From: Jason Wang <jasowang@redhat.com>
To: Xie Yongji <xieyongji@bytedance.com>,
mst@redhat.com, stefanha@redhat.com, sgarzare@redhat.com,
parav@nvidia.com, bob.liu@oracle.com, hch@infradead.org,
rdunlap@infradead.org, willy@infradead.org,
viro@zeniv.linux.org.uk, axboe@kernel.dk, bcrl@kvack.org,
corbet@lwn.net
Cc: virtualization@lists.linux-foundation.org,
netdev@vger.kernel.org, kvm@vger.kernel.org, linux-aio@kvack.org,
linux-fsdevel@vger.kernel.org
Subject: Re: [RFC v4 07/11] vduse: Introduce VDUSE - vDPA Device in Userspace
Date: Thu, 4 Mar 2021 14:27:21 +0800 [thread overview]
Message-ID: <da57a29a-9860-f72f-36d6-252b45fe03f7@redhat.com> (raw)
In-Reply-To: <20210223115048.435-8-xieyongji@bytedance.com>
On 2021/2/23 7:50 下午, Xie Yongji wrote:
> This VDUSE driver enables implementing vDPA devices in userspace.
> Both control path and data path of vDPA devices will be able to
> be handled in userspace.
>
> In the control path, the VDUSE driver will make use of message
> mechnism to forward the config operation from vdpa bus driver
> to userspace. Userspace can use read()/write() to receive/reply
> those control messages.
>
> In the data path, VDUSE_IOTLB_GET_FD ioctl will be used to get
> the file descriptors referring to vDPA device's iova regions. Then
> userspace can use mmap() to access those iova regions. Besides,
> userspace can use ioctl() to inject interrupt and use the eventfd
> mechanism to receive virtqueue kicks.
>
> Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
> ---
> Documentation/userspace-api/ioctl/ioctl-number.rst | 1 +
> drivers/vdpa/Kconfig | 10 +
> drivers/vdpa/Makefile | 1 +
> drivers/vdpa/vdpa_user/Makefile | 5 +
> drivers/vdpa/vdpa_user/vduse_dev.c | 1348 ++++++++++++++++++++
> include/uapi/linux/vduse.h | 136 ++
> 6 files changed, 1501 insertions(+)
> create mode 100644 drivers/vdpa/vdpa_user/Makefile
> create mode 100644 drivers/vdpa/vdpa_user/vduse_dev.c
> create mode 100644 include/uapi/linux/vduse.h
>
> diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
> index a4c75a28c839..71722e6f8f23 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 ffd1e098bfd2..92f07715e3b6 100644
> --- a/drivers/vdpa/Kconfig
> +++ b/drivers/vdpa/Kconfig
> @@ -25,6 +25,16 @@ config VDPA_SIM_NET
> help
> vDPA networking device simulator which loops TX traffic back to RX.
>
> +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 d160e9b63a66..66e97778ad03 100644
> --- a/drivers/vdpa/Makefile
> +++ b/drivers/vdpa/Makefile
> @@ -1,5 +1,6 @@
> # 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-$(CONFIG_MLX5_VDPA) += mlx5/
> diff --git a/drivers/vdpa/vdpa_user/Makefile b/drivers/vdpa/vdpa_user/Makefile
> new file mode 100644
> index 000000000000..260e0b26af99
> --- /dev/null
> +++ b/drivers/vdpa/vdpa_user/Makefile
> @@ -0,0 +1,5 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +vduse-y := vduse_dev.o iova_domain.o
> +
> +obj-$(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 000000000000..393bf99c48be
> --- /dev/null
> +++ b/drivers/vdpa/vdpa_user/vduse_dev.c
> @@ -0,0 +1,1348 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * VDUSE: vDPA Device in Userspace
> + *
> + * Copyright (C) 2020 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/miscdevice.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 <uapi/linux/vduse.h>
> +#include <uapi/linux/vdpa.h>
> +#include <uapi/linux/virtio_config.h>
> +#include <linux/mod_devicetable.h>
> +
> +#include "iova_domain.h"
> +
> +#define DRV_VERSION "1.0"
> +#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)
> +
> +struct vduse_virtqueue {
> + u16 index;
> + bool ready;
> + spinlock_t kick_lock;
> + spinlock_t irq_lock;
> + struct eventfd_ctx *kickfd;
> + struct vdpa_callback cb;
> +};
> +
> +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 cdev cdev;
> + struct vduse_virtqueue *vqs;
> + struct vduse_iova_domain *domain;
> + struct vhost_iotlb *iommu;
> + spinlock_t iommu_lock;
> + atomic_t bounce_map;
> + struct mutex msg_lock;
> + atomic64_t msg_unique;
"next_request_id" should be better.
> + wait_queue_head_t waitq;
> + struct list_head send_list;
> + struct list_head recv_list;
> + struct list_head list;
> + bool connected;
> + int minor;
> + u16 vq_size_max;
> + u16 vq_num;
> + u32 vq_align;
> + u32 device_id;
> + u32 vendor_id;
> +};
> +
> +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;
> +};
> +
> +static unsigned long max_bounce_size = (64 * 1024 * 1024);
> +module_param(max_bounce_size, ulong, 0444);
> +MODULE_PARM_DESC(max_bounce_size, "Maximum bounce buffer size. (default: 64M)");
> +
> +static unsigned long max_iova_size = (128 * 1024 * 1024);
> +module_param(max_iova_size, ulong, 0444);
> +MODULE_PARM_DESC(max_iova_size, "Maximum iova space size (default: 128M)");
> +
> +static DEFINE_MUTEX(vduse_lock);
> +static LIST_HEAD(vduse_devs);
> +static DEFINE_IDA(vduse_ida);
> +
> +static dev_t vduse_major;
> +static struct class *vduse_class;
> +
> +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 unique)
> +{
> + struct vduse_dev_msg *tmp, *msg = NULL;
> +
> + list_for_each_entry(tmp, head, list) {
Shoudl we use list_for_each_entry_safe()?
