diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
index 1409e40e6345ca8a7901e5e7b8963109a8c69099..293ca3aef3583cb845bee3ce9b3d961164ccdf69 100644
--- a/Documentation/userspace-api/ioctl/ioctl-number.rst
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
@@ -300,6 +300,7 @@ Code Seq# Include File Comments
'z' 10-4F drivers/s390/crypto/zcrypt_api.h conflict!
'|' 00-7F linux/media.h
0x80 00-1F linux/fb.h
+0x81 00-1F linux/vduse.h
0x89 00-06 arch/x86/include/asm/sockios.h
0x89 0B-DF linux/sockios.h
0x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range
diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
index e48e2b10ca36557bc91b4a925bddb9ea835f56e6..3d91982d837176fabe46ed237c7dd805094ac619 100644
--- a/drivers/vdpa/Kconfig
+++ b/drivers/vdpa/Kconfig
@@ -33,6 +33,16 @@ config VDPA_SIM_BLOCK
vDPA block device simulator which terminates IO request in a
memory buffer.
+config VDPA_USER
+ tristate "VDUSE (vDPA Device in Userspace) support"
+ depends on EVENTFD && MMU && HAS_DMA
+ select DMA_OPS
+ select VHOST_IOTLB
+ select IOMMU_IOVA
+ help
+ With VDUSE it is possible to emulate a vDPA Device
+ in a userspace program.
+
config IFCVF
tristate "Intel IFC VF vDPA driver"
depends on PCI_MSI
diff --git a/drivers/vdpa/Makefile b/drivers/vdpa/Makefile
index 67fe7f3d69437f7cadb860e571a9e12912c4aa35..f02ebed33f193eefcfaf187863b2a9ee05739067 100644
--- a/drivers/vdpa/Makefile
+++ b/drivers/vdpa/Makefile
@@ -1,6 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_VDPA) += vdpa.o
obj-$(CONFIG_VDPA_SIM) += vdpa_sim/
+obj-$(CONFIG_VDPA_USER) += vdpa_user/
obj-$(CONFIG_IFCVF) += ifcvf/
obj-$(CONFIG_MLX5_VDPA) += mlx5/
obj-$(CONFIG_VP_VDPA) += virtio_pci/
diff --git a/drivers/vdpa/vdpa_user/Makefile b/drivers/vdpa/vdpa_user/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..260e0b26af99e7d4c06a3d4220f1da265414c477
--- /dev/null
+++ b/drivers/vdpa/vdpa_user/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+
+vduse-y := vduse_dev.o iova_domain.o
+
+obj-$(CONFIG_VDPA_USER) += vduse.o
diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
new file mode 100644
index 0000000000000000000000000000000000000000..b9b2659408e6f6798f216a6893173823df714487
--- /dev/null
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c
@@ -0,0 +1,1646 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * VDUSE: vDPA Device in Userspace
+ *
+ * Copyright (C) 2020-2021 Bytedance Inc. and/or its affiliates. All rights reserved.
+ *
+ * Author: Xie Yongji <xieyongji@bytedance.com>
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/eventfd.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/dma-map-ops.h>
+#include <linux/poll.h>
+#include <linux/file.h>
+#include <linux/uio.h>
+#include <linux/vdpa.h>
+#include <linux/nospec.h>
+#include <uapi/linux/vduse.h>
+#include <uapi/linux/vdpa.h>
+#include <uapi/linux/virtio_config.h>
+#include <uapi/linux/virtio_ids.h>
+#include <uapi/linux/virtio_blk.h>
+#include <linux/mod_devicetable.h>
+
+#include "iova_domain.h"
+
+#define DRV_AUTHOR "Yongji Xie <xieyongji@bytedance.com>"
+#define DRV_DESC "vDPA Device in Userspace"
+#define DRV_LICENSE "GPL v2"
+
+#define VDUSE_DEV_MAX (1U << MINORBITS)
+#define VDUSE_BOUNCE_SIZE (64 * 1024 * 1024)
+#define VDUSE_IOVA_SIZE (128 * 1024 * 1024)
+#define VDUSE_MSG_DEFAULT_TIMEOUT 30
+
+struct vduse_virtqueue {
+ u16 index;
+ u16 num_max;
+ u32 num;
+ u64 desc_addr;
+ u64 driver_addr;
+ u64 device_addr;
+ struct vdpa_vq_state state;
+ bool ready;
+ bool kicked;
+ spinlock_t kick_lock;
+ spinlock_t irq_lock;
+ struct eventfd_ctx *kickfd;
+ struct vdpa_callback cb;
+ struct work_struct inject;
+ struct work_struct kick;
+};
+
+struct vduse_dev;
+
+struct vduse_vdpa {
+ struct vdpa_device vdpa;
+ struct vduse_dev *dev;
+};
+
+struct vduse_dev {
+ struct vduse_vdpa *vdev;
+ struct device *dev;
+ struct vduse_virtqueue *vqs;
+ struct vduse_iova_domain *domain;
+ char *name;
+ struct mutex lock;
+ spinlock_t msg_lock;
+ u64 msg_unique;
+ u32 msg_timeout;
+ wait_queue_head_t waitq;
+ struct list_head send_list;
+ struct list_head recv_list;
+ struct vdpa_callback config_cb;
+ struct work_struct inject;
+ spinlock_t irq_lock;
+ int minor;
+ bool broken;
+ bool connected;
+ u64 api_version;
+ u64 device_features;
+ u64 driver_features;
+ u32 device_id;
+ u32 vendor_id;
+ u32 generation;
+ u32 config_size;
+ void *config;
+ u8 status;
+ u32 vq_num;
+ u32 vq_align;
+};
+
+struct vduse_dev_msg {
+ struct vduse_dev_request req;
+ struct vduse_dev_response resp;
+ struct list_head list;
+ wait_queue_head_t waitq;
+ bool completed;
+};
+
+struct vduse_control {
+ u64 api_version;
+};
+
+static DEFINE_MUTEX(vduse_lock);
+static DEFINE_IDR(vduse_idr);
+
+static dev_t vduse_major;
+static struct class *vduse_class;
+static struct cdev vduse_ctrl_cdev;
+static struct cdev vduse_cdev;
+static struct workqueue_struct *vduse_irq_wq;
+
+static u32 allowed_device_id[] = {
+ VIRTIO_ID_BLOCK,
+};
+
+static inline struct vduse_dev *vdpa_to_vduse(struct vdpa_device *vdpa)
+{
+ struct vduse_vdpa *vdev = container_of(vdpa, struct vduse_vdpa, vdpa);
+
+ return vdev->dev;
+}
+
+static inline struct vduse_dev *dev_to_vduse(struct device *dev)
+{
+ struct vdpa_device *vdpa = dev_to_vdpa(dev);
+
+ return vdpa_to_vduse(vdpa);
+}
+
+static struct vduse_dev_msg *vduse_find_msg(struct list_head *head,
+ uint32_t request_id)
+{
+ struct vduse_dev_msg *msg;
+
+ list_for_each_entry(msg, head, list) {
+ if (msg->req.request_id == request_id) {
+ list_del(&msg->list);
+ return msg;
+ }
+ }
+
+ return NULL;
+}
+
+static struct vduse_dev_msg *vduse_dequeue_msg(struct list_head *head)
+{
+ struct vduse_dev_msg *msg = NULL;
+
+ if (!list_empty(head)) {
+ msg = list_first_entry(head, struct vduse_dev_msg, list);
+ list_del(&msg->list);
+ }
+
+ return msg;
+}
+
+static void vduse_enqueue_msg(struct list_head *head,
+ struct vduse_dev_msg *msg)
+{
+ list_add_tail(&msg->list, head);
+}
+
+static void vduse_dev_broken(struct vduse_dev *dev)
+{
+ struct vduse_dev_msg *msg, *tmp;
+
+ if (unlikely(dev->broken))
+ return;
+
+ list_splice_init(&dev->recv_list, &dev->send_list);
+ list_for_each_entry_safe(msg, tmp, &dev->send_list, list) {
