@@ -52,6 +52,17 @@ 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
+ select VDPA
+ 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_CROSS_ENDIAN_LEGACY
bool "Cross-endian support for vhost"
default n
@@ -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
new file mode 100644
@@ -0,0 +1,883 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018-2020 Intel Corporation.
+ * Copyright (C) 2020 Red Hat, Inc.
+ *
+ * Author: Tiwei Bie <tiwei.bie@intel.com>
+ * Jason Wang <jasowang@redhat.com>
+ *
+ * Thanks 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/iommu.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
+
+#define VHOST_VDPA_DEV_MAX (1U << MINORBITS)
+
+struct vhost_vdpa {
+ struct vhost_dev vdev;
+ struct iommu_domain *domain;
+ struct vhost_virtqueue *vqs;
+ struct completion completion;
+ struct vdpa_device *vdpa;
+ struct device dev;
+ struct cdev cdev;
+ atomic_t opened;
+ int nvqs;
+ int virtio_id;
+ int minor;
+};
+
+static DEFINE_IDA(vhost_vdpa_ida);
+
+static dev_t vhost_vdpa_major;
+
+static const u64 vhost_vdpa_features[] = {
+ [VIRTIO_ID_NET] = VHOST_VDPA_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_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);
+
+ 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;
+ }
+
+ 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)(uintptr_t)vq->desc,
+ (u64)(uintptr_t)vq->avail,
+ (u64)(uintptr_t)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_unlocked_ioctl(struct file *filep,
+ unsigned int cmd, unsigned long arg)
+{
+ struct vhost_vdpa *v = filep->private_data;
+ struct vhost_dev *d = &v->vdev;
+ void __user *argp = (void __user *)arg;
+ long r;
+
+ mutex_lock(&d->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:
+ r = vhost_dev_ioctl(&v->vdev, cmd, argp);
+ if (r == -ENOIOCTLCMD)
+ r = vhost_vdpa_vring_ioctl(v, cmd, argp);
+ break;
+ }
+
+ mutex_unlock(&d->mutex);
+ return r;
+}
+
+static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
+{
+ struct vhost_dev *dev = &v->vdev;
+ struct vhost_iotlb *iotlb = dev->iotlb;
+ struct vhost_iotlb_map *map;
+ struct page *page;
+ unsigned long pfn, pinned;
+
+ while ((map = vhost_iotlb_itree_first(iotlb, start, last)) != NULL) {
+ pinned = map->size >> PAGE_SHIFT;
+ for (pfn = map->addr >> PAGE_SHIFT;
+ pinned > 0; pfn++, pinned--) {
+ page = pfn_to_page(pfn);
+ if (map->perm & VHOST_ACCESS_WO)
+ set_page_dirty_lock(page);
+ unpin_user_page(page);
+ }
+ atomic64_sub(map->size >> PAGE_SHIFT, &dev->mm->pinned_vm);
+ vhost_iotlb_map_free(iotlb, map);
+ }
+}
+
+static void vhost_vdpa_iotlb_free(struct vhost_vdpa *v)
+{
+ struct vhost_dev *dev = &v->vdev;
+
+ vhost_vdpa_iotlb_unmap(v, 0ULL, 0ULL - 1);
+ kfree(dev->iotlb);
+ dev->iotlb = NULL;
+}
+
+static int perm_to_iommu_flags(u32 perm)
+{
+ int flags = 0;
+
+ switch (perm) {
+ case VHOST_ACCESS_WO:
+ flags |= IOMMU_WRITE;
+ break;
+ case VHOST_ACCESS_RO:
+ flags |= IOMMU_READ;
+ break;
+ case VHOST_ACCESS_RW:
