[PATCH] vhost: introduce vDPA based backend
From: Tiwei Bie
Date: Thu Jan 30 2020 - 22:37:41 EST
This patch introduces a vDPA based vhost backend. This
backend is built on top of the same interface defined
in virtio-vDPA and provides a generic vhost interface
for userspace to accelerate the virtio devices in guest.
This backend is implemented as a vDPA device driver on
top of the same ops used in virtio-vDPA. It will create
char device entry named vhost-vdpa/$vdpa_device_index
for userspace to use. Userspace can use vhost ioctls on
top of this char device to setup the backend.
Signed-off-by: Tiwei Bie <tiwei.bie@xxxxxxxxx>
---
This patch depends on below series:
https://lkml.org/lkml/2020/1/16/353
Please note that _SET_MEM_TABLE isn't fully supported yet.
Comments would be appreciated!
Changes since last patch (https://lkml.org/lkml/2019/11/18/1068)
- Switch to the vDPA bus;
- Switch to vhost's own chardev;
drivers/vhost/Kconfig | 12 +
drivers/vhost/Makefile | 3 +
drivers/vhost/vdpa.c | 705 +++++++++++++++++++++++++++++++
include/uapi/linux/vhost.h | 21 +
include/uapi/linux/vhost_types.h | 8 +
5 files changed, 749 insertions(+)
create mode 100644 drivers/vhost/vdpa.c
diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index f21c45aa5e07..13e6a94d0243 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -34,6 +34,18 @@ config VHOST_VSOCK
To compile this driver as a module, choose M here: the module will be called
vhost_vsock.
+config VHOST_VDPA
+ tristate "Vhost driver for vDPA based backend"
+ depends on EVENTFD && VDPA
+ select VHOST
+ default n
+ ---help---
+ This kernel module can be loaded in host kernel to accelerate
+ guest virtio devices with the vDPA based backends.
+
+ To compile this driver as a module, choose M here: the module
+ will be called vhost_vdpa.
+
config VHOST
tristate
depends on VHOST_IOTLB
diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile
index df99756fbb26..a65e9f4a2c0a 100644
--- a/drivers/vhost/Makefile
+++ b/drivers/vhost/Makefile
@@ -10,6 +10,9 @@ vhost_vsock-y := vsock.o
obj-$(CONFIG_VHOST_RING) += vringh.o
+obj-$(CONFIG_VHOST_VDPA) += vhost_vdpa.o
+vhost_vdpa-y := vdpa.o
+
obj-$(CONFIG_VHOST) += vhost.o
obj-$(CONFIG_VHOST_IOTLB) += vhost_iotlb.o
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
new file mode 100644
index 000000000000..631d994d37ac
--- /dev/null
+++ b/drivers/vhost/vdpa.c
@@ -0,0 +1,705 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018-2020 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/cdev.h>
+#include <linux/device.h>
+#include <linux/uuid.h>
+#include <linux/vdpa.h>
+#include <linux/nospec.h>
+#include <linux/vhost.h>
+#include <linux/virtio_net.h>
+
+#include "vhost.h"
+
+enum {
+ VHOST_VDPA_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_VDPA_NET_FEATURES = VHOST_VDPA_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_VDPA_VQ_MAX 2
+
+struct vhost_vdpa {
+ /* The lock is to protect this structure. */
+ struct mutex mutex;
+ struct vhost_dev vdev;
+ struct vhost_virtqueue *vqs;
+ struct vdpa_device *vdpa;
+ struct device *dev;
+ atomic_t opened;
+ int nvqs;
+ int virtio_id;
+ int minor;
+};
+
+static struct {
+ /* The lock is to protect this structure. */
+ struct mutex mutex;
+ struct class *class;
+ struct idr idr;
+ struct cdev cdev;
+ dev_t devt;
+ wait_queue_head_t release_q;
+} vhost_vdpa;
+
+static const u64 vhost_vdpa_features[] = {
+ [VIRTIO_ID_NET] = VHOST_VDPA_NET_FEATURES,
+};
+
+static int vhost_vdpa_alloc_minor(struct vhost_vdpa *v)
+{
+ return idr_alloc(&vhost_vdpa.idr, v, 0, MINORMASK + 1,
+ GFP_KERNEL);
+}
+
+static void vhost_vdpa_free_minor(int minor)
+{
+ idr_remove(&vhost_vdpa.idr, minor);
+}
+
+static struct vhost_vdpa *vhost_vdpa_get_from_minor(int minor)
+{
+ struct vhost_vdpa *v;
+
+ mutex_lock(&vhost_vdpa.mutex);
+ v = idr_find(&vhost_vdpa.idr, minor);
+ mutex_unlock(&vhost_vdpa.mutex);
+
+ return v;
+}
+
+static void handle_vq_kick(struct vhost_work *work)
+{
+ struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
+ poll.work);
+ struct vhost_vdpa *v = container_of(vq->dev, struct vhost_vdpa, vdev);
+ const struct vdpa_config_ops *ops = v->vdpa->config;
+
+ ops->kick_vq(v->vdpa, vq - v->vqs);
+}
+
+static irqreturn_t vhost_vdpa_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_vdpa_reset(struct vhost_vdpa *v)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+
+ ops->set_status(vdpa, 0);
+}
+
+static long vhost_vdpa_get_device_id(struct vhost_vdpa *v, u8 __user *argp)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ u32 device_id;
+
+ device_id = ops->get_device_id(vdpa);
+
+ if (copy_to_user(argp, &device_id, sizeof(device_id)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static long vhost_vdpa_get_status(struct vhost_vdpa *v, u8 __user *statusp)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ u8 status;
+
+ status = ops->get_status(vdpa);
+
+ if (copy_to_user(statusp, &status, sizeof(status)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ 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(vdpa) & ~status) != 0)
+ return -EINVAL;
+
+ ops->set_status(vdpa, status);
+
+ return 0;
+}
+
+static int vhost_vdpa_config_validate(struct vhost_vdpa *v,
+ struct vhost_vdpa_config *c)
+{
+ long size = 0;
+
+ switch (v->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_vdpa_get_config(struct vhost_vdpa *v,
+ struct vhost_vdpa_config __user *c)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ struct vhost_vdpa_config config;
+ unsigned long size = offsetof(struct vhost_vdpa_config, buf);
+ u8 *buf;
+
+ if (copy_from_user(&config, c, size))
+ return -EFAULT;
+ if (vhost_vdpa_config_validate(v, &config))
+ return -EINVAL;
+ buf = kvzalloc(config.len, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ ops->get_config(vdpa, 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_vdpa_set_config(struct vhost_vdpa *v,
+ struct vhost_vdpa_config __user *c)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ struct vhost_vdpa_config config;
+ unsigned long size = offsetof(struct vhost_vdpa_config, buf);
+ u8 *buf;
+
+ if (copy_from_user(&config, c, size))
+ return -EFAULT;
+ if (vhost_vdpa_config_validate(v, &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(vdpa, config.off, buf, config.len);
+
+ kvfree(buf);
+ return 0;
+}
+
+static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ u64 features;
+
+ features = ops->get_features(vdpa);
+ features &= vhost_vdpa_features[v->virtio_id];
+
+ if (copy_to_user(featurep, &features, sizeof(features)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static long vhost_vdpa_set_features(struct vhost_vdpa *v, u64 __user *featurep)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ u64 features;
+
+ /*
+ * It's not allowed to change the features after they have
+ * been negotiated.
+ */
+ if (ops->get_status(vdpa) & VIRTIO_CONFIG_S_FEATURES_OK)
+ return -EBUSY;
+
+ if (copy_from_user(&features, featurep, sizeof(features)))
+ return -EFAULT;
+
+ if (features & ~vhost_vdpa_features[v->virtio_id])
+ return -EINVAL;
+
+ if (ops->set_features(vdpa, features))
+ return -EINVAL;
+
+ return 0;
+}
+
+static long vhost_vdpa_get_vring_num(struct vhost_vdpa *v, u16 __user *argp)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ u16 num;
+
+ num = ops->get_vq_num_max(vdpa);
+
+ if (copy_to_user(argp, &num, sizeof(num)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
+ void __user *argp)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ struct vdpa_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 >= v->nvqs)
+ return -ENOBUFS;
+
+ idx = array_index_nospec(idx, v->nvqs);
+ vq = &v->vqs[idx];
+
+ status = ops->get_status(vdpa);
+
+ /*
+ * 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_VDPA_SET_VRING_ENABLE) {
+ if (copy_from_user(&s, argp, sizeof(s)))
+ return -EFAULT;
+ ops->set_vq_ready(vdpa, idx, s.num);
+ return 0;
+ }
+
+ /*
+ * It's not allowed to detect and program vqs with
+ * vqs enabled.