+ list_del(&msg->list);
+ msg->completed = 1;
+ msg->resp.result = VDUSE_REQ_RESULT_FAILED;
+ wake_up(&msg->waitq);
+ }
+ dev->broken = true;
+ wake_up(&dev->waitq);
+}
+
+static int vduse_dev_msg_sync(struct vduse_dev *dev,
+ struct vduse_dev_msg *msg)
+{
+ int ret;
+
+ if (unlikely(dev->broken))
+ return -EIO;
+
+ init_waitqueue_head(&msg->waitq);
+ spin_lock(&dev->msg_lock);
+ if (unlikely(dev->broken)) {
+ spin_unlock(&dev->msg_lock);
+ return -EIO;
+ }
+ msg->req.request_id = dev->msg_unique++;
+ vduse_enqueue_msg(&dev->send_list, msg);
+ wake_up(&dev->waitq);
+ spin_unlock(&dev->msg_lock);
+ if (dev->msg_timeout)
+ ret = wait_event_killable_timeout(msg->waitq, msg->completed,
+ (long)dev->msg_timeout * HZ);
+ else
+ ret = wait_event_killable(msg->waitq, msg->completed);
+
+ spin_lock(&dev->msg_lock);
+ if (!msg->completed) {
+ list_del(&msg->list);
+ msg->resp.result = VDUSE_REQ_RESULT_FAILED;
+ /* Mark the device as malfunction when there is a timeout */
+ if (!ret)
+ vduse_dev_broken(dev);
+ }
+ ret = (msg->resp.result == VDUSE_REQ_RESULT_OK) ? 0 : -EIO;
+ spin_unlock(&dev->msg_lock);
+
+ return ret;
+}
+
+static int vduse_dev_get_vq_state_packed(struct vduse_dev *dev,
+ struct vduse_virtqueue *vq,
+ struct vdpa_vq_state_packed *packed)
+{
+ struct vduse_dev_msg msg = { 0 };
+ int ret;
+
+ msg.req.type = VDUSE_GET_VQ_STATE;
+ msg.req.vq_state.index = vq->index;
+
+ ret = vduse_dev_msg_sync(dev, &msg);
+ if (ret)
+ return ret;
+
+ packed->last_avail_counter =
+ msg.resp.vq_state.packed.last_avail_counter & 0x0001;
+ packed->last_avail_idx =
+ msg.resp.vq_state.packed.last_avail_idx & 0x7FFF;
+ packed->last_used_counter =
+ msg.resp.vq_state.packed.last_used_counter & 0x0001;
+ packed->last_used_idx =
+ msg.resp.vq_state.packed.last_used_idx & 0x7FFF;
+
+ return 0;
+}
+
+static int vduse_dev_get_vq_state_split(struct vduse_dev *dev,
+ struct vduse_virtqueue *vq,
+ struct vdpa_vq_state_split *split)
+{
+ struct vduse_dev_msg msg = { 0 };
+ int ret;
+
+ msg.req.type = VDUSE_GET_VQ_STATE;
+ msg.req.vq_state.index = vq->index;
+
+ ret = vduse_dev_msg_sync(dev, &msg);
+ if (ret)
+ return ret;
+
+ split->avail_index = msg.resp.vq_state.split.avail_index;
+
+ return 0;
+}
+
+static int vduse_dev_set_status(struct vduse_dev *dev, u8 status)
+{
+ struct vduse_dev_msg msg = { 0 };
+
+ msg.req.type = VDUSE_SET_STATUS;
+ msg.req.s.status = status;
+
+ return vduse_dev_msg_sync(dev, &msg);
+}
+
+static int vduse_dev_update_iotlb(struct vduse_dev *dev,
+ u64 start, u64 last)
+{
+ struct vduse_dev_msg msg = { 0 };
+
+ if (last < start)
+ return -EINVAL;
+
+ msg.req.type = VDUSE_UPDATE_IOTLB;
+ msg.req.iova.start = start;
+ msg.req.iova.last = last;
+
+ return vduse_dev_msg_sync(dev, &msg);
+}
+
+static ssize_t vduse_dev_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+ struct file *file = iocb->ki_filp;
+ struct vduse_dev *dev = file->private_data;
+ struct vduse_dev_msg *msg;
+ int size = sizeof(struct vduse_dev_request);
+ ssize_t ret;
+
+ if (iov_iter_count(to) < size)
+ return -EINVAL;
+
+ spin_lock(&dev->msg_lock);
+ while (1) {
+ msg = vduse_dequeue_msg(&dev->send_list);
+ if (msg)
+ break;
+
+ ret = -EAGAIN;
+ if (file->f_flags & O_NONBLOCK)
+ goto unlock;
+
+ spin_unlock(&dev->msg_lock);
+ ret = wait_event_interruptible_exclusive(dev->waitq,
+ !list_empty(&dev->send_list));
+ if (ret)
+ return ret;
+
+ spin_lock(&dev->msg_lock);
+ }
+ spin_unlock(&dev->msg_lock);
+ ret = copy_to_iter(&msg->req, size, to);
+ spin_lock(&dev->msg_lock);
+ if (ret != size) {
+ ret = -EFAULT;
+ vduse_enqueue_msg(&dev->send_list, msg);
+ goto unlock;
+ }
+ vduse_enqueue_msg(&dev->recv_list, msg);
+unlock:
+ spin_unlock(&dev->msg_lock);
+
+ return ret;
+}
+
+static bool is_mem_zero(const char *ptr, int size)
+{
+ int i;
+
+ for (i = 0; i < size; i++) {
+ if (ptr[i])
+ return false;
+ }
+ return true;
+}
+
+static ssize_t vduse_dev_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+ struct file *file = iocb->ki_filp;
+ struct vduse_dev *dev = file->private_data;
+ struct vduse_dev_response resp;
+ struct vduse_dev_msg *msg;
+ size_t ret;
+
+ ret = copy_from_iter(&resp, sizeof(resp), from);
+ if (ret != sizeof(resp))
+ return -EINVAL;
+
+ if (!is_mem_zero((const char *)resp.reserved, sizeof(resp.reserved)))
+ return -EINVAL;
+
+ spin_lock(&dev->msg_lock);
+ msg = vduse_find_msg(&dev->recv_list, resp.request_id);
+ if (!msg) {
+ ret = -ENOENT;
+ goto unlock;
+ }
+
+ memcpy(&msg->resp, &resp, sizeof(resp));
+ msg->completed = 1;
+ wake_up(&msg->waitq);
+unlock:
+ spin_unlock(&dev->msg_lock);
+
+ return ret;
+}
+
+static __poll_t vduse_dev_poll(struct file *file, poll_table *wait)
+{
+ struct vduse_dev *dev = file->private_data;
+ __poll_t mask = 0;
+
+ poll_wait(file, &dev->waitq, wait);
+
+ spin_lock(&dev->msg_lock);
+
+ if (unlikely(dev->broken))
+ mask |= EPOLLERR;
+ if (!list_empty(&dev->send_list))
+ mask |= EPOLLIN | EPOLLRDNORM;
+ if (!list_empty(&dev->recv_list))
+ mask |= EPOLLOUT | EPOLLWRNORM;
+
+ spin_unlock(&dev->msg_lock);
+
+ return mask;
+}
+
+static void vduse_dev_reset(struct vduse_dev *dev)
+{
+ int i;
+ struct vduse_iova_domain *domain = dev->domain;
+
+ /* The coherent mappings are handled in vduse_dev_free_coherent() */
+ if (domain->bounce_map)
+ vduse_domain_reset_bounce_map(domain);
+
+ dev->status = 0;
+ dev->driver_features = 0;
+ dev->generation++;
+ spin_lock(&dev->irq_lock);
+ dev->config_cb.callback = NULL;
+ dev->config_cb.private = NULL;
+ spin_unlock(&dev->irq_lock);
+ flush_work(&dev->inject);
+
+ for (i = 0; i < dev->vq_num; i++) {
+ struct vduse_virtqueue *vq = &dev->vqs[i];
+
+ vq->ready = false;
+ vq->desc_addr = 0;
+ vq->driver_addr = 0;
+ vq->device_addr = 0;
+ vq->num = 0;
+ memset(&vq->state, 0, sizeof(vq->state));
+
+ spin_lock(&vq->kick_lock);
+ vq->kicked = false;
+ if (vq->kickfd)
+ eventfd_ctx_put(vq->kickfd);
+ vq->kickfd = NULL;
+ spin_unlock(&vq->kick_lock);
+
+ spin_lock(&vq->irq_lock);
+ vq->cb.callback = NULL;
+ vq->cb.private = NULL;
+ spin_unlock(&vq->irq_lock);
+ flush_work(&vq->inject);
+ flush_work(&vq->kick);
+ }
+}
+
