On Tue, Sep 12, 2023 at 11:00 AM Cindy Lu <lulu@xxxxxxxxxx> wrote:
>
> In VDUSE_VQ_GET_INFO, the driver will sync the last_avail_idx
> with reconnect info, After mapping the reconnect pages to userspace
> The userspace App will update the reconnect_time in
> struct vhost_reconnect_vring, If this is not 0 then it means this
> vq is reconnected and will update the last_avail_idx
>
> Signed-off-by: Cindy Lu <lulu@xxxxxxxxxx>
> ---
> drivers/vdpa/vdpa_user/vduse_dev.c | 13 +++++++++++++
> include/uapi/linux/vduse.h | 6 ++++++
> 2 files changed, 19 insertions(+)
>
> diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
> index 2c69f4004a6e..680b23dbdde2 100644
> --- a/drivers/vdpa/vdpa_user/vduse_dev.c
> +++ b/drivers/vdpa/vdpa_user/vduse_dev.c
> @@ -1221,6 +1221,8 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
> struct vduse_vq_info vq_info;
> struct vduse_virtqueue *vq;
> u32 index;
> + struct vdpa_reconnect_info *area;
> + struct vhost_reconnect_vring *vq_reconnect;
>
> ret = -EFAULT;
> if (copy_from_user(&vq_info, argp, sizeof(vq_info)))
> @@ -1252,6 +1254,17 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
>
> vq_info.ready = vq->ready;
>
> + area = &vq->reconnect_info;
> +
> + vq_reconnect = (struct vhost_reconnect_vring *)area->vaddr;
> + /*check if the vq is reconnect, if yes then update the last_avail_idx*/
> + if ((vq_reconnect->last_avail_idx !=
> + vq_info.split.avail_index) &&
> + (vq_reconnect->reconnect_time != 0)) {
> + vq_info.split.avail_index =
> + vq_reconnect->last_avail_idx;
> + }
> +
> ret = -EFAULT;
> if (copy_to_user(argp, &vq_info, sizeof(vq_info)))
> break;
> diff --git a/include/uapi/linux/vduse.h b/include/uapi/linux/vduse.h
> index 11bd48c72c6c..d585425803fd 100644
> --- a/include/uapi/linux/vduse.h
> +++ b/include/uapi/linux/vduse.h
> @@ -350,4 +350,10 @@ struct vduse_dev_response {
> };
> };
>
> +struct vhost_reconnect_vring {
> + __u16 reconnect_time;
> + __u16 last_avail_idx;
> + _Bool avail_wrap_counter;
Please add a comment for each field.
And I never saw _Bool is used in uapi before, maybe it's better to
pack it with last_avail_idx into a __u32.
Btw, do we need to track inflight descriptors as well?
Thanks
> +};
> +
> #endif /* _UAPI_VDUSE_H_ */
> --
> 2.34.3
>