+ flags |= (IOMMU_WRITE | IOMMU_READ);
+ break;
+ default:
+ WARN(1, "invalidate vhost IOTLB permission\n");
+ break;
+ }
+
+ return flags | IOMMU_CACHE;
+}
+
+static int vhost_vdpa_map(struct vhost_vdpa *v,
+ u64 iova, u64 size, u64 pa, u32 perm)
+{
+ struct vhost_dev *dev = &v->vdev;
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ int r = 0;
+
+ r = vhost_iotlb_add_range(dev->iotlb, iova, iova + size - 1,
+ pa, perm);
+ if (r)
+ return r;
+
+ if (ops->dma_map)
+ r = ops->dma_map(vdpa, iova, size, pa, perm);
+ else if (ops->set_map)
+ r = ops->set_map(vdpa, dev->iotlb);
+ else
+ r = iommu_map(v->domain, iova, pa, size,
+ perm_to_iommu_flags(perm));
+
+ return r;
+}
+
+static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size)
+{
+ struct vhost_dev *dev = &v->vdev;
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+
+ vhost_vdpa_iotlb_unmap(v, iova, iova + size - 1);
+
+ if (ops->dma_map)
+ ops->dma_unmap(vdpa, iova, size);
+ else if (ops->set_map)
+ ops->set_map(vdpa, dev->iotlb);
+ else
+ iommu_unmap(v->domain, iova, size);
+}
+
+static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
+ struct vhost_iotlb_msg *msg)
+{
+ struct vhost_dev *dev = &v->vdev;
+ struct vhost_iotlb *iotlb = dev->iotlb;
+ struct page **page_list;
+ unsigned long list_size = PAGE_SIZE / sizeof(struct page *);
+ unsigned int gup_flags = FOLL_LONGTERM;
+ unsigned long npages, cur_base, map_pfn, last_pfn = 0;
+ unsigned long locked, lock_limit, pinned, i;
+ u64 iova = msg->iova;
+ int ret = 0;
+
+ if (vhost_iotlb_itree_first(iotlb, msg->iova,
+ msg->iova + msg->size - 1))
+ return -EEXIST;
+
+ page_list = (struct page **) __get_free_page(GFP_KERNEL);
+ if (!page_list)
+ return -ENOMEM;
+
+ if (msg->perm & VHOST_ACCESS_WO)
+ gup_flags |= FOLL_WRITE;
+
+ npages = PAGE_ALIGN(msg->size + (iova & ~PAGE_MASK)) >> PAGE_SHIFT;
+ if (!npages)
+ return -EINVAL;
+
+ down_read(&dev->mm->mmap_sem);
+
+ locked = atomic64_add_return(npages, &dev->mm->pinned_vm);
+ lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+
+ if (locked > lock_limit) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ cur_base = msg->uaddr & PAGE_MASK;
+ iova &= PAGE_MASK;
+
+ while (npages) {
+ pinned = min_t(unsigned long, npages, list_size);
+ ret = pin_user_pages(cur_base, pinned,
+ gup_flags, page_list, NULL);
+ if (ret != pinned)
+ goto out;
+
+ if (!last_pfn)
+ map_pfn = page_to_pfn(page_list[0]);
+
+ for (i = 0; i < ret; i++) {
+ unsigned long this_pfn = page_to_pfn(page_list[i]);
+ u64 csize;
+
+ if (last_pfn && (this_pfn != last_pfn + 1)) {
+ /* Pin a contiguous chunk of memory */
+ csize = (last_pfn - map_pfn + 1) << PAGE_SHIFT;
+ if (vhost_vdpa_map(v, iova, csize,
+ map_pfn << PAGE_SHIFT,
+ msg->perm))
+ goto out;
+ map_pfn = this_pfn;
+ iova += csize;
+ }
+
+ last_pfn = this_pfn;
+ }
+
+ cur_base += ret << PAGE_SHIFT;
+ npages -= ret;
+ }
+
+ /* Pin the rest chunk */
+ ret = vhost_vdpa_map(v, iova, (last_pfn - map_pfn + 1) << PAGE_SHIFT,