> + if (tmp->req.unique == unique) {
> + msg = tmp;
> + list_del(&tmp->list);
> + break;
> + }
> + }
> +
> + return msg;
> +}
> +
> +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 int vduse_dev_msg_sync(struct vduse_dev *dev, struct vduse_dev_msg *msg)
> +{
> + int ret;
> +
> + init_waitqueue_head(&msg->waitq);
> + mutex_lock(&dev->msg_lock);
> + vduse_enqueue_msg(&dev->send_list, msg);
> + wake_up(&dev->waitq);
> + mutex_unlock(&dev->msg_lock);
> + ret = wait_event_interruptible(msg->waitq, msg->completed);
> + mutex_lock(&dev->msg_lock);
> + if (!msg->completed)
> + list_del(&msg->list);
> + else
> + ret = msg->resp.result;
> + mutex_unlock(&dev->msg_lock);
> +
> + return ret;
> +}
> +
> +static u64 vduse_dev_get_features(struct vduse_dev *dev)
> +{
> + struct vduse_dev_msg msg = { 0 };
> +
> + msg.req.type = VDUSE_GET_FEATURES;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> +
> + return vduse_dev_msg_sync(dev, &msg) ? 0 : msg.resp.features;
> +}
> +
> +static int vduse_dev_set_features(struct vduse_dev *dev, u64 features)
> +{
> + struct vduse_dev_msg msg = { 0 };
> +
> + msg.req.type = VDUSE_SET_FEATURES;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> + msg.req.features = features;
> +
> + return vduse_dev_msg_sync(dev, &msg);
> +}
> +
> +static u8 vduse_dev_get_status(struct vduse_dev *dev)
> +{
> + struct vduse_dev_msg msg = { 0 };
> +
> + msg.req.type = VDUSE_GET_STATUS;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> +
> + return vduse_dev_msg_sync(dev, &msg) ? 0 : msg.resp.status;
> +}
> +
> +static void vduse_dev_set_status(struct vduse_dev *dev, u8 status)
> +{
> + struct vduse_dev_msg msg = { 0 };
> +
> + msg.req.type = VDUSE_SET_STATUS;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> + msg.req.status = status;
> +
> + vduse_dev_msg_sync(dev, &msg);
> +}
> +
> +static void vduse_dev_get_config(struct vduse_dev *dev, unsigned int offset,
> + void *buf, unsigned int len)
Btw, the ident looks odd here and other may places wherhe functions has
more than one line of arguments.
> +{
> + struct vduse_dev_msg msg = { 0 };
> + unsigned int sz;
> +
> + while (len) {
> + sz = min_t(unsigned int, len, sizeof(msg.req.config.data));
> + msg.req.type = VDUSE_GET_CONFIG;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> + msg.req.config.offset = offset;
> + msg.req.config.len = sz;
> + vduse_dev_msg_sync(dev, &msg);
> + memcpy(buf, msg.resp.config.data, sz);
> + buf += sz;
> + offset += sz;
> + len -= sz;
> + }
> +}
> +
> +static void vduse_dev_set_config(struct vduse_dev *dev, unsigned int offset,
> + const void *buf, unsigned int len)
> +{
> + struct vduse_dev_msg msg = { 0 };
> + unsigned int sz;
> +
> + while (len) {
> + sz = min_t(unsigned int, len, sizeof(msg.req.config.data));
> + msg.req.type = VDUSE_SET_CONFIG;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> + msg.req.config.offset = offset;
> + msg.req.config.len = sz;
> + memcpy(msg.req.config.data, buf, sz);
> + vduse_dev_msg_sync(dev, &msg);
> + buf += sz;
> + offset += sz;
> + len -= sz;
> + }
> +}
> +
> +static void vduse_dev_set_vq_num(struct vduse_dev *dev,
> + struct vduse_virtqueue *vq, u32 num)
> +{
> + struct vduse_dev_msg msg = { 0 };
> +
> + msg.req.type = VDUSE_SET_VQ_NUM;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> + msg.req.vq_num.index = vq->index;
> + msg.req.vq_num.num = num;
> +
> + vduse_dev_msg_sync(dev, &msg);
> +}
> +
> +static int vduse_dev_set_vq_addr(struct vduse_dev *dev,
> + struct vduse_virtqueue *vq, u64 desc_addr,
> + u64 driver_addr, u64 device_addr)
> +{
> + struct vduse_dev_msg msg = { 0 };
> +
> + msg.req.type = VDUSE_SET_VQ_ADDR;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> + msg.req.vq_addr.index = vq->index;
> + msg.req.vq_addr.desc_addr = desc_addr;
> + msg.req.vq_addr.driver_addr = driver_addr;
> + msg.req.vq_addr.device_addr = device_addr;
> +
> + return vduse_dev_msg_sync(dev, &msg);
> +}
> +
> +static void vduse_dev_set_vq_ready(struct vduse_dev *dev,
> + struct vduse_virtqueue *vq, bool ready)
> +{
> + struct vduse_dev_msg msg = { 0 };
> +
> + msg.req.type = VDUSE_SET_VQ_READY;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> + msg.req.vq_ready.index = vq->index;
> + msg.req.vq_ready.ready = ready;
> +
> + vduse_dev_msg_sync(dev, &msg);
> +}
> +
> +static bool vduse_dev_get_vq_ready(struct vduse_dev *dev,
> + struct vduse_virtqueue *vq)
> +{
> + struct vduse_dev_msg msg = { 0 };
> +
> + msg.req.type = VDUSE_GET_VQ_READY;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> + msg.req.vq_ready.index = vq->index;
> +
> + return vduse_dev_msg_sync(dev, &msg) ? false : msg.resp.vq_ready.ready;
> +}
> +
> +static int vduse_dev_get_vq_state(struct vduse_dev *dev,
> + struct vduse_virtqueue *vq,