+ */
+ if (ops->get_vq_ready(vdpa, idx))
+ return -EBUSY;
+
+ if (cmd == VHOST_GET_VRING_BASE)
+ vq->last_avail_idx = ops->get_vq_state(v->vdpa, idx);
+
+ r = vhost_vring_ioctl(&v->vdev, cmd, argp);
+ if (r)
+ return r;
+
+ switch (cmd) {
+ case VHOST_SET_VRING_ADDR:
+ if (ops->set_vq_address(vdpa, idx, (u64)vq->desc,
+ (u64)vq->avail, (u64)vq->used))
+ r = -EINVAL;
+ break;
+
+ case VHOST_SET_VRING_BASE:
+ if (ops->set_vq_state(vdpa, idx, vq->last_avail_idx))
+ r = -EINVAL;
+ break;
+
+ case VHOST_SET_VRING_CALL:
+ if (vq->call_ctx) {
+ cb.callback = vhost_vdpa_virtqueue_cb;
+ cb.private = vq;
+ } else {
+ cb.callback = NULL;
+ cb.private = NULL;
+ }
+ ops->set_vq_cb(vdpa, idx, &cb);
+ break;
+
+ case VHOST_SET_VRING_NUM:
+ ops->set_vq_num(vdpa, idx, vq->num);
+ break;
+ }
+
+ return r;
+}
+
+static long vhost_vdpa_do_dma_mapping(struct vhost_vdpa *v)
+{
+ /* TODO: fix this */
+ return -ENOTSUPP;
+}
+
+static int vhost_vdpa_open(struct inode *inode, struct file *filep)
+{
+ struct vhost_vdpa *v;
+ struct vhost_dev *dev;
+ struct vhost_virtqueue **vqs;
+ int nvqs, i, r, opened;
+
+ v = vhost_vdpa_get_from_minor(iminor(inode));
+ if (!v)
+ return -ENODEV;
+
+ opened = atomic_cmpxchg(&v->opened, 0, 1);
+ if (opened) {
+ r = -EBUSY;
+ goto err;
+ }
+
+ nvqs = v->nvqs;
+ vhost_vdpa_reset(v);
+
+ vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
+ if (!vqs) {
+ r = -ENOMEM;
+ goto err;
+ }
+
+ dev = &v->vdev;
+ for (i = 0; i < nvqs; i++) {
+ vqs[i] = &v->vqs[i];
+ vqs[i]->handle_kick = handle_vq_kick;
+ }
+ vhost_dev_init(dev, vqs, nvqs, 0, 0, 0);
+
+ filep->private_data = v;
+
+ return 0;
+
+err:
+ atomic_dec(&v->opened);
+ return r;
+}
+
+static int vhost_vdpa_release(struct inode *inode, struct file *filep)
+{
+ struct vhost_vdpa *v = filep->private_data;
+
+ mutex_lock(&v->mutex);
+ filep->private_data = NULL;
+ vhost_vdpa_reset(v);
+ vhost_dev_stop(&v->vdev);
+ vhost_dev_cleanup(&v->vdev);
+ kfree(v->vdev.vqs);
+ mutex_unlock(&v->mutex);
+
+ atomic_dec(&v->opened);
+ wake_up(&vhost_vdpa.release_q);
+
+ return 0;
+}
+
+static long vhost_vdpa_unlocked_ioctl(struct file *filep,
+ unsigned int cmd, unsigned long arg)
+{
+ struct vhost_vdpa *v = filep->private_data;
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ void __user *argp = (void __user *)arg;
+ long r;
+
+ mutex_lock(&v->mutex);
+
+ switch (cmd) {
+ case VHOST_VDPA_GET_DEVICE_ID:
+ r = vhost_vdpa_get_device_id(v, argp);
+ break;
+ case VHOST_VDPA_GET_STATUS:
+ r = vhost_vdpa_get_status(v, argp);
+ break;
+ case VHOST_VDPA_SET_STATUS:
+ r = vhost_vdpa_set_status(v, argp);
+ break;
+ case VHOST_VDPA_GET_CONFIG:
+ r = vhost_vdpa_get_config(v, argp);
+ break;
+ case VHOST_VDPA_SET_CONFIG:
+ r = vhost_vdpa_set_config(v, argp);
+ break;
+ case VHOST_GET_FEATURES:
+ r = vhost_vdpa_get_features(v, argp);
+ break;
+ case VHOST_SET_FEATURES:
+ r = vhost_vdpa_set_features(v, argp);
+ break;
+ case VHOST_VDPA_GET_VRING_NUM:
+ r = vhost_vdpa_get_vring_num(v, argp);
+ break;
+ case VHOST_SET_LOG_BASE:
+ case VHOST_SET_LOG_FD:
+ r = -ENOIOCTLCMD;
+ break;
+ default:
+ mutex_lock(&v->vdev.mutex);
+ r = vhost_dev_ioctl(&v->vdev, cmd, argp);
+ if (r == -ENOIOCTLCMD)
+ r = vhost_vdpa_vring_ioctl(v, cmd, argp);
+ mutex_unlock(&v->vdev.mutex);
+ break;
+ }
+
+ if (r)
+ goto out;
+
+ switch (cmd) {
+ case VHOST_SET_MEM_TABLE:
+ if (ops->set_map)
+ r = ops->set_map(vdpa, v->vdev.umem);
+ else
+ r = vhost_vdpa_do_dma_mapping(v);
+ break;
+ }
+
+out:
+ mutex_unlock(&v->mutex);
+ return r;
+}
+
+static const struct file_operations vhost_vdpa_fops = {
+ .owner = THIS_MODULE,
+ .open = vhost_vdpa_open,
+ .release = vhost_vdpa_release,
+ .unlocked_ioctl = vhost_vdpa_unlocked_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+};
+
+static int vhost_vdpa_probe(struct device *dev)
+{
+ struct vdpa_device *vdpa = dev_to_vdpa(dev);
+ const struct vdpa_config_ops *ops = vdpa->config;
+ struct vhost_vdpa *v;
+ struct device *d;
+ int minor, nvqs;
+ int r;
+
+ /* Currently, we only accept the network devices. */
+ if (ops->get_device_id(vdpa) != VIRTIO_ID_NET) {
+ r = -ENOTSUPP;
+ goto err;
+ }
+
+ v = kzalloc(sizeof(*v), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
+ if (!v) {
+ r = -ENOMEM;
+ goto err;
+ }
+
+ nvqs = VHOST_VDPA_VQ_MAX;
+
+ v->vqs = kmalloc_array(nvqs, sizeof(struct vhost_virtqueue),
+ GFP_KERNEL);
+ if (!v->vqs) {
+ r = -ENOMEM;
+ goto err_alloc_vqs;
+ }
+
+ mutex_init(&v->mutex);
+ atomic_set(&v->opened, 0);
+
+ v->vdpa = vdpa;
+ v->nvqs = nvqs;
+ v->virtio_id = ops->get_device_id(vdpa);
+
+ mutex_lock(&vhost_vdpa.mutex);
+
+ minor = vhost_vdpa_alloc_minor(v);
+ if (minor < 0) {
+ r = minor;
+ goto err_alloc_minor;
+ }
+
+ d = device_create(vhost_vdpa.class, NULL,
+ MKDEV(MAJOR(vhost_vdpa.devt), minor),
+ v, "%d", vdpa->index);
+ if (IS_ERR(d)) {
+ r = PTR_ERR(d);
+ goto err_device_create;
+ }
+
+ mutex_unlock(&vhost_vdpa.mutex);
+
+ v->dev = d;
+ v->minor = minor;
+ dev_set_drvdata(dev, v);
+
+ return 0;
+
+err_device_create:
+ vhost_vdpa_free_minor(minor);
+err_alloc_minor:
+ mutex_unlock(&vhost_vdpa.mutex);
+ kfree(v->vqs);
+err_alloc_vqs:
+ kfree(v);
+err:
+ return r;
+}
+
+static void vhost_vdpa_remove(struct device *dev)
+{
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
+ struct vhost_vdpa *v = dev_get_drvdata(dev);
+ int opened;
+
+ add_wait_queue(&vhost_vdpa.release_q, &wait);
+
+ do {
+ opened = atomic_cmpxchg(&v->opened, 0, 1);
+ if (!opened)
+ break;
+ wait_woken(&wait, TASK_UNINTERRUPTIBLE, HZ * 10);
+ } while (1);
+
+ remove_wait_queue(&vhost_vdpa.release_q, &wait);
+
+ mutex_lock(&vhost_vdpa.mutex);
+ device_destroy(vhost_vdpa.class,
+ MKDEV(MAJOR(vhost_vdpa.devt), v->minor));
+ vhost_vdpa_free_minor(v->minor);