+ map_pfn << PAGE_SHIFT, msg->perm);
+out:
+ if (ret) {
+ vhost_vdpa_unmap(v, msg->iova, msg->size);
+ atomic64_sub(npages, &dev->mm->pinned_vm);
+ }
+ up_read(&dev->mm->mmap_sem);
+ free_page((unsigned long)page_list);
+ return ret;
+}
+
+static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev,
+ struct vhost_iotlb_msg *msg)
+{
+ struct vhost_vdpa *v = container_of(dev, struct vhost_vdpa, vdev);
+ int r = 0;
+
+ r = vhost_dev_check_owner(dev);
+ if (r)
+ return r;
+
+ switch (msg->type) {
+ case VHOST_IOTLB_UPDATE:
+ r = vhost_vdpa_process_iotlb_update(v, msg);
+ break;
+ case VHOST_IOTLB_INVALIDATE:
+ vhost_vdpa_unmap(v, msg->iova, msg->size);
+ break;
+ default:
+ r = -EINVAL;
+ break;
+ }
+
+ return r;
+}
+
+static ssize_t vhost_vdpa_chr_write_iter(struct kiocb *iocb,
+ struct iov_iter *from)
+{
+ struct file *file = iocb->ki_filp;
+ struct vhost_vdpa *v = file->private_data;
+ struct vhost_dev *dev = &v->vdev;
+
+ return vhost_chr_write_iter(dev, from);
+}
+
+static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+ struct device *dma_dev = vdpa_get_dma_dev(vdpa);
+ struct bus_type *bus;
+ int ret;
+
+ /* Device want to do DMA by itself */
+ if (ops->set_map || ops->dma_map)
+ return 0;
+
+ bus = dma_dev->bus;
+ if (!bus)
+ return -EFAULT;
+
+ if (!iommu_capable(bus, IOMMU_CAP_CACHE_COHERENCY))
+ return -ENOTSUPP;
+
+ v->domain = iommu_domain_alloc(bus);
+ if (!v->domain)
+ return -EIO;
+
+ ret = iommu_attach_device(v->domain, dma_dev);
+ if (ret)
+ goto err_attach;
+
+ return 0;
+
+err_attach:
+ iommu_domain_free(v->domain);
+ return ret;
+}
+
+static void vhost_vdpa_free_domain(struct vhost_vdpa *v)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ struct device *dma_dev = vdpa_get_dma_dev(vdpa);
+
+ if (v->domain) {
+ iommu_detach_device(v->domain, dma_dev);
+ iommu_domain_free(v->domain);
+ }
+
+ v->domain = NULL;
+}
+
+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 = container_of(inode->i_cdev, struct vhost_vdpa, cdev);
+ if (!v)
+ return -ENODEV;
+
+ opened = atomic_cmpxchg(&v->opened, 0, 1);
+ if (opened)
+ return -EBUSY;
+
+ 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,
+ vhost_vdpa_process_iotlb_msg);
+
+ dev->iotlb = vhost_iotlb_alloc(0, 0);
+ if (!dev->iotlb) {
+ r = -ENOMEM;
+ goto err_init_iotlb;
+ }
+
+ r = vhost_vdpa_alloc_domain(v);
+ if (r)
+ goto err_init_iotlb;
+
+ filep->private_data = v;
+
+ return 0;
+
+err_init_iotlb:
+ vhost_dev_cleanup(&v->vdev);
+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;
+ struct vhost_dev *d = &v->vdev;
+
+ mutex_lock(&d->mutex);
+ filep->private_data = NULL;
+ vhost_vdpa_reset(v);
+ vhost_dev_stop(&v->vdev);
+ vhost_vdpa_iotlb_free(v);
+ vhost_vdpa_free_domain(v);
+ vhost_dev_cleanup(&v->vdev);
+ kfree(v->vdev.vqs);
+ mutex_unlock(&d->mutex);
+
+ atomic_dec(&v->opened);
+ complete(&v->completion);
+
+ return 0;
+}
+
+static const struct file_operations vhost_vdpa_fops = {
+ .owner = THIS_MODULE,
+ .open = vhost_vdpa_open,