> + struct vdpa_vq_state *state)
> +{
> + struct vduse_dev_msg msg = { 0 };
> + int ret;
> +
> + msg.req.type = VDUSE_GET_VQ_STATE;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> + msg.req.vq_state.index = vq->index;
> +
> + ret = vduse_dev_msg_sync(dev, &msg);
> + if (!ret)
> + state->avail_index = msg.resp.vq_state.avail_idx;
> +
> + return ret;
> +}
> +
> +static int vduse_dev_set_vq_state(struct vduse_dev *dev,
> + struct vduse_virtqueue *vq,
> + const struct vdpa_vq_state *state)
> +{
> + struct vduse_dev_msg msg = { 0 };
> +
> + msg.req.type = VDUSE_SET_VQ_STATE;
> + msg.req.unique = atomic64_fetch_inc(&dev->msg_unique);
> + msg.req.vq_state.index = vq->index;
> + msg.req.vq_state.avail_idx = state->avail_index;
> +
> + 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.unique = atomic64_fetch_inc(&dev->msg_unique);
> + 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 = 0;
> +
> + if (iov_iter_count(to) < size)
> + return 0;
> +
> + mutex_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;
> +
> + mutex_unlock(&dev->msg_lock);
> + ret = wait_event_interruptible_exclusive(dev->waitq,
> + !list_empty(&dev->send_list));
> + if (ret)
> + return ret;
> +
> + mutex_lock(&dev->msg_lock);
> + }
> + ret = copy_to_iter(&msg->req, size, to);
> + if (ret != size) {
> + ret = -EFAULT;
> + vduse_enqueue_msg(&dev->send_list, msg);
> + goto unlock;
> + }
> + vduse_enqueue_msg(&dev->recv_list, msg);
> +unlock:
> + mutex_unlock(&dev->msg_lock);
> +
> + return ret;
> +}
> +
> +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;
> +
> + mutex_lock(&dev->msg_lock);
> + msg = vduse_find_msg(&dev->recv_list, resp.request_id);
> + if (!msg) {
> + ret = -EINVAL;
> + goto unlock;
> + }
> +
> + memcpy(&msg->resp, &resp, sizeof(resp));
> + msg->completed = 1;
> + wake_up(&msg->waitq);
> +unlock:
> + mutex_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);
> +
> + if (!list_empty(&dev->send_list))
> + mask |= EPOLLIN | EPOLLRDNORM;
> +
> + return mask;
> +}
> +
> +static int vduse_iotlb_add_range(struct vduse_dev *dev,
> + u64 start, u64 last,
> + u64 addr, unsigned int perm,
> + struct file *file, u64 offset)
> +{
> + struct vdpa_map_file *map_file;
> + int ret;
> +
> + map_file = kmalloc(sizeof(*map_file), GFP_ATOMIC);
> + if (!map_file)
> + return -ENOMEM;
> +
> + map_file->file = get_file(file);
> + map_file->offset = offset;
> +
> + spin_lock(&dev->iommu_lock);
> + ret = vhost_iotlb_add_range_ctx(dev->iommu, start, last,
> + addr, perm, map_file);
> + spin_unlock(&dev->iommu_lock);
> + if (ret) {
> + fput(map_file->file);
> + kfree(map_file);
> + return ret;
> + }
> + return 0;
> +}
> +
> +static void vduse_iotlb_del_range(struct vduse_dev *dev, u64 start, u64 last)
> +{
> + struct vdpa_map_file *map_file;
> + struct vhost_iotlb_map *map;
> +
> + spin_lock(&dev->iommu_lock);
> + while ((map = vhost_iotlb_itree_first(dev->iommu, start, last))) {
> + map_file = (struct vdpa_map_file *)map->opaque;
> + fput(map_file->file);
> + kfree(map_file);
> + vhost_iotlb_map_free(dev->iommu, map);
> + }
> + spin_unlock(&dev->iommu_lock);
> +}
> +
> +static void vduse_dev_reset(struct vduse_dev *dev)
> +{
> + int i;
> +
> + atomic_set(&dev->bounce_map, 0);
> + vduse_iotlb_del_range(dev, 0ULL, ULLONG_MAX);
> + vduse_dev_update_iotlb(dev, 0ULL, ULLONG_MAX);
> +
> + for (i = 0; i < dev->vq_num; i++) {
> + struct vduse_virtqueue *vq = &dev->vqs[i];
> +
> + spin_lock(&vq->irq_lock);
> + vq->ready = false;
> + vq->cb.callback = NULL;
> + vq->cb.private = NULL;
> + spin_unlock(&vq->irq_lock);
> + }
> +}
> +
> +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];
> +
> + return vduse_dev_set_vq_addr(dev, vq, desc_area,
> + driver_area, device_area);
> +}
> +
> +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];
> +
> + spin_lock(&vq->kick_lock);
> + if (vq->ready && vq->kickfd)
> + eventfd_signal(vq->kickfd, 1);
> + spin_unlock(&vq->kick_lock);
> +}
> +
> +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];
> +
> + vduse_dev_set_vq_num(dev, vq, 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];
> +
> + vduse_dev_set_vq_ready(dev, vq, ready);
> + 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];
> +
> + vq->ready = vduse_dev_get_vq_ready(dev, vq);
> +
> + 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];
> +
> + return vduse_dev_set_vq_state(dev, vq, state);
> +}
> +
> +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];
> +
> + return vduse_dev_get_vq_state(dev, vq, state);
> +}
> +
> +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);
> + u64 fixed = (1ULL << VIRTIO_F_ACCESS_PLATFORM);
> +
> + return (vduse_dev_get_features(dev) | fixed);
What happens if we don't do such fixup. I think we should fail if
usersapce doesnt offer ACCESS_PLATFORM instead.
