enum { > MDEV_CLASS_ID_VFIO = 1, > MDEV_CLASS_ID_VIRTIO = 2, > + MDEV_CLASS_ID_VHOST = 3, > /* New entries must be added here */ > }; > > diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h > index 40d028eed645..a7e862245bb4 100644 > --- a/include/uapi/linux/vhost.h > +++ b/include/uapi/linux/vhost.h > @@ -116,4 +116,25 @@ > #define VHOST_VSOCK_SET_GUEST_CID _IOW(VHOST_VIRTIO, 0x60, __u64) > #define VHOST_VSOCK_SET_RUNNING _IOW(VHOST_VIRTIO, 0x61, int) > > +/* VHOST_MDEV specific defines */ > + > +/* Get the device id. The device ids follow the same definition of > + * the device id defined in virtio-spec. */ > +#define VHOST_MDEV_GET_DEVICE_ID _IOR(VHOST_VIRTIO, 0x70, __u32) > +/* Get and set the status. The status bits follow the same definition > + * of the device status defined in virtio-spec. */ > +#define VHOST_MDEV_GET_STATUS _IOR(VHOST_VIRTIO, 0x71, __u8) > +#define VHOST_MDEV_SET_STATUS _IOW(VHOST_VIRTIO, 0x72, __u8) > +/* Get and set the device config. The device config follows the same > + * definition of the device config defined in virtio-spec. */ > +#define VHOST_MDEV_GET_CONFIG _IOR(VHOST_VIRTIO, 0x73, \ > + struct vhost_mdev_config) > +#define VHOST_MDEV_SET_CONFIG _IOW(VHOST_VIRTIO, 0x74, \ > + struct vhost_mdev_config) > +/* Enable/disable the ring. */ > +#define VHOST_MDEV_SET_VRING_ENABLE _IOW(VHOST_VIRTIO, 0x75, \ > + struct vhost_vring_state) > +/* Get the max ring size. */ > +#define VHOST_MDEV_GET_VRING_NUM _IOR(VHOST_VIRTIO, 0x76, __u16) > + > #endif > diff --git a/include/uapi/linux/vhost_types.h b/include/uapi/linux/vhost_types.h > index c907290ff065..7b105d0b2fb9 100644 > --- a/include/uapi/linux/vhost_types.h > +++ b/include/uapi/linux/vhost_types.h > @@ -119,6 +119,14 @@ struct vhost_scsi_target { > unsigned short reserved; > }; > > +/* VHOST_MDEV specific definitions */ > + > +struct vhost_mdev_config { > + __u32 off; > + __u32 len; > + __u8 buf[0]; > +}; > + > /* Feature bits */ > /* Log all write descriptors. Can be changed while device is active. */ > #define VHOST_F_LOG_ALL 26 > -- > 2.23.0