+static int vduse_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 idx,
+ u64 desc_area, u64 driver_area,
+ u64 device_area)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+ struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+ vq->desc_addr = desc_area;
+ vq->driver_addr = driver_area;
+ vq->device_addr = device_area;
+
+ return 0;
+}
+
+static void vduse_vq_kick(struct vduse_virtqueue *vq)
+{
+ spin_lock(&vq->kick_lock);
+ if (!vq->ready)
+ goto unlock;
+
+ if (vq->kickfd)
+ eventfd_signal(vq->kickfd, 1);
+ else
+ vq->kicked = true;
+unlock:
+ spin_unlock(&vq->kick_lock);
+}
+
+static void vduse_vq_kick_work(struct work_struct *work)
+{
+ struct vduse_virtqueue *vq = container_of(work,
+ struct vduse_virtqueue, kick);
+
+ vduse_vq_kick(vq);
+}
+
+static void vduse_vdpa_kick_vq(struct vdpa_device *vdpa, u16 idx)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+ struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+ /*
+ * TODO: after applying b542e383d8c0 ("eventfd: Make signal recursion protection a task bit")
+ * replace eventfd_signal_count with eventfd_signal_allowed, and
+ * drop the previous ("eventfd: Export eventfd_wake_count to modules")
+ * */
+ if (eventfd_signal_count()) {
+ schedule_work(&vq->kick);
+ return;
+ }
+ vduse_vq_kick(vq);
+}
+
+static void vduse_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 idx,
+ struct vdpa_callback *cb)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+ struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+ spin_lock(&vq->irq_lock);
+ vq->cb.callback = cb->callback;
+ vq->cb.private = cb->private;
+ spin_unlock(&vq->irq_lock);
+}
+
+static void vduse_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 idx, u32 num)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+ struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+ vq->num = num;
+}
+
+static void vduse_vdpa_set_vq_ready(struct vdpa_device *vdpa,
+ u16 idx, bool ready)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+ struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+ vq->ready = ready;
+}
+
+static bool vduse_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 idx)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+ struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+ return vq->ready;
+}
+
+static int vduse_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 idx,
+ const struct vdpa_vq_state *state)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+ struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+ if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED)) {
+ vq->state.packed.last_avail_counter =
+ state->packed.last_avail_counter;
+ vq->state.packed.last_avail_idx = state->packed.last_avail_idx;
+ vq->state.packed.last_used_counter =
+ state->packed.last_used_counter;
+ vq->state.packed.last_used_idx = state->packed.last_used_idx;
+ } else
+ vq->state.split.avail_index = state->split.avail_index;
+
+ return 0;
+}
+
+static int vduse_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 idx,
+ struct vdpa_vq_state *state)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+ struct vduse_virtqueue *vq = &dev->vqs[idx];
+
+ if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED))
+ return vduse_dev_get_vq_state_packed(dev, vq, &state->packed);
+
+ return vduse_dev_get_vq_state_split(dev, vq, &state->split);
+}
+
+static u32 vduse_vdpa_get_vq_align(struct vdpa_device *vdpa)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ return dev->vq_align;
+}
+
+static u64 vduse_vdpa_get_features(struct vdpa_device *vdpa)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ return dev->device_features;
+}
+
+static int vduse_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ dev->driver_features = features;
+ return 0;
+}
+
+static void vduse_vdpa_set_config_cb(struct vdpa_device *vdpa,
+ struct vdpa_callback *cb)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ spin_lock(&dev->irq_lock);
+ dev->config_cb.callback = cb->callback;
+ dev->config_cb.private = cb->private;
+ spin_unlock(&dev->irq_lock);
+}
+
+static u16 vduse_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+ u16 num_max = 0;
+ int i;
+
+ for (i = 0; i < dev->vq_num; i++)
+ if (num_max < dev->vqs[i].num_max)
+ num_max = dev->vqs[i].num_max;
+
+ return num_max;
+}
+
+static u32 vduse_vdpa_get_device_id(struct vdpa_device *vdpa)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ return dev->device_id;
+}
+
+static u32 vduse_vdpa_get_vendor_id(struct vdpa_device *vdpa)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ return dev->vendor_id;
+}
+
+static u8 vduse_vdpa_get_status(struct vdpa_device *vdpa)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ return dev->status;
+}
+
+static void vduse_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ if (vduse_dev_set_status(dev, status))
+ return;
+
+ dev->status = status;
+}
+
+static size_t vduse_vdpa_get_config_size(struct vdpa_device *vdpa)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ return dev->config_size;
+}
+
+static void vduse_vdpa_get_config(struct vdpa_device *vdpa, unsigned int offset,
+ void *buf, unsigned int len)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ if (len > dev->config_size - offset)
+ return;
+
+ memcpy(buf, dev->config + offset, len);
+}
+
+static void vduse_vdpa_set_config(struct vdpa_device *vdpa, unsigned int offset,
+ const void *buf, unsigned int len)
+{
+ /* Now we only support read-only configuration space */
+}
+
+static int vduse_vdpa_reset(struct vdpa_device *vdpa)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ if (vduse_dev_set_status(dev, 0))
+ return -EIO;
+
+ vduse_dev_reset(dev);
+
+ return 0;
+}
+
+static u32 vduse_vdpa_get_generation(struct vdpa_device *vdpa)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ return dev->generation;
+}
+
+static int vduse_vdpa_set_map(struct vdpa_device *vdpa,
+ struct vhost_iotlb *iotlb)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+ int ret;
+
+ ret = vduse_domain_set_map(dev->domain, iotlb);
+ if (ret)
+ return ret;
+
+ ret = vduse_dev_update_iotlb(dev, 0ULL, ULLONG_MAX);
+ if (ret) {