> +}
> +
> +static int vduse_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
> +{
> + struct vduse_dev *dev = vdpa_to_vduse(vdpa);
> +
> + return vduse_dev_set_features(dev, features);
> +}
> +
> +static void vduse_vdpa_set_config_cb(struct vdpa_device *vdpa,
> + struct vdpa_callback *cb)
> +{
> + /* We don't support config interrupt */
> +}
> +
> +static u16 vduse_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
> +{
> + struct vduse_dev *dev = vdpa_to_vduse(vdpa);
> +
> + return dev->vq_size_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 vduse_dev_get_status(dev);
> +}
> +
> +static void vduse_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
> +{
> + struct vduse_dev *dev = vdpa_to_vduse(vdpa);
> +
> + if (status == 0)
> + vduse_dev_reset(dev);
> +
> + vduse_dev_set_status(dev, status);
> +}
> +
> +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);
> +
> + vduse_dev_get_config(dev, offset, buf, len);
> +}
> +
> +static void vduse_vdpa_set_config(struct vdpa_device *vdpa, unsigned int offset,
> + const void *buf, unsigned int len)
> +{
> + struct vduse_dev *dev = vdpa_to_vduse(vdpa);
> +
> + vduse_dev_set_config(dev, offset, buf, len);
> +}
> +
> +static int vduse_vdpa_set_map(struct vdpa_device *vdpa,
> + struct vhost_iotlb *iotlb)
> +{
> + struct vduse_dev *dev = vdpa_to_vduse(vdpa);
> + struct vhost_iotlb_map *map;
> + struct vdpa_map_file *map_file;
> + u64 start = 0ULL, last = ULLONG_MAX;
> + int ret = 0;
> +
> + vduse_iotlb_del_range(dev, start, last);
> +
> + for (map = vhost_iotlb_itree_first(iotlb, start, last); map;
> + map = vhost_iotlb_itree_next(map, start, last)) {
> + map_file = (struct vdpa_map_file *)map->opaque;
> + if (!map_file->file)
> + continue;
> +
> + ret = vduse_iotlb_add_range(dev, map->start, map->last,
> + map->addr, map->perm,
> + map_file->file,
> + map_file->offset);
> + if (ret)
> + break;
> + }
> + vduse_dev_update_iotlb(dev, start, last);
> +
> + return ret;
> +}
> +
> +static void vduse_vdpa_free(struct vdpa_device *vdpa)
> +{
> + struct vduse_dev *dev = vdpa_to_vduse(vdpa);
> +
> + WARN_ON(!list_empty(&dev->send_list));
> + WARN_ON(!list_empty(&dev->recv_list));
> + 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 = vduse_vdpa_get_config,
> + .set_config = vduse_vdpa_set_config,
> + .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;
> +
> + if (atomic_xchg(&vdev->bounce_map, 1) == 0 &&
> + vduse_iotlb_add_range(vdev, 0, domain->bounce_size - 1,
> + 0, VDUSE_ACCESS_RW,
> + vduse_domain_file(domain), 0)) {
> + atomic_set(&vdev->bounce_map, 0);
> + return DMA_MAPPING_ERROR;
Can we add the bounce mapping page by page here?
