Re: [Qemu-devel] [PATCH v2 1/2] virtio: introduce little edian functions for virtio_cread/write# family

[Michael S. Tsirkin]

On Tue, Nov 22, 2016 at 04:10:22PM +0800, Gonglei wrote:
> Virtio modern devices are always little edian, let's introduce
> the LE functions for read/write configuration space for
> virtio modern devices, which avoid complaint by Sparse when
> we use the virtio_creaed/virtio_cwrite in VIRTIO_1 devices.
> 
> Signed-off-by: Gonglei <address@hidden>
> ---
>  include/linux/virtio_config.h | 45 
> +++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 45 insertions(+)
> 
> diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
> index 26c155b..de05707 100644
> --- a/include/linux/virtio_config.h
> +++ b/include/linux/virtio_config.h
> @@ -414,4 +414,49 @@ static inline void virtio_cwrite64(struct virtio_device 
> *vdev,
>               _r;                                                     \
>       })
>  
> +static inline __le16 virtio_cread16_le(struct virtio_device *vdev,
> +                              unsigned int offset)
> +{
> +     __le16 ret;
> +
> +     vdev->config->get(vdev, offset, &ret, sizeof(ret