+ vduse_domain_clear_map(dev->domain, iotlb);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void vduse_vdpa_free(struct vdpa_device *vdpa)
+{
+ struct vduse_dev *dev = vdpa_to_vduse(vdpa);
+
+ dev->vdev = NULL;
+}
+
+static const struct vdpa_config_ops vduse_vdpa_config_ops = {
+ .set_vq_address = vduse_vdpa_set_vq_address,
+ .kick_vq = vduse_vdpa_kick_vq,
+ .set_vq_cb = vduse_vdpa_set_vq_cb,
+ .set_vq_num = vduse_vdpa_set_vq_num,
+ .set_vq_ready = vduse_vdpa_set_vq_ready,
+ .get_vq_ready = vduse_vdpa_get_vq_ready,
+ .set_vq_state = vduse_vdpa_set_vq_state,
+ .get_vq_state = vduse_vdpa_get_vq_state,
+ .get_vq_align = vduse_vdpa_get_vq_align,
+ .get_features = vduse_vdpa_get_features,
+ .set_features = vduse_vdpa_set_features,
+ .set_config_cb = vduse_vdpa_set_config_cb,
+ .get_vq_num_max = vduse_vdpa_get_vq_num_max,
+ .get_device_id = vduse_vdpa_get_device_id,
+ .get_vendor_id = vduse_vdpa_get_vendor_id,
+ .get_status = vduse_vdpa_get_status,
+ .set_status = vduse_vdpa_set_status,
+ .get_config_size = vduse_vdpa_get_config_size,
+ .get_config = vduse_vdpa_get_config,
+ .set_config = vduse_vdpa_set_config,
+ .get_generation = vduse_vdpa_get_generation,
+ .reset = vduse_vdpa_reset,
+ .set_map = vduse_vdpa_set_map,
+ .free = vduse_vdpa_free,
+};
+
+static dma_addr_t vduse_dev_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ struct vduse_dev *vdev = dev_to_vduse(dev);
+ struct vduse_iova_domain *domain = vdev->domain;
+
+ return vduse_domain_map_page(domain, page, offset, size, dir, attrs);
+}
+
+static void vduse_dev_unmap_page(struct device *dev, dma_addr_t dma_addr,
+ size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ struct vduse_dev *vdev = dev_to_vduse(dev);
+ struct vduse_iova_domain *domain = vdev->domain;
+
+ return vduse_domain_unmap_page(domain, dma_addr, size, dir, attrs);
+}
+
+static void *vduse_dev_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t *dma_addr, gfp_t flag,
+ unsigned long attrs)
+{
+ struct vduse_dev *vdev = dev_to_vduse(dev);
+ struct vduse_iova_domain *domain = vdev->domain;
+ unsigned long iova;
+ void *addr;
+
+ *dma_addr = DMA_MAPPING_ERROR;
+ addr = vduse_domain_alloc_coherent(domain, size,
+ (dma_addr_t *)&iova, flag, attrs);
+ if (!addr)
+ return NULL;
+
+ *dma_addr = (dma_addr_t)iova;
+
+ return addr;
+}
+
+static void vduse_dev_free_coherent(struct device *dev, size_t size,
+ void *vaddr, dma_addr_t dma_addr,
+ unsigned long attrs)
+{
+ struct vduse_dev *vdev = dev_to_vduse(dev);
+ struct vduse_iova_domain *domain = vdev->domain;
+
+ vduse_domain_free_coherent(domain, size, vaddr, dma_addr, attrs);
+}
+
+static size_t vduse_dev_max_mapping_size(struct device *dev)
+{
+ struct vduse_dev *vdev = dev_to_vduse(dev);
+ struct vduse_iova_domain *domain = vdev->domain;
+
+ return domain->bounce_size;
+}
+
+static const struct dma_map_ops vduse_dev_dma_ops = {
+ .map_page = vduse_dev_map_page,
+ .unmap_page = vduse_dev_unmap_page,
+ .alloc = vduse_dev_alloc_coherent,
+ .free = vduse_dev_free_coherent,
+ .max_mapping_size = vduse_dev_max_mapping_size,
+};
+
+static unsigned int perm_to_file_flags(u8 perm)
+{
+ unsigned int flags = 0;
+
+ switch (perm) {
+ case VDUSE_ACCESS_WO:
+ flags |= O_WRONLY;
+ break;
+ case VDUSE_ACCESS_RO:
+ flags |= O_RDONLY;
+ break;
+ case VDUSE_ACCESS_RW:
+ flags |= O_RDWR;
+ break;
+ default:
+ WARN(1, "invalidate vhost IOTLB permission\n");
+ break;
+ }
+
+ return flags;
+}
+
+static int vduse_kickfd_setup(struct vduse_dev *dev,
+ struct vduse_vq_eventfd *eventfd)
+{
+ struct eventfd_ctx *ctx = NULL;
+ struct vduse_virtqueue *vq;
+ u32 index;
+
+ if (eventfd->index >= dev->vq_num)
+ return -EINVAL;
+
+ index = array_index_nospec(eventfd->index, dev->vq_num);
+ vq = &dev->vqs[index];
+ if (eventfd->fd >= 0) {
+ ctx = eventfd_ctx_fdget(eventfd->fd);
+ if (IS_ERR(ctx))
+ return PTR_ERR(ctx);
+ } else if (eventfd->fd != VDUSE_EVENTFD_DEASSIGN)
+ return 0;
+
+ spin_lock(&vq->kick_lock);
+ if (vq->kickfd)
+ eventfd_ctx_put(vq->kickfd);
+ vq->kickfd = ctx;
+ if (vq->ready && vq->kicked && vq->kickfd) {
+ eventfd_signal(vq->kickfd, 1);
+ vq->kicked = false;
+ }
+ spin_unlock(&vq->kick_lock);
+
+ return 0;
+}
+
+static bool vduse_dev_is_ready(struct vduse_dev *dev)
+{
+ int i;
+
+ for (i = 0; i < dev->vq_num; i++)
+ if (!dev->vqs[i].num_max)
+ return false;
+
+ return true;
+}
+
+static void vduse_dev_irq_inject(struct work_struct *work)
+{
+ struct vduse_dev *dev = container_of(work, struct vduse_dev, inject);
+
+ spin_lock_irq(&dev->irq_lock);
+ if (dev->config_cb.callback)
+ dev->config_cb.callback(dev->config_cb.private);
+ spin_unlock_irq(&dev->irq_lock);
+}
+
+static void vduse_vq_irq_inject(struct work_struct *work)
+{
+ struct vduse_virtqueue *vq = container_of(work,
+ struct vduse_virtqueue, inject);
+
+ spin_lock_irq(&vq->irq_lock);
+ if (vq->ready && vq->cb.callback)
+ vq->cb.callback(vq->cb.private);
+ spin_unlock_irq(&vq->irq_lock);
+}
+
+static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct vduse_dev *dev = file->private_data;
+ void __user *argp = (void __user *)arg;
+ int ret;
+
+ if (unlikely(dev->broken))
+ return -EPERM;
+
+ switch (cmd) {
+ case VDUSE_IOTLB_GET_FD: {
+ struct vduse_iotlb_entry entry;
+ struct vhost_iotlb_map *map;
+ struct vdpa_map_file *map_file;
+ struct vduse_iova_domain *domain = dev->domain;
+ struct file *f = NULL;
+
+ ret = -EFAULT;
+ if (copy_from_user(&entry, argp, sizeof(entry)))
+ break;
+
+ ret = -EINVAL;
+ if (entry.start > entry.last)
+ break;
+
+ spin_lock(&domain->iotlb_lock);
+ map = vhost_iotlb_itree_first(domain->iotlb,
+ entry.start, entry.last);
+ if (map) {
+ map_file = (struct vdpa_map_file *)map->opaque;
+ f = get_file(map_file->file);
+ entry.offset = map_file->offset;
+ entry.start = map->start;
+ entry.last = map->last;
+ entry.perm = map->perm;
+ }
+ spin_unlock(&domain->iotlb_lock);
+ ret = -EINVAL;
+ if (!f)
+ break;
+
+ ret = -EFAULT;
+ if (copy_to_user(argp, &entry, sizeof(entry))) {
+ fput(f);
+ break;
+ }
+ ret = receive_fd(f, perm_to_file_flags(entry.perm));
+ fput(f);
+ break;
+ }
+ case VDUSE_DEV_GET_FEATURES:
+ /*
+ * Just mirror what driver wrote here.
+ * The driver is expected to check FEATURE_OK later.