> + }
> +
> + 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;
> +
> + if (vduse_iotlb_add_range(vdev, iova, iova + size - 1,
> + iova, VDUSE_ACCESS_RW,
> + vduse_domain_file(domain), iova)) {
> + vduse_domain_free_coherent(domain, size, addr, iova, attrs);
> + 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;
> + unsigned long start = (unsigned long)dma_addr;
> + unsigned long last = start + size - 1;
> +
> + vduse_iotlb_del_range(vdev, start, last);
> + vduse_dev_update_iotlb(vdev, start, last);
> + vduse_domain_free_coherent(domain, size, vaddr, dma_addr, attrs);
> +}
> +
> +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,
> +};
> +
> +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;
> +
> + if (eventfd->index >= dev->vq_num)
> + return -EINVAL;
> +
> + vq = &dev->vqs[eventfd->index];
> + if (eventfd->fd > 0) {
> + ctx = eventfd_ctx_fdget(eventfd->fd);
> + if (IS_ERR(ctx))
> + return PTR_ERR(ctx);
> + }
> + spin_lock(&vq->kick_lock);
> + if (vq->kickfd)
> + eventfd_ctx_put(vq->kickfd);
> + vq->kickfd = ctx;
> + spin_unlock(&vq->kick_lock);
> +
> + return 0;
> +}
> +
> +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;
> +
> + switch (cmd) {
> + case VDUSE_IOTLB_GET_FD: {
> + struct vduse_iotlb_entry entry;
> + struct vhost_iotlb_map *map;
> + struct vdpa_map_file *map_file;
> + struct file *f = NULL;
> +
> + ret = -EFAULT;
> + if (copy_from_user(&entry, argp, sizeof(entry)))
> + break;
> +
> + spin_lock(&dev->iommu_lock);
> + map = vhost_iotlb_itree_first(dev->iommu, 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(&dev->iommu_lock);
> + if (!f) {
> + ret = -EINVAL;
> + break;
> + }
> + if (copy_to_user(argp, &entry, sizeof(entry))) {
> + fput(f);
> + ret = -EFAULT;
> + break;
> + }
> + ret = get_unused_fd_flags(perm_to_file_flags(entry.perm));
> + if (ret < 0) {
> + fput(f);
> + break;
> + }
> + fd_install(ret, f);
> + 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_INJECT_VQ_IRQ: {
> + struct vduse_virtqueue *vq;
> +
> + ret = -EINVAL;
> + if (arg >= dev->vq_num)
> + break;
> +
> + vq = &dev->vqs[arg];
> + spin_lock_irq(&vq->irq_lock);
> + if (vq->ready && vq->cb.callback) {
> + vq->cb.callback(vq->cb.private);
> + ret = 0;
> + }
> + spin_unlock_irq(&vq->irq_lock);
> + 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;
> + struct vduse_dev_msg *msg;
> + int i;
> +
> + for (i = 0; i < dev->vq_num; i++) {
> + struct vduse_virtqueue *vq = &dev->vqs[i];
> +
> + spin_lock(&vq->kick_lock);
> + if (vq->kickfd)
> + eventfd_ctx_put(vq->kickfd);
> + vq->kickfd = NULL;
> + spin_unlock(&vq->kick_lock);
> + }
> +
> + mutex_lock(&dev->msg_lock);
> + while ((msg = vduse_dequeue_msg(&dev->recv_list)))
> + vduse_enqueue_msg(&dev->send_list, msg);
> + mutex_unlock(&dev->msg_lock);
> +
> + dev->connected = false;
> +
> + return 0;
> +}
> +
> +static int vduse_dev_open(struct inode *inode, struct file *file)
> +{
> + struct vduse_dev *dev = container_of(inode->i_cdev,
> + struct vduse_dev, cdev);
> + int ret = -EBUSY;
> +
> + mutex_lock(&vduse_lock);
> + if (dev->connected)
> + goto unlock;
> +
> + ret = 0;
> + dev->connected = true;
> + file->private_data = dev;
> +unlock:
> + mutex_unlock(&vduse_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;
> +
> + dev->iommu = vhost_iotlb_alloc(0, 0);
> + if (!dev->iommu) {
> + kfree(dev);
> + return NULL;
> + }
> +
> + mutex_init(&dev->msg_lock);
> + INIT_LIST_HEAD(&dev->send_list);
> + INIT_LIST_HEAD(&dev->recv_list);
> + atomic64_set(&dev->msg_unique, 0);
> + spin_lock_init(&dev->iommu_lock);
> + atomic_set(&dev->bounce_map, 0);
> +
> + init_waitqueue_head(&dev->waitq);
> +
> + return dev;
> +}
> +
> +static void vduse_dev_destroy(struct vduse_dev *dev)
> +{
> + vhost_iotlb_free(dev->iommu);
> + mutex_destroy(&dev->msg_lock);
> + kfree(dev);
> +}
> +
> +static struct vduse_dev *vduse_find_dev(const char *name)
> +{
> + struct vduse_dev *tmp, *dev = NULL;
> +
> + list_for_each_entry(tmp, &vduse_devs, list) {
> + if (!strcmp(dev_name(&tmp->dev), name)) {
> + dev = tmp;
> + break;
> + }
> + }
> + return dev;
> +}
> +
> +static int vduse_destroy_dev(char *name)
> +{
> + struct vduse_dev *dev = vduse_find_dev(name);
> +
> + if (!dev)
> + return -EINVAL;
> +
> + if (dev->vdev || dev->connected)
> + return -EBUSY;
> +
> + dev->connected = true;
> + list_del(&dev->list);
> + cdev_device_del(&dev->cdev, &dev->dev);
> + put_device(&dev->dev);
> +
> + return 0;
> +}
> +
> +static void vduse_release_dev(struct device *device)
> +{
> + struct vduse_dev *dev =
> + container_of(device, struct vduse_dev, dev);
> +
> + ida_simple_remove(&vduse_ida, dev->minor);
> + kfree(dev->vqs);
> + vduse_domain_destroy(dev->domain);
> + vduse_dev_destroy(dev);
> + module_put(THIS_MODULE);
> +}
> +
> +static int vduse_create_dev(struct vduse_dev_config *config)
> +{
> + int i, ret = -ENOMEM;
> + struct vduse_dev *dev;
> +
> + if (config->bounce_size > max_bounce_size)
> + return -EINVAL;
> +
> + if (config->bounce_size > max_iova_size)
> + return -EINVAL;
> +
> + if (vduse_find_dev(config->name))
> + return -EEXIST;
> +
> + dev = vduse_dev_create();
> + if (!dev)
> + return -ENOMEM;
> +
> + dev->device_id = config->device_id;
> + dev->vendor_id = config->vendor_id;
> + dev->domain = vduse_domain_create(max_iova_size - 1,
> + config->bounce_size);
> + if (!dev->domain)
> + goto err_domain;
> +
> + dev->vq_align = config->vq_align;
> + dev->vq_size_max = config->vq_size_max;
> + 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;
> + spin_lock_init(&dev->vqs[i].kick_lock);
> + spin_lock_init(&dev->vqs[i].irq_lock);
> + }
> +
> + ret = ida_simple_get(&vduse_ida, 0, VDUSE_DEV_MAX, GFP_KERNEL);
> + if (ret < 0)
> + goto err_ida;
> +
> + dev->minor = ret;
> + device_initialize(&dev->dev);
> + dev->dev.release = vduse_release_dev;
> + dev->dev.class = vduse_class;
> + dev->dev.devt = MKDEV(MAJOR(vduse_major), dev->minor);
> + ret = dev_set_name(&dev->dev, "%s", config->name);
Do we need to add a namespce here? E.g "vduse-%s", config->name.