+ mutex_unlock(&vhost_vdpa.mutex);
+ kfree(v->vqs);
+ kfree(v);
+}
+
+static struct vdpa_driver vhost_vdpa_driver = {
+ .drv = {
+ .name = "vhost_vdpa",
+ },
+ .probe = vhost_vdpa_probe,
+ .remove = vhost_vdpa_remove,
+};
+
+static char *vhost_vdpa_devnode(struct device *dev, umode_t *mode)
+{
+ return kasprintf(GFP_KERNEL, "vhost-vdpa/%s", dev_name(dev));
+}
+
+static int __init vhost_vdpa_init(void)
+{
+ int r;
+
+ idr_init(&vhost_vdpa.idr);
+ mutex_init(&vhost_vdpa.mutex);
+ init_waitqueue_head(&vhost_vdpa.release_q);
+
+ /* /dev/vhost-vdpa/$vdpa_device_index */
+ vhost_vdpa.class = class_create(THIS_MODULE, "vhost-vdpa");
+ if (IS_ERR(vhost_vdpa.class)) {
+ r = PTR_ERR(vhost_vdpa.class);
+ goto err_class;
+ }
+
+ vhost_vdpa.class->devnode = vhost_vdpa_devnode;
+
+ r = alloc_chrdev_region(&vhost_vdpa.devt, 0, MINORMASK + 1,
+ "vhost-vdpa");
+ if (r)
+ goto err_alloc_chrdev;
+
+ cdev_init(&vhost_vdpa.cdev, &vhost_vdpa_fops);
+ r = cdev_add(&vhost_vdpa.cdev, vhost_vdpa.devt, MINORMASK + 1);
+ if (r)
+ goto err_cdev_add;
+
+ r = register_vdpa_driver(&vhost_vdpa_driver);
+ if (r)
+ goto err_register_vdpa_driver;
+
+ return 0;
+
+err_register_vdpa_driver:
+ cdev_del(&vhost_vdpa.cdev);
+err_cdev_add:
+ unregister_chrdev_region(vhost_vdpa.devt, MINORMASK + 1);
+err_alloc_chrdev:
+ class_destroy(vhost_vdpa.class);
+err_class:
+ idr_destroy(&vhost_vdpa.idr);
+ return r;
+}
+module_init(vhost_vdpa_init);
+
+static void __exit vhost_vdpa_exit(void)
+{
+ unregister_vdpa_driver(&vhost_vdpa_driver);
+ cdev_del(&vhost_vdpa.cdev);
+ unregister_chrdev_region(vhost_vdpa.devt, MINORMASK + 1);
+ class_destroy(vhost_vdpa.class);
+ idr_destroy(&vhost_vdpa.idr);
+}
+module_exit(vhost_vdpa_exit);
+
+MODULE_VERSION("0.0.1");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("vDPA based vhost backend for virtio");
diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
index 40d028eed645..23f6db2106f5 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_VDPA specific defines */
+
+/* Get the device id. The device ids follow the same definition of
+ * the device id defined in virtio-spec. */
+#define VHOST_VDPA_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_VDPA_GET_STATUS _IOR(VHOST_VIRTIO, 0x71, __u8)
+#define VHOST_VDPA_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_VDPA_GET_CONFIG _IOR(VHOST_VIRTIO, 0x73, \
+ struct vhost_vdpa_config)
+#define VHOST_VDPA_SET_CONFIG _IOW(VHOST_VIRTIO, 0x74, \
+ struct vhost_vdpa_config)
+/* Enable/disable the ring. */
+#define VHOST_VDPA_SET_VRING_ENABLE _IOW(VHOST_VIRTIO, 0x75, \
+ struct vhost_vring_state)
+/* Get the max ring size. */
+#define VHOST_VDPA_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..669457ce5c48 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_VDPA specific definitions */
+
+struct vhost_vdpa_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
--
2.24.1