+ */
+ ret = put_user(dev->driver_features, (u64 __user *)argp);
+ break;
+ case VDUSE_DEV_SET_CONFIG: {
+ struct vduse_config_data config;
+ unsigned long size = offsetof(struct vduse_config_data,
+ buffer);
+
+ ret = -EFAULT;
+ if (copy_from_user(&config, argp, size))
+ break;
+
+ ret = -EINVAL;
+ if (config.length == 0 ||
+ config.length > dev->config_size - config.offset)
+ break;
+
+ ret = -EFAULT;
+ if (copy_from_user(dev->config + config.offset, argp + size,
+ config.length))
+ break;
+
+ ret = 0;
+ break;
+ }
+ case VDUSE_DEV_INJECT_CONFIG_IRQ:
+ ret = 0;
+ queue_work(vduse_irq_wq, &dev->inject);
+ break;
+ case VDUSE_VQ_SETUP: {
+ struct vduse_vq_config config;
+ u32 index;
+
+ ret = -EFAULT;
+ if (copy_from_user(&config, argp, sizeof(config)))
+ break;
+
+ ret = -EINVAL;
+ if (config.index >= dev->vq_num)
+ break;
+
+ if (!is_mem_zero((const char *)config.reserved,
+ sizeof(config.reserved)))
+ break;
+
+ index = array_index_nospec(config.index, dev->vq_num);
+ dev->vqs[index].num_max = config.max_size;
+ ret = 0;
+ break;
+ }
+ case VDUSE_VQ_GET_INFO: {
+ struct vduse_vq_info vq_info;
+ struct vduse_virtqueue *vq;
+ u32 index;
+
+ ret = -EFAULT;
+ if (copy_from_user(&vq_info, argp, sizeof(vq_info)))
+ break;
+
+ ret = -EINVAL;
+ if (vq_info.index >= dev->vq_num)
+ break;
+
+ index = array_index_nospec(vq_info.index, dev->vq_num);
+ vq = &dev->vqs[index];
+ vq_info.desc_addr = vq->desc_addr;
+ vq_info.driver_addr = vq->driver_addr;
+ vq_info.device_addr = vq->device_addr;
+ vq_info.num = vq->num;
+
+ if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED)) {
+ vq_info.packed.last_avail_counter =
+ vq->state.packed.last_avail_counter;
+ vq_info.packed.last_avail_idx =
+ vq->state.packed.last_avail_idx;
+ vq_info.packed.last_used_counter =
+ vq->state.packed.last_used_counter;
+ vq_info.packed.last_used_idx =
+ vq->state.packed.last_used_idx;
+ } else
+ vq_info.split.avail_index =
+ vq->state.split.avail_index;
+
+ vq_info.ready = vq->ready;
+
+ ret = -EFAULT;
+ if (copy_to_user(argp, &vq_info, sizeof(vq_info)))
+ break;
+
+ ret = 0;
+ break;
+ }
+ case VDUSE_VQ_SETUP_KICKFD: {
+ struct vduse_vq_eventfd eventfd;
+
+ ret = -EFAULT;
+ if (copy_from_user(&eventfd, argp, sizeof(eventfd)))
+ break;
+
+ ret = vduse_kickfd_setup(dev, &eventfd);
+ break;
+ }
+ case VDUSE_VQ_INJECT_IRQ: {
+ u32 index;
+
+ ret = -EFAULT;
+ if (get_user(index, (u32 __user *)argp))
+ break;
+
+ ret = -EINVAL;
+ if (index >= dev->vq_num)
+ break;
+
+ ret = 0;
+ index = array_index_nospec(index, dev->vq_num);
+ queue_work(vduse_irq_wq, &dev->vqs[index].inject);
+ break;
+ }
+ default:
+ ret = -ENOIOCTLCMD;
+ break;
+ }
+
+ return ret;
+}
+
+static int vduse_dev_release(struct inode *inode, struct file *file)
+{
+ struct vduse_dev *dev = file->private_data;
+
+ spin_lock(&dev->msg_lock);
+ /* Make sure the inflight messages can processed after reconncection */
+ list_splice_init(&dev->recv_list, &dev->send_list);
+ spin_unlock(&dev->msg_lock);
+ dev->connected = false;
+
+ return 0;
+}
+
+static struct vduse_dev *vduse_dev_get_from_minor(int minor)
+{
+ struct vduse_dev *dev;
+
+ mutex_lock(&vduse_lock);
+ dev = idr_find(&vduse_idr, minor);
+ mutex_unlock(&vduse_lock);
+
+ return dev;
+}
+
+static int vduse_dev_open(struct inode *inode, struct file *file)
+{
+ int ret;
+ struct vduse_dev *dev = vduse_dev_get_from_minor(iminor(inode));
+
+ if (!dev)
+ return -ENODEV;
+
+ ret = -EBUSY;
+ mutex_lock(&dev->lock);
+ if (dev->connected)
+ goto unlock;
+
+ ret = 0;
+ dev->connected = true;
+ file->private_data = dev;
+unlock:
+ mutex_unlock(&dev->lock);
+
+ return ret;
+}
+
+static const struct file_operations vduse_dev_fops = {
+ .owner = THIS_MODULE,
+ .open = vduse_dev_open,
+ .release = vduse_dev_release,
+ .read_iter = vduse_dev_read_iter,
+ .write_iter = vduse_dev_write_iter,
+ .poll = vduse_dev_poll,
+ .unlocked_ioctl = vduse_dev_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+ .llseek = noop_llseek,
+};
+
+static struct vduse_dev *vduse_dev_create(void)
+{
+ struct vduse_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+
+ if (!dev)
+ return NULL;
+
+ mutex_init(&dev->lock);
+ spin_lock_init(&dev->msg_lock);
+ INIT_LIST_HEAD(&dev->send_list);
+ INIT_LIST_HEAD(&dev->recv_list);
+ spin_lock_init(&dev->irq_lock);
+
+ INIT_WORK(&dev->inject, vduse_dev_irq_inject);
+ init_waitqueue_head(&dev->waitq);
+
+ return dev;
+}
+
+static void vduse_dev_destroy(struct vduse_dev *dev)
+{
+ kfree(dev);
+}
+
+static struct vduse_dev *vduse_find_dev(const char *name)
+{
+ struct vduse_dev *dev;
+ int id;
+
+ idr_for_each_entry(&vduse_idr, dev, id)
+ if (!strcmp(dev->name, name))
+ return dev;
+
+ return NULL;
+}
+
+static int vduse_destroy_dev(char *name)
+{
+ struct vduse_dev *dev = vduse_find_dev(name);
+
+ if (!dev)
+ return -EINVAL;
+
+ mutex_lock(&dev->lock);
+ if (dev->vdev || dev->connected) {
+ mutex_unlock(&dev->lock);
+ return -EBUSY;
+ }
+ dev->connected = true;
+ mutex_unlock(&dev->lock);
+
+ vduse_dev_reset(dev);
+ device_destroy(vduse_class, MKDEV(MAJOR(vduse_major), dev->minor));
+ idr_remove(&vduse_idr, dev->minor);
+ kvfree(dev->config);
+ kfree(dev->vqs);
+ vduse_domain_destroy(dev->domain);
+ kfree(dev->name);
+ vduse_dev_destroy(dev);
+ module_put(THIS_MODULE);
+
+ return 0;
+}
+
+static bool device_is_allowed(u32 device_id)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(allowed_device_id); i++)
+ if (allowed_device_id[i] == device_id)
+ return true;
+
+ return false;
+}
+
+static bool features_is_valid(u64 features)
+{
+ if (!(features & (1ULL << VIRTIO_F_ACCESS_PLATFORM)))
+ return false;
+
+ /* Now we only support read-only configuration space */
+ if (features & (1ULL << VIRTIO_BLK_F_CONFIG_WCE))
+ return false;
+
+ return true;
+}
+
+static bool vduse_validate_config(struct vduse_dev_config *config)
+{