> + if (ret)
> + goto err_name;
> +
> + cdev_init(&dev->cdev, &vduse_dev_fops);
> + dev->cdev.owner = THIS_MODULE;
> +
> + ret = cdev_device_add(&dev->cdev, &dev->dev);
> + if (ret) {
> + put_device(&dev->dev);
> + return ret;
> + }
> + list_add(&dev->list, &vduse_devs);
> + __module_get(THIS_MODULE);
> +
> + return 0;
> +err_name:
> + ida_simple_remove(&vduse_ida, dev->minor);
> +err_ida:
> + kfree(dev->vqs);
> +err_vqs:
> + vduse_domain_destroy(dev->domain);
> +err_domain:
> + vduse_dev_destroy(dev);
> + return ret;
> +}
> +
> +static long vduse_ioctl(struct file *file, unsigned int cmd,
> + unsigned long arg)
> +{
> + int ret;
> + void __user *argp = (void __user *)arg;
> +
> + mutex_lock(&vduse_lock);
> + switch (cmd) {
> + case VDUSE_CREATE_DEV: {
> + struct vduse_dev_config config;
> +
> + ret = -EFAULT;
> + if (copy_from_user(&config, argp, sizeof(config)))
> + break;
> +
> + ret = vduse_create_dev(&config);
> + break;
> + }
> + case VDUSE_DESTROY_DEV: {
> + char name[VDUSE_NAME_MAX];
> +
> + ret = -EFAULT;
> + if (copy_from_user(name, argp, VDUSE_NAME_MAX))
> + break;
> +
> + ret = vduse_destroy_dev(name);
> + break;
> + }
> + default:
> + ret = -EINVAL;
> + break;
> + }
> + mutex_unlock(&vduse_lock);
> +
> + return ret;
> +}
> +
> +static const struct file_operations vduse_fops = {
> + .owner = THIS_MODULE,
> + .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 struct miscdevice vduse_misc = {
> + .fops = &vduse_fops,
> + .minor = MISC_DYNAMIC_MINOR,
> + .name = "vduse",
> + .nodename = "vduse/control",
> +};
> +
> +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_add_vdpa(struct vduse_dev *dev, const char *name)
> +{
> + struct vduse_vdpa *vdev = dev->vdev;
> + int ret;
> +
> + if (vdev)
> + return -EEXIST;
> +
> + vdev = vdpa_alloc_device(struct vduse_vdpa, vdpa, NULL,
I think the char dev should be used as the parent here.
> + &vduse_vdpa_config_ops,
> + dev->vq_num, name, true);
> + if (!vdev)
> + return -ENOMEM;
> +
> + 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)
> + goto err;
> +
> + set_dma_ops(&vdev->vdpa.dev, &vduse_dev_dma_ops);
> + vdev->vdpa.dma_dev = &vdev->vdpa.dev;
> + vdev->vdpa.mdev = &mgmt_dev;
> +
> + ret = _vdpa_register_device(&vdev->vdpa);
> + if (ret)
> + goto err;
> +
> + dev->vdev = vdev;
> +
> + return 0;
> +err:
> + put_device(&vdev->vdpa.dev);
> + return ret;
> +}
> +
> +static int vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name)
> +{
> + struct vduse_dev *dev;
> + int ret = -EINVAL;
> +
> + mutex_lock(&vduse_lock);
> + dev = vduse_find_dev(name);
> + if (!dev)
> + goto unlock;
Any reason for this check? I think vdpa core layer has already did for
the name check for us.
> +
> + ret = vduse_dev_add_vdpa(dev, name);
> +unlock:
> + mutex_unlock(&vduse_lock);
> +
> + return ret;
> +}
> +
> +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_DEV_ANY_ID, 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;
> +
> + ret = misc_register(&vduse_misc);
> + if (ret)
> + return ret;
> +
> + vduse_class = class_create(THIS_MODULE, "vduse");
> + if (IS_ERR(vduse_class)) {
> + ret = PTR_ERR(vduse_class);
> + goto err_class;
> + }
> + vduse_class->devnode = vduse_devnode;
> +
> + ret = alloc_chrdev_region(&vduse_major, 0, VDUSE_DEV_MAX, "vduse");
> + if (ret)
> + goto err_chardev;
> +
> + ret = vduse_domain_init();
> + if (ret)
> + goto err_domain;
> +
> + ret = vduse_mgmtdev_init();
> + if (ret)
> + goto err_mgmtdev;
Should we validate max_bounce_size < max_iova_size here?