+ .release = vhost_vdpa_release,
+ .write_iter = vhost_vdpa_chr_write_iter,
+ .unlocked_ioctl = vhost_vdpa_unlocked_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+};
+
+static void vhost_vdpa_release_dev(struct device *device)
+{
+ struct vhost_vdpa *v =
+ container_of(device, struct vhost_vdpa, dev);
+
+ ida_simple_remove(&vhost_vdpa_ida, v->minor);
+ kfree(v->vqs);
+ kfree(v);
+}
+
+static int vhost_vdpa_probe(struct vdpa_device *vdpa)
+{
+ const struct vdpa_config_ops *ops = vdpa->config;
+ struct vhost_vdpa *v;
+ int minor, nvqs = VHOST_VDPA_VQ_MAX;
+ int r;
+
+ /* Currently, we only accept the network devices. */
+ if (ops->get_device_id(vdpa) != VIRTIO_ID_NET)
+ return -ENOTSUPP;
+
+ v = kzalloc(sizeof(*v), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
+ if (!v)
+ return -ENOMEM;
+
+ minor = ida_simple_get(&vhost_vdpa_ida, 0,
+ VHOST_VDPA_DEV_MAX, GFP_KERNEL);
+ if (minor < 0) {
+ kfree(v);
+ return minor;
+ }
+
+ atomic_set(&v->opened, 0);
+ v->minor = minor;
+ v->vdpa = vdpa;
+ v->nvqs = nvqs;
+ v->virtio_id = ops->get_device_id(vdpa);
+
+ device_initialize(&v->dev);
+ v->dev.release = vhost_vdpa_release_dev;
+ v->dev.parent = &vdpa->dev;
+ v->dev.devt = MKDEV(MAJOR(vhost_vdpa_major), minor);
+ v->vqs = kmalloc_array(nvqs, sizeof(struct vhost_virtqueue),
+ GFP_KERNEL);
+ if (!v->vqs) {
+ r = -ENOMEM;
+ goto err;
+ }
+
+ r = dev_set_name(&v->dev, "vhost-vdpa-%u", minor);
+ if (r)
+ goto err;
+
+ cdev_init(&v->cdev, &vhost_vdpa_fops);
+ v->cdev.owner = THIS_MODULE;
+
+ r = cdev_device_add(&v->cdev, &v->dev);
+ if (r)
+ goto err;
+
+ init_completion(&v->completion);
+ vdpa_set_drvdata(vdpa, v);
+
+ return 0;
+
+err:
+ put_device(&v->dev);
+ return r;
+}
+
+static void vhost_vdpa_remove(struct vdpa_device *vdpa)
+{
+ struct vhost_vdpa *v = vdpa_get_drvdata(vdpa);
+ int opened;
+
+ cdev_device_del(&v->cdev, &v->dev);
+
+ do {
+ opened = atomic_cmpxchg(&v->opened, 0, 1);
+ if (!opened)
+ break;
+ wait_for_completion(&v->completion);
+ } while (1);
+
+ put_device(&v->dev);
+}
+
+static struct vdpa_driver vhost_vdpa_driver = {
+ .driver = {
+ .name = "vhost_vdpa",
+ },
+ .probe = vhost_vdpa_probe,
+ .remove = vhost_vdpa_remove,
+};
+
+static int __init vhost_vdpa_init(void)
+{
+ int r;
+
+ r = alloc_chrdev_region(&vhost_vdpa_major, 0, VHOST_VDPA_DEV_MAX,
+ "vhost-vdpa");
+ if (r)
+ goto err_alloc_chrdev;
+
+ r = vdpa_register_driver(&vhost_vdpa_driver);
+ if (r)
+ goto err_vdpa_register_driver;
+
+ return 0;
+
+err_vdpa_register_driver:
+ unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX);
+err_alloc_chrdev:
+ return r;
+}
+module_init(vhost_vdpa_init);
+
+static void __exit vhost_vdpa_exit(void)
+{
+ vdpa_unregister_driver(&vhost_vdpa_driver);
+ unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX);
+}
+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");
@@ -116,4 +116,28 @@
#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
@@ -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