+ if (!is_mem_zero((const char *)config->reserved,
+ sizeof(config->reserved)))
+ return false;
+
+ if (config->vq_align > PAGE_SIZE)
+ return false;
+
+ if (config->config_size > PAGE_SIZE)
+ return false;
+
+ if (!device_is_allowed(config->device_id))
+ return false;
+
+ if (!features_is_valid(config->features))
+ return false;
+
+ return true;
+}
+
+static ssize_t msg_timeout_show(struct device *device,
+ struct device_attribute *attr, char *buf)
+{
+ struct vduse_dev *dev = dev_get_drvdata(device);
+
+ return sysfs_emit(buf, "%u\n", dev->msg_timeout);
+}
+
+static ssize_t msg_timeout_store(struct device *device,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct vduse_dev *dev = dev_get_drvdata(device);
+ int ret;
+
+ ret = kstrtouint(buf, 10, &dev->msg_timeout);
+ if (ret < 0)
+ return ret;
+
+ return count;
+}
+
+static DEVICE_ATTR_RW(msg_timeout);
+
+static struct attribute *vduse_dev_attrs[] = {
+ &dev_attr_msg_timeout.attr,
+ NULL
+};
+
+ATTRIBUTE_GROUPS(vduse_dev);
+
+static int vduse_create_dev(struct vduse_dev_config *config,
+ void *config_buf, u64 api_version)
+{
+ int i, ret;
+ struct vduse_dev *dev;
+
+ ret = -EEXIST;
+ if (vduse_find_dev(config->name))
+ goto err;
+
+ ret = -ENOMEM;
+ dev = vduse_dev_create();
+ if (!dev)
+ goto err;
+
+ dev->api_version = api_version;
+ dev->device_features = config->features;
+ dev->device_id = config->device_id;
+ dev->vendor_id = config->vendor_id;
+ dev->name = kstrdup(config->name, GFP_KERNEL);
+ if (!dev->name)
+ goto err_str;
+
+ dev->domain = vduse_domain_create(VDUSE_IOVA_SIZE - 1,
+ VDUSE_BOUNCE_SIZE);
+ if (!dev->domain)
+ goto err_domain;
+
+ dev->config = config_buf;
+ dev->config_size = config->config_size;
+ dev->vq_align = config->vq_align;
+ dev->vq_num = config->vq_num;
+ dev->vqs = kcalloc(dev->vq_num, sizeof(*dev->vqs), GFP_KERNEL);
+ if (!dev->vqs)
+ goto err_vqs;
+
+ for (i = 0; i < dev->vq_num; i++) {
+ dev->vqs[i].index = i;
+ INIT_WORK(&dev->vqs[i].inject, vduse_vq_irq_inject);
+ INIT_WORK(&dev->vqs[i].kick, vduse_vq_kick_work);
+ spin_lock_init(&dev->vqs[i].kick_lock);
+ spin_lock_init(&dev->vqs[i].irq_lock);
+ }
+
+ ret = idr_alloc(&vduse_idr, dev, 1, VDUSE_DEV_MAX, GFP_KERNEL);
+ if (ret < 0)
+ goto err_idr;
+
+ dev->minor = ret;
+ dev->msg_timeout = VDUSE_MSG_DEFAULT_TIMEOUT;
+ dev->dev = device_create(vduse_class, NULL,
+ MKDEV(MAJOR(vduse_major), dev->minor),
+ dev, "%s", config->name);
+ if (IS_ERR(dev->dev)) {
+ ret = PTR_ERR(dev->dev);
+ goto err_dev;
+ }
+ __module_get(THIS_MODULE);
+
+ return 0;
+err_dev:
+ idr_remove(&vduse_idr, dev->minor);
+err_idr:
+ kfree(dev->vqs);
+err_vqs:
+ vduse_domain_destroy(dev->domain);
+err_domain:
+ kfree(dev->name);
+err_str:
+ vduse_dev_destroy(dev);
+err:
+ kvfree(config_buf);
+ return ret;
+}
+
+static long vduse_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int ret;
+ void __user *argp = (void __user *)arg;
+ struct vduse_control *control = file->private_data;
+
+ mutex_lock(&vduse_lock);
+ switch (cmd) {
+ case VDUSE_GET_API_VERSION:
+ ret = put_user(control->api_version, (u64 __user *)argp);
+ break;
+ case VDUSE_SET_API_VERSION: {
+ u64 api_version;
+
+ ret = -EFAULT;
+ if (get_user(api_version, (u64 __user *)argp))
+ break;
+
+ ret = -EINVAL;
+ if (api_version > VDUSE_API_VERSION)
+ break;
+
+ ret = 0;
+ control->api_version = api_version;
+ break;
+ }
+ case VDUSE_CREATE_DEV: {
+ struct vduse_dev_config config;
+ unsigned long size = offsetof(struct vduse_dev_config, config);
+ void *buf;
+
+ ret = -EFAULT;
+ if (copy_from_user(&config, argp, size))
+ break;
+
+ ret = -EINVAL;
+ if (vduse_validate_config(&config) == false)
+ break;
+
+ buf = vmemdup_user(argp + size, config.config_size);
+ if (IS_ERR(buf)) {
+ ret = PTR_ERR(buf);
+ break;
+ }
+ config.name[VDUSE_NAME_MAX - 1] = '\0';
+ ret = vduse_create_dev(&config, buf, control->api_version);
+ break;
+ }
+ case VDUSE_DESTROY_DEV: {
+ char name[VDUSE_NAME_MAX];
+
+ ret = -EFAULT;
+ if (copy_from_user(name, argp, VDUSE_NAME_MAX))
+ break;
+
+ name[VDUSE_NAME_MAX - 1] = '\0';
+ ret = vduse_destroy_dev(name);
+ break;
+ }
+ default:
+ ret = -EINVAL;
+ break;
+ }
+ mutex_unlock(&vduse_lock);
+
+ return ret;
+}
+
+static int vduse_release(struct inode *inode, struct file *file)
+{
+ struct vduse_control *control = file->private_data;
+
+ kfree(control);
+ return 0;
+}
+
+static int vduse_open(struct inode *inode, struct file *file)
+{
+ struct vduse_control *control;
+
+ control = kmalloc(sizeof(struct vduse_control), GFP_KERNEL);
+ if (!control)
+ return -ENOMEM;
+
+ control->api_version = VDUSE_API_VERSION;
+ file->private_data = control;
+
+ return 0;
+}
+
+static const struct file_operations vduse_ctrl_fops = {
+ .owner = THIS_MODULE,
+ .open = vduse_open,
+ .release = vduse_release,
+ .unlocked_ioctl = vduse_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+ .llseek = noop_llseek,
+};
+
+static char *vduse_devnode(struct device *dev, umode_t *mode)
+{
+ return kasprintf(GFP_KERNEL, "vduse/%s", dev_name(dev));
+}
+
+static void vduse_mgmtdev_release(struct device *dev)
+{
+}
+
+static struct device vduse_mgmtdev = {
+ .init_name = "vduse",
+ .release = vduse_mgmtdev_release,
+};
+
+static struct vdpa_mgmt_dev mgmt_dev;
+
+static int vduse_dev_init_vdpa(struct vduse_dev *dev, const char *name)
+{
+ struct vduse_vdpa *vdev;
+ int ret;
+
+ if (dev->vdev)
+ return -EEXIST;
+
+ vdev = vdpa_alloc_device(struct vduse_vdpa, vdpa, dev->dev,
+ &vduse_vdpa_config_ops, name, true);
+ if (IS_ERR(vdev))
+ return PTR_ERR(vdev);
+
+ dev->vdev = vdev;
+ vdev->dev = dev;
+ vdev->vdpa.dev.dma_mask = &vdev->vdpa.dev.coherent_dma_mask;
+ ret = dma_set_mask_and_coherent(&vdev->vdpa.dev, DMA_BIT_MASK(64));
+ if (ret) {
+ put_device(&vdev->vdpa.dev);
+ return ret;
+ }
+ set_dma_ops(&vdev->vdpa.dev, &vduse_dev_dma_ops);
+ vdev->vdpa.dma_dev = &vdev->vdpa.dev;