Thanks
> +
> + return 0;
> +err_mgmtdev:
> + vduse_domain_exit();
> +err_domain:
> + unregister_chrdev_region(vduse_major, VDUSE_DEV_MAX);
> +err_chardev:
> + class_destroy(vduse_class);
> +err_class:
> + misc_deregister(&vduse_misc);
> + return ret;
> +}
> +module_init(vduse_init);
> +
> +static void vduse_exit(void)
> +{
> + misc_deregister(&vduse_misc);
> + class_destroy(vduse_class);
> + unregister_chrdev_region(vduse_major, VDUSE_DEV_MAX);
> + vduse_domain_exit();
> + vduse_mgmtdev_exit();
> +}
> +module_exit(vduse_exit);
> +
> +MODULE_VERSION(DRV_VERSION);
> +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 000000000000..9391c4acfa53
> --- /dev/null
> +++ b/include/uapi/linux/vduse.h
> @@ -0,0 +1,136 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +#ifndef _UAPI_VDUSE_H_
> +#define _UAPI_VDUSE_H_
> +
> +#include <linux/types.h>
> +
> +#define VDUSE_CONFIG_DATA_LEN 256
> +#define VDUSE_NAME_MAX 256
> +
> +/* the control messages definition for read/write */
> +
> +enum vduse_req_type {
> + VDUSE_SET_VQ_NUM,
> + VDUSE_SET_VQ_ADDR,
> + VDUSE_SET_VQ_READY,
> + VDUSE_GET_VQ_READY,
> + VDUSE_SET_VQ_STATE,
> + VDUSE_GET_VQ_STATE,
> + VDUSE_SET_FEATURES,
> + VDUSE_GET_FEATURES,
> + VDUSE_SET_STATUS,
> + VDUSE_GET_STATUS,
> + VDUSE_SET_CONFIG,
> + VDUSE_GET_CONFIG,
> + VDUSE_UPDATE_IOTLB,
> +};
> +
> +struct vduse_vq_num {
> + __u32 index;
> + __u32 num;
> +};
> +
> +struct vduse_vq_addr {
> + __u32 index;
> + __u64 desc_addr;
> + __u64 driver_addr;
> + __u64 device_addr;
> +};
> +
> +struct vduse_vq_ready {
> + __u32 index;
> + __u8 ready;
> +};
> +
> +struct vduse_vq_state {
> + __u32 index;
> + __u16 avail_idx;
> +};
> +
> +struct vduse_dev_config_data {
> + __u32 offset;
> + __u32 len;
> + __u8 data[VDUSE_CONFIG_DATA_LEN];
> +};
> +
> +struct vduse_iova_range {
> + __u64 start;
> + __u64 last;
> +};
> +
> +struct vduse_dev_request {
> + __u32 type; /* request type */
> + __u32 unique; /* request id */
Let's simply use "request_id" here.
> + __u32 reserved[2]; /* for feature use */
> + union {
> + struct vduse_vq_num vq_num; /* virtqueue num */
> + struct vduse_vq_addr vq_addr; /* virtqueue address */
> + struct vduse_vq_ready vq_ready; /* virtqueue ready status */
> + struct vduse_vq_state vq_state; /* virtqueue state */
> + struct vduse_dev_config_data config; /* virtio device config space */
> + struct vduse_iova_range iova; /* iova range for updating */
> + __u64 features; /* virtio features */
> + __u8 status; /* device status */
It might be better to use struct for feaures and status as well for
consistency.
And to be safe, let's add explicity padding here.
> + };
> +};
> +
> +struct vduse_dev_response {
> + __u32 request_id; /* corresponding request id */
> +#define VDUSE_REQUEST_OK 0x00
> +#define VDUSE_REQUEST_FAILED 0x01
> + __u8 result; /* the result of request */
> + __u8 reserved[11]; /* for feature use */
Looks like this will be a hole which is similar to
429711aec282c4b5fe5bbd7b2f0bbbff4110ffb2. Need to make sure the reserved
end at 8 byte boundary.
> + union {
> + struct vduse_vq_ready vq_ready; /* virtqueue ready status */
> + struct vduse_vq_state vq_state; /* virtqueue state */
> + struct vduse_dev_config_data config; /* virtio device config space */
> + __u64 features; /* virtio features */
> + __u8 status; /* device status */
> + };
> +};
> +
> +/* ioctls */
> +
> +struct vduse_dev_config {
> + char name[VDUSE_NAME_MAX]; /* vduse device name */
> + __u32 vendor_id; /* virtio vendor id */
> + __u32 device_id; /* virtio device id */
> + __u64 bounce_size; /* bounce buffer size for iommu */
> + __u16 vq_num; /* the number of virtqueues */
> + __u16 vq_size_max; /* the max size of virtqueue */
> + __u32 vq_align; /* the allocation alignment of virtqueue's metadata */
> +};
> +
> +struct vduse_iotlb_entry {
> + __u64 offset; /* the mmap offset on fd */
> + __u64 start; /* start of the IOVA range */
> + __u64 last; /* last of the IOVA range */
> +#define VDUSE_ACCESS_RO 0x1
> +#define VDUSE_ACCESS_WO 0x2
> +#define VDUSE_ACCESS_RW 0x3
> + __u8 perm; /* access permission of this range */
> +};
> +
> +struct vduse_vq_eventfd {
> + __u32 index; /* virtqueue index */
> + int fd; /* eventfd, -1 means de-assigning the eventfd */
Let's define a macro for this.
