On 2019/10/30 下午1:52, Tiwei Bie wrote: > On Wed, Oct 30, 2019 at 09:55:57AM +0800, Jason Wang wrote: >> On 2019/10/29 下午6:07, 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 of this device, userspace can use vhost ioctls >>> to setup the backend. >> >> Hi Tiwei: >> >> The patch looks good overall, just few comments & nits. > Thanks for the review! I do appreciate it. You're welcome :) > >> >>> Signed-off-by: Tiwei Bie <tiwei.bie@xxxxxxxxx> >>> --- >>> This patch depends on below series: >>> https://lkml.org/lkml/2019/10/23/614 >>> >>> 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 | 20 ++ >>> drivers/vfio/mdev/mdev_private.h | 1 + >>> drivers/vhost/Kconfig | 12 + >>> drivers/vhost/Makefile | 3 + >>> drivers/vhost/mdev.c | 554 +++++++++++++++++++++++++++++++ >>> include/linux/mdev.h | 5 + >>> include/uapi/linux/vhost.h | 18 + >>> include/uapi/linux/vhost_types.h | 8 + >>> 8 files changed, 621 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 9b00c3513120..3cfd787d605c 100644 >>> --- a/drivers/vfio/mdev/mdev_core.c >>> +++ b/drivers/vfio/mdev/mdev_core.c >>> @@ -96,6 +96,26 @@ 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 virtio_mdev_device_ops *vhost_ops) >>> +{ >>> + mdev_set_class(mdev, MDEV_CLASS_ID_VHOST); >>> + mdev->vhost_ops = vhost_ops; >>> +} >>> +EXPORT_SYMBOL(mdev_set_vhost_ops); >>> + >>> +/* Get the vhost device ops for the mdev device. */ >>> +const struct virtio_mdev_device_ops * >>> +mdev_get_vhost_ops(struct mdev_device *mdev) >>> +{ >>> + WARN_ON(mdev->class_id != MDEV_CLASS_ID_VHOST); >>> + return mdev->vhost_ops; >>> +} >>> +EXPORT_SYMBOL(mdev_get_vhost_ops); >>> + >>> struct device *mdev_dev(struct mdev_device *mdev) >>> { >>> return &mdev->dev; >>> diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h >>> index 7b47890c34e7..5597c846e52f 100644 >>> --- a/drivers/vfio/mdev/mdev_private.h >>> +++ b/drivers/vfio/mdev/mdev_private.h >>> @@ -40,6 +40,7 @@ struct mdev_device { >>> union { >>> const struct vfio_mdev_device_ops *vfio_ops; >>> const struct virtio_mdev_device_ops *virtio_ops; >>> + const struct virtio_mdev_device_ops *vhost_ops; >>> }; >>> }; >>> >>> 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..35b2fb33e686 >>> --- /dev/null >>> +++ b/drivers/vhost/mdev.c >>> @@ -0,0 +1,554 @@ >>> +// SPDX-License-Identifier: GPL-2.0 >>> +/* >>> + * Vhost driver for mediated device based backends. >>> + * >>> + * Copyright (C) 2018-2019 Intel Corporation. >>> + * >>> + * Author: Tiwei Bie <tiwei.bie@xxxxxxxxx> >>> + * >>> + * 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 <linux/kernel.h> >>> +#include <linux/module.h> >>> +#include <linux/mdev.h> >>> +#include <linux/vfio.h> >>> +#include <linux/vhost.h> >>> +#include <linux/virtio_net.h> >>> +#include <linux/virtio_mdev_ops.h> >>> + >>> +#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 virtio_mdev_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 virtio_mdev_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 virtio_mdev_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; >>> +} >> >> I believe we need get_vendor_id() as well? > Currently, there is no official way for vendors to do vendor > specific extensions in vhost-mdev yet. It might be better to > add this ioctl when we support this. Good point. > >> >>> + >>> +static long vhost_mdev_get_status(struct vhost_mdev *m, u8 __user *statusp) >>> +{ >>> + struct mdev_device *mdev = m->mdev; >>> + const struct virtio_mdev_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 virtio_mdev_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->off >= size || c->len > size || c->off + c->len > size) >>> + 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 virtio_mdev_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; >> >> I think it's better to let the parent to do such validation. Especially >> consider that the size of config may depend on feature (e.g MQ). > Above check is just a basic sanity check to make sure > that e.g. we won't alloc a huge amount of memory. I see. > >> >>> + 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 virtio_mdev_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 virtio_mdev_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 virtio_mdev_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 virtio_mdev_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 virtio_mdev_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; >>> + >>> + 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; >>> + >>> + vq = &m->vqs[idx]; >>> + >>> + 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 = -ENODEV; >> >> Nit: It looks to me that we need expose alignment of vq to userspace >> (get_vq_align()). > Guest drivers are using (maybe hardcoded) alignments based > on the alignment requirements defined in the spec. It might > be better to let backends follow the same standard for the > compatibility. Ok. Thanks > >> Thanks >> >> >>> + break; >>> + >>> + case VHOST_SET_VRING_BASE: >>> + if (ops->set_vq_state(mdev, idx, vq->last_avail_idx)) >>> + r = -ENODEV; >>> + 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; >>> + default: >>> + /* >>> + * VHOST_SET_MEM_TABLE, VHOST_SET_LOG_BASE, and >>> + * VHOST_SET_LOG_FD are not used yet. >>> + */ >>> + r = vhost_dev_ioctl(&m->dev, cmd, argp); >>> + if (r == -ENOIOCTLCMD) >>> + r = vhost_mdev_vring_ioctl(m, cmd, argp); >>> + } >>> + >>> + 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 virtio_mdev_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; >>> + >>> + if (ops->get_mdev_features(mdev) != VIRTIO_MDEV_F_VERSION_1) >>> + 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 9b69b0bbebfd..3e1e03926355 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 virtio_mdev_device_ops *virtio_ops); >>> const struct virtio_mdev_device_ops * >>> mdev_get_virtio_ops(struct mdev_device *mdev); >>> +void mdev_set_vhost_ops(struct mdev_device *mdev, >>> + const struct virtio_mdev_device_ops *vhost_ops); >>> +const struct virtio_mdev_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..061a2824a1b3 100644 >>> --- a/include/uapi/linux/vhost.h >>> +++ b/include/uapi/linux/vhost.h >>> @@ -116,4 +116,22 @@ >>> #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 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