+ vdev->vdpa.mdev = &mgmt_dev;
+
+ return 0;
+}
+
+static int vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name)
+{
+ struct vduse_dev *dev;
+ int ret;
+
+ mutex_lock(&vduse_lock);
+ dev = vduse_find_dev(name);
+ if (!dev || !vduse_dev_is_ready(dev)) {
+ mutex_unlock(&vduse_lock);
+ return -EINVAL;
+ }
+ ret = vduse_dev_init_vdpa(dev, name);
+ mutex_unlock(&vduse_lock);
+ if (ret)
+ return ret;
+
+ ret = _vdpa_register_device(&dev->vdev->vdpa, dev->vq_num);
+ if (ret) {
+ put_device(&dev->vdev->vdpa.dev);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void vdpa_dev_del(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev)
+{
+ _vdpa_unregister_device(dev);
+}
+
+static const struct vdpa_mgmtdev_ops vdpa_dev_mgmtdev_ops = {
+ .dev_add = vdpa_dev_add,
+ .dev_del = vdpa_dev_del,
+};
+
+static struct virtio_device_id id_table[] = {
+ { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID },
+ { 0 },
+};
+
+static struct vdpa_mgmt_dev mgmt_dev = {
+ .device = &vduse_mgmtdev,
+ .id_table = id_table,
+ .ops = &vdpa_dev_mgmtdev_ops,
+};
+
+static int vduse_mgmtdev_init(void)
+{
+ int ret;
+
+ ret = device_register(&vduse_mgmtdev);
+ if (ret)
+ return ret;
+
+ ret = vdpa_mgmtdev_register(&mgmt_dev);
+ if (ret)
+ goto err;
+
+ return 0;
+err:
+ device_unregister(&vduse_mgmtdev);
+ return ret;
+}
+
+static void vduse_mgmtdev_exit(void)
+{
+ vdpa_mgmtdev_unregister(&mgmt_dev);
+ device_unregister(&vduse_mgmtdev);
+}
+
+static int vduse_init(void)
+{
+ int ret;
+ struct device *dev;
+
+ vduse_class = class_create(THIS_MODULE, "vduse");
+ if (IS_ERR(vduse_class))
+ return PTR_ERR(vduse_class);
+
+ vduse_class->devnode = vduse_devnode;
+ vduse_class->dev_groups = vduse_dev_groups;
+
+ ret = alloc_chrdev_region(&vduse_major, 0, VDUSE_DEV_MAX, "vduse");
+ if (ret)
+ goto err_chardev_region;
+
+ /* /dev/vduse/control */
+ cdev_init(&vduse_ctrl_cdev, &vduse_ctrl_fops);
+ vduse_ctrl_cdev.owner = THIS_MODULE;
+ ret = cdev_add(&vduse_ctrl_cdev, vduse_major, 1);
+ if (ret)
+ goto err_ctrl_cdev;
+
+ dev = device_create(vduse_class, NULL, vduse_major, NULL, "control");
+ if (IS_ERR(dev)) {
+ ret = PTR_ERR(dev);
+ goto err_device;
+ }
+
+ /* /dev/vduse/$DEVICE */
+ cdev_init(&vduse_cdev, &vduse_dev_fops);
+ vduse_cdev.owner = THIS_MODULE;
+ ret = cdev_add(&vduse_cdev, MKDEV(MAJOR(vduse_major), 1),
+ VDUSE_DEV_MAX - 1);
+ if (ret)
+ goto err_cdev;
+
+ vduse_irq_wq = alloc_workqueue("vduse-irq",
+ WQ_HIGHPRI | WQ_SYSFS | WQ_UNBOUND, 0);
+ if (!vduse_irq_wq)
+ goto err_wq;
+
+ ret = vduse_domain_init();
+ if (ret)
+ goto err_domain;
+
+ ret = vduse_mgmtdev_init();
+ if (ret)
+ goto err_mgmtdev;
+
+ return 0;
+err_mgmtdev:
+ vduse_domain_exit();
+err_domain:
+ destroy_workqueue(vduse_irq_wq);
+err_wq:
+ cdev_del(&vduse_cdev);
+err_cdev:
+ device_destroy(vduse_class, vduse_major);
+err_device:
+ cdev_del(&vduse_ctrl_cdev);
+err_ctrl_cdev:
+ unregister_chrdev_region(vduse_major, VDUSE_DEV_MAX);
+err_chardev_region:
+ class_destroy(vduse_class);
+ return ret;
+}
+module_init(vduse_init);
+
+static void vduse_exit(void)
+{
+ vduse_mgmtdev_exit();
+ vduse_domain_exit();
+ destroy_workqueue(vduse_irq_wq);
+ cdev_del(&vduse_cdev);
+ device_destroy(vduse_class, vduse_major);
+ cdev_del(&vduse_ctrl_cdev);
+ unregister_chrdev_region(vduse_major, VDUSE_DEV_MAX);
+ class_destroy(vduse_class);
+}
+module_exit(vduse_exit);
+
+MODULE_LICENSE(DRV_LICENSE);
+MODULE_AUTHOR(DRV_AUTHOR);
+MODULE_DESCRIPTION(DRV_DESC);
diff --git a/include/uapi/linux/vduse.h b/include/uapi/linux/vduse.h
new file mode 100644
index 0000000000000000000000000000000000000000..7cfe1c1280c0f2a3fd01edeffac3dc124017829d
--- /dev/null
+++ b/include/uapi/linux/vduse.h
@@ -0,0 +1,306 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _UAPI_VDUSE_H_
+#define _UAPI_VDUSE_H_
+
+#include <linux/types.h>
+
+#define VDUSE_BASE 0x81
+
+/* The ioctls for control device (/dev/vduse/control) */
+
+#define VDUSE_API_VERSION 0
+
+/*
+ * Get the version of VDUSE API that kernel supported (VDUSE_API_VERSION).
+ * This is used for future extension.
+ */
+#define VDUSE_GET_API_VERSION _IOR(VDUSE_BASE, 0x00, __u64)
+
+/* Set the version of VDUSE API that userspace supported. */
+#define VDUSE_SET_API_VERSION _IOW(VDUSE_BASE, 0x01, __u64)
+
+/**
+ * struct vduse_dev_config - basic configuration of a VDUSE device
+ * @name: VDUSE device name, needs to be NUL terminated
+ * @vendor_id: virtio vendor id
+ * @device_id: virtio device id
+ * @features: virtio features
+ * @vq_num: the number of virtqueues
+ * @vq_align: the allocation alignment of virtqueue's metadata
+ * @reserved: for future use, needs to be initialized to zero
+ * @config_size: the size of the configuration space
+ * @config: the buffer of the configuration space
+ *
+ * Structure used by VDUSE_CREATE_DEV ioctl to create VDUSE device.
+ */
+struct vduse_dev_config {
+#define VDUSE_NAME_MAX 256
+ char name[VDUSE_NAME_MAX];
+ __u32 vendor_id;
+ __u32 device_id;
+ __u64 features;
+ __u32 vq_num;
+ __u32 vq_align;
+ __u32 reserved[13];
+ __u32 config_size;
+ __u8 config[];
+};
+
+/* Create a VDUSE device which is represented by a char device (/dev/vduse/$NAME) */
+#define VDUSE_CREATE_DEV _IOW(VDUSE_BASE, 0x02, struct vduse_dev_config)
+
+/*
+ * Destroy a VDUSE device. Make sure there are no more references
+ * to the char device (/dev/vduse/$NAME).
+ */
+#define VDUSE_DESTROY_DEV _IOW(VDUSE_BASE, 0x03, char[VDUSE_NAME_MAX])
+
+/* The ioctls for VDUSE device (/dev/vduse/$NAME) */
+
+/**
+ * struct vduse_iotlb_entry - entry of IOTLB to describe one IOVA region [start, last]
+ * @offset: the mmap offset on returned file descriptor
+ * @start: start of the IOVA region
+ * @last: last of the IOVA region
+ * @perm: access permission of the IOVA region
+ *
+ * Structure used by VDUSE_IOTLB_GET_FD ioctl to find an overlapped IOVA region.