> +};
> +
> +#define VDUSE_BASE 0x81
> +
> +/* Create a vduse device which is represented by a char device (/dev/vduse/<name>) */
> +#define VDUSE_CREATE_DEV _IOW(VDUSE_BASE, 0x01, struct vduse_dev_config)
> +
> +/* Destroy a vduse device. Make sure there are no references to the char device */
> +#define VDUSE_DESTROY_DEV _IOW(VDUSE_BASE, 0x02, char[VDUSE_NAME_MAX])
> +
> +/* Get a file descriptor for the mmap'able iova region */
> +#define VDUSE_IOTLB_GET_FD _IOWR(VDUSE_BASE, 0x03, struct vduse_iotlb_entry)
> +
> +/* Setup an eventfd to receive kick for virtqueue */
> +#define VDUSE_VQ_SETUP_KICKFD _IOW(VDUSE_BASE, 0x04, struct vduse_vq_eventfd)
> +
> +/* Inject an interrupt for specific virtqueue */
> +#define VDUSE_INJECT_VQ_IRQ _IO(VDUSE_BASE, 0x05)
I wonder do we need a version/feature handshake that is for future
extension instead of just reserve bits in uABI? E.g VDUSE_GET_VERSION ...
Thanks
> +
> +#endif /* _UAPI_VDUSE_H_ */
next prev parent reply other threads:[~2021-03-04 6:29 UTC|newest]
Thread overview: 65+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-23 11:50 [RFC v4 00/11] Introduce VDUSE - vDPA Device in Userspace Xie Yongji
2021-02-23 11:50 ` [RFC v4 01/11] eventfd: Increase the recursion depth of eventfd_signal() Xie Yongji
2021-03-02 6:44 ` Jason Wang
2021-03-02 10:32 ` Yongji Xie
2021-02-23 11:50 ` [RFC v4 02/11] vhost-vdpa: protect concurrent access to vhost device iotlb Xie Yongji
2021-03-02 6:47 ` Jason Wang
2021-03-02 10:20 ` Yongji Xie
2021-02-23 11:50 ` [RFC v4 03/11] vhost-iotlb: Add an opaque pointer for vhost IOTLB Xie Yongji
2021-03-02 6:49 ` Jason Wang
2021-02-23 11:50 ` [RFC v4 04/11] vdpa: Add an opaque pointer for vdpa_config_ops.dma_map() Xie Yongji
2021-03-02 6:50 ` Jason Wang
2021-02-23 11:50 ` [RFC v4 05/11] vdpa: Support transferring virtual addressing during DMA mapping Xie Yongji
2021-03-03 10:52 ` Mika Penttilä
2021-03-03 12:45 ` Yongji Xie
2021-03-03 13:38 ` Mika Penttilä
2021-03-04 3:07 ` Jason Wang
2021-03-04 5:40 ` Yongji Xie
2021-02-23 11:50 ` [RFC v4 06/11] vduse: Implement an MMU-based IOMMU driver Xie Yongji
2021-03-04 4:20 ` Jason Wang
2021-03-04 5:12 ` Yongji Xie
2021-03-05 3:35 ` Jason Wang
2021-03-05 6:15 ` Yongji Xie
[not found] ` <4db35f8c-ee3a-90fb-8d14-5d6014b4f6fa@redhat.com>
2021-03-05 7:13 ` Yongji Xie
2021-03-05 7:27 ` Jason Wang
2021-03-05 7:59 ` Yongji Xie
2021-03-08 3:17 ` Jason Wang
2021-03-08 3:45 ` Yongji Xie
2021-03-08 3:52 ` Jason Wang
2021-03-08 5:05 ` Yongji Xie
2021-03-08 7:04 ` Jason Wang
2021-03-08 7:08 ` Yongji Xie
2021-02-23 11:50 ` [RFC v4 07/11] vduse: Introduce VDUSE - vDPA Device in Userspace Xie Yongji
2021-03-04 6:27 ` Jason Wang [this message]
2021-03-04 8:05 ` Yongji Xie
2021-03-05 3:20 ` Jason Wang
2021-03-05 3:49 ` Yongji Xie
2021-03-10 12:58 ` Jason Wang
2021-03-11 2:28 ` Yongji Xie
2021-02-23 11:50 ` [RFC v4 08/11] vduse: Add config interrupt support Xie Yongji
2021-02-23 11:50 ` [RFC v4 09/11] Documentation: Add documentation for VDUSE Xie Yongji
2021-03-04 6:39 ` Jason Wang
2021-03-04 10:35 ` Yongji Xie
2021-02-23 11:50 ` [RFC v4 10/11] vduse: Introduce a workqueue for irq injection Xie Yongji
2021-03-04 6:59 ` Jason Wang
2021-03-04 8:58 ` Yongji Xie
2021-03-05 3:04 ` Jason Wang
2021-03-05 3:30 ` Yongji Xie
2021-03-05 3:42 ` Jason Wang
2021-03-05 6:36 ` Yongji Xie
2021-03-05 7:01 ` Jason Wang
2021-03-05 7:27 ` Yongji Xie
2021-03-05 7:36 ` Jason Wang
2021-03-05 8:12 ` Yongji Xie
2021-03-08 3:04 ` Jason Wang
2021-03-08 4:50 ` Yongji Xie
2021-03-08 7:01 ` Jason Wang
2021-03-08 7:16 ` Yongji Xie
2021-03-08 7:29 ` Jason Wang
2021-02-23 11:50 ` [RFC v4 11/11] vduse: Support binding irq to the specified cpu Xie Yongji
2021-03-04 7:30 ` Jason Wang
2021-03-04 8:19 ` Yongji Xie
2021-03-05 3:11 ` Jason Wang
2021-03-05 3:37 ` Yongji Xie
2021-03-05 3:44 ` Jason Wang
2021-03-05 6:40 ` Yongji Xie
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