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WSL2-Linux-Kernel
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WSL2-Linux-Kernel/drivers/vdpa/vdpa_user/vduse_dev.c

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37 KiB
C
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// 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;
struct rw_semaphore rwsem;
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);
down_write(&dev->rwsem);
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);
}
up_write(&dev->rwsem);
}
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];
if (!eventfd_signal_allowed()) {
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);
/* Initialize the buffer in case of partial copy. */
memset(buf, 0, len);
if (offset > dev->config_size)
return;
if (len > dev->config_size - offset)
len = dev->config_size - offset;
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);
int ret = vduse_dev_set_status(dev, 0);
vduse_dev_reset(dev);
return ret;
}
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 int vduse_dev_queue_irq_work(struct vduse_dev *dev,
struct work_struct *irq_work)
{
int ret = -EINVAL;
down_read(&dev->rwsem);
if (!(dev->status & VIRTIO_CONFIG_S_DRIVER_OK))
goto unlock;
ret = 0;
queue_work(vduse_irq_wq, irq_work);
unlock:
up_read(&dev->rwsem);
return ret;
}
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.offset > dev->config_size ||
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 = vduse_dev_queue_irq_work(dev, &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;
index = array_index_nospec(index, dev->vq_num);
ret = vduse_dev_queue_irq_work(dev, &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_rwsem(&dev->rwsem);
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 (config->vq_num > 0xffff)
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_with_groups(vduse_class, NULL,
MKDEV(MAJOR(vduse_major), dev->minor),
dev, vduse_dev_groups, "%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));
}
struct vduse_mgmt_dev {
struct vdpa_mgmt_dev mgmt_dev;
struct device dev;
};
static struct vduse_mgmt_dev *vduse_mgmt;
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 = &vduse_mgmt->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 void vduse_mgmtdev_release(struct device *dev)
{
struct vduse_mgmt_dev *mgmt_dev;
mgmt_dev = container_of(dev, struct vduse_mgmt_dev, dev);
kfree(mgmt_dev);
}
static int vduse_mgmtdev_init(void)
{
int ret;
vduse_mgmt = kzalloc(sizeof(*vduse_mgmt), GFP_KERNEL);
if (!vduse_mgmt)
return -ENOMEM;
ret = dev_set_name(&vduse_mgmt->dev, "vduse");
if (ret) {
kfree(vduse_mgmt);
return ret;
}
vduse_mgmt->dev.release = vduse_mgmtdev_release;
ret = device_register(&vduse_mgmt->dev);
if (ret)
goto dev_reg_err;
vduse_mgmt->mgmt_dev.id_table = id_table;
vduse_mgmt->mgmt_dev.ops = &vdpa_dev_mgmtdev_ops;
vduse_mgmt->mgmt_dev.device = &vduse_mgmt->dev;
ret = vdpa_mgmtdev_register(&vduse_mgmt->mgmt_dev);
if (ret)
device_unregister(&vduse_mgmt->dev);
return ret;
dev_reg_err:
put_device(&vduse_mgmt->dev);
return ret;
}
static void vduse_mgmtdev_exit(void)
{
vdpa_mgmtdev_unregister(&vduse_mgmt->mgmt_dev);
device_unregister(&vduse_mgmt->dev);
}
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;
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) {
ret = -ENOMEM;
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);
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