+ */
+struct vduse_iotlb_entry {
+ __u64 offset;
+ __u64 start;
+ __u64 last;
+#define VDUSE_ACCESS_RO 0x1
+#define VDUSE_ACCESS_WO 0x2
+#define VDUSE_ACCESS_RW 0x3
+ __u8 perm;
+};
+
+/*
+ * Find the first IOVA region that overlaps with the range [start, last]
+ * and return the corresponding file descriptor. Return -EINVAL means the
+ * IOVA region doesn't exist. Caller should set start and last fields.
+ */
+#define VDUSE_IOTLB_GET_FD _IOWR(VDUSE_BASE, 0x10, struct vduse_iotlb_entry)
+
+/*
+ * Get the negotiated virtio features. It's a subset of the features in
+ * struct vduse_dev_config which can be accepted by virtio driver. It's
+ * only valid after FEATURES_OK status bit is set.
+ */
+#define VDUSE_DEV_GET_FEATURES _IOR(VDUSE_BASE, 0x11, __u64)
+
+/**
+ * struct vduse_config_data - data used to update configuration space
+ * @offset: the offset from the beginning of configuration space
+ * @length: the length to write to configuration space
+ * @buffer: the buffer used to write from
+ *
+ * Structure used by VDUSE_DEV_SET_CONFIG ioctl to update device
+ * configuration space.
+ */
+struct vduse_config_data {
+ __u32 offset;
+ __u32 length;
+ __u8 buffer[];
+};
+
+/* Set device configuration space */
+#define VDUSE_DEV_SET_CONFIG _IOW(VDUSE_BASE, 0x12, struct vduse_config_data)
+
+/*
+ * Inject a config interrupt. It's usually used to notify virtio driver
+ * that device configuration space has changed.
+ */
+#define VDUSE_DEV_INJECT_CONFIG_IRQ _IO(VDUSE_BASE, 0x13)
+
+/**
+ * struct vduse_vq_config - basic configuration of a virtqueue
+ * @index: virtqueue index
+ * @max_size: the max size of virtqueue
+ * @reserved: for future use, needs to be initialized to zero
+ *
+ * Structure used by VDUSE_VQ_SETUP ioctl to setup a virtqueue.
+ */
+struct vduse_vq_config {
+ __u32 index;
+ __u16 max_size;
+ __u16 reserved[13];
+};
+
+/*
+ * Setup the specified virtqueue. Make sure all virtqueues have been
+ * configured before the device is attached to vDPA bus.
+ */
+#define VDUSE_VQ_SETUP _IOW(VDUSE_BASE, 0x14, struct vduse_vq_config)
+
+/**
+ * struct vduse_vq_state_split - split virtqueue state
+ * @avail_index: available index
+ */
+struct vduse_vq_state_split {
+ __u16 avail_index;
+};
+
+/**
+ * struct vduse_vq_state_packed - packed virtqueue state
+ * @last_avail_counter: last driver ring wrap counter observed by device
+ * @last_avail_idx: device available index
+ * @last_used_counter: device ring wrap counter
+ * @last_used_idx: used index
+ */
+struct vduse_vq_state_packed {
+ __u16 last_avail_counter;
+ __u16 last_avail_idx;
+ __u16 last_used_counter;
+ __u16 last_used_idx;
+};
+
+/**
+ * struct vduse_vq_info - information of a virtqueue
+ * @index: virtqueue index
+ * @num: the size of virtqueue
+ * @desc_addr: address of desc area
+ * @driver_addr: address of driver area
+ * @device_addr: address of device area
+ * @split: split virtqueue state
+ * @packed: packed virtqueue state
+ * @ready: ready status of virtqueue
+ *
+ * Structure used by VDUSE_VQ_GET_INFO ioctl to get virtqueue's information.
+ */
+struct vduse_vq_info {
+ __u32 index;
+ __u32 num;
+ __u64 desc_addr;
+ __u64 driver_addr;
+ __u64 device_addr;
+ union {
+ struct vduse_vq_state_split split;
+ struct vduse_vq_state_packed packed;
+ };
+ __u8 ready;
+};
+
+/* Get the specified virtqueue's information. Caller should set index field. */
+#define VDUSE_VQ_GET_INFO _IOWR(VDUSE_BASE, 0x15, struct vduse_vq_info)
+
+/**
+ * struct vduse_vq_eventfd - eventfd configuration for a virtqueue
+ * @index: virtqueue index
+ * @fd: eventfd, -1 means de-assigning the eventfd
+ *
+ * Structure used by VDUSE_VQ_SETUP_KICKFD ioctl to setup kick eventfd.
+ */
+struct vduse_vq_eventfd {
+ __u32 index;
+#define VDUSE_EVENTFD_DEASSIGN -1
+ int fd;
+};
+
+/*
+ * Setup kick eventfd for specified virtqueue. The kick eventfd is used
+ * by VDUSE kernel module to notify userspace to consume the avail vring.
+ */
+#define VDUSE_VQ_SETUP_KICKFD _IOW(VDUSE_BASE, 0x16, struct vduse_vq_eventfd)
+
+/*
+ * Inject an interrupt for specific virtqueue. It's used to notify virtio driver
+ * to consume the used vring.
+ */
+#define VDUSE_VQ_INJECT_IRQ _IOW(VDUSE_BASE, 0x17, __u32)
+
+/* The control messages definition for read(2)/write(2) on /dev/vduse/$NAME */
+
+/**
+ * enum vduse_req_type - request type
+ * @VDUSE_GET_VQ_STATE: get the state for specified virtqueue from userspace
+ * @VDUSE_SET_STATUS: set the device status
+ * @VDUSE_UPDATE_IOTLB: Notify userspace to update the memory mapping for
+ * specified IOVA range via VDUSE_IOTLB_GET_FD ioctl
+ */
+enum vduse_req_type {
+ VDUSE_GET_VQ_STATE,
+ VDUSE_SET_STATUS,
+ VDUSE_UPDATE_IOTLB,
+};
+
+/**
+ * struct vduse_vq_state - virtqueue state
+ * @index: virtqueue index
+ * @split: split virtqueue state
+ * @packed: packed virtqueue state
+ */
+struct vduse_vq_state {
+ __u32 index;
+ union {
+ struct vduse_vq_state_split split;
+ struct vduse_vq_state_packed packed;
+ };
+};
+
+/**
+ * struct vduse_dev_status - device status
+ * @status: device status
+ */
+struct vduse_dev_status {
+ __u8 status;
+};
+
+/**
+ * struct vduse_iova_range - IOVA range [start, last]
+ * @start: start of the IOVA range
+ * @last: last of the IOVA range
+ */
+struct vduse_iova_range {
+ __u64 start;
+ __u64 last;
+};
+
+/**
+ * struct vduse_dev_request - control request
+ * @type: request type
+ * @request_id: request id
+ * @reserved: for future use
+ * @vq_state: virtqueue state, only index field is available
+ * @s: device status
+ * @iova: IOVA range for updating
+ * @padding: padding
+ *
+ * Structure used by read(2) on /dev/vduse/$NAME.
+ */
+struct vduse_dev_request {
+ __u32 type;
+ __u32 request_id;
+ __u32 reserved[4];
+ union {
+ struct vduse_vq_state vq_state;
+ struct vduse_dev_status s;
+ struct vduse_iova_range iova;
+ __u32 padding[32];
+ };
+};
+
+/**
+ * struct vduse_dev_response - response to control request
+ * @request_id: corresponding request id
+ * @result: the result of request
+ * @reserved: for future use, needs to be initialized to zero
+ * @vq_state: virtqueue state
+ * @padding: padding
+ *
+ * Structure used by write(2) on /dev/vduse/$NAME.
+ */
+struct vduse_dev_response {
+ __u32 request_id;
+#define VDUSE_REQ_RESULT_OK 0x00
+#define VDUSE_REQ_RESULT_FAILED 0x01
+ __u32 result;
+ __u32 reserved[4];
+ union {
+ struct vduse_vq_state vq_state;
+ __u32 padding[32];
+ };
+};
+
+#endif /* _UAPI_VDUSE_H_ */