On Fri, May 20, 2022 at 07:23:24PM +0200, Eugenio Pérez wrote:
> The ioctl adds support for stop the device from userspace.
>
> Signed-off-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
> ---
> drivers/vhost/vdpa.c | 18 ++++++++++++++++++
> include/uapi/linux/vhost.h | 3 +++
> 2 files changed, 21 insertions(+)
>
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index a325bc259afb..da4a8c709bc1 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -478,6 +478,21 @@ static long vhost_vdpa_get_vqs_count(struct vhost_vdpa *v, u32 __user *argp)
> return 0;
> }
>
> +static long vhost_vdpa_stop(struct vhost_vdpa *v, u32 __user *argp)
> +{
> + struct vdpa_device *vdpa = v->vdpa;
> + const struct vdpa_config_ops *ops = vdpa->config;
> + int stop;
> +
> + if (!ops->stop)
> + return -EOPNOTSUPP;
> +
> + if (copy_to_user(argp, &stop, sizeof(stop)))
You want to use copy_from_user() here.
Martin
> + return -EFAULT;
> +
> + return ops->stop(vdpa, stop);
> +}
> +
> static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
> void __user *argp)
> {
> @@ -649,6 +664,9 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
> case VHOST_VDPA_GET_VQS_COUNT:
> r = vhost_vdpa_get_vqs_count(v, argp);
> break;
> + case VHOST_STOP:
> + r = vhost_vdpa_stop(v, argp);
> + break;
> default:
> r = vhost_dev_ioctl(&v->vdev, cmd, argp);
> if (r == -ENOIOCTLCMD)
> diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
> index cab645d4a645..e7526968ab0c 100644
> --- a/include/uapi/linux/vhost.h
> +++ b/include/uapi/linux/vhost.h
> @@ -171,4 +171,7 @@
> #define VHOST_VDPA_SET_GROUP_ASID _IOW(VHOST_VIRTIO, 0x7C, \
> struct vhost_vring_state)
>
> +/* Stop or resume a device so it does not process virtqueue requests anymore */
> +#define VHOST_STOP _IOW(VHOST_VIRTIO, 0x7D, int)
> +
> #endif
> --
> 2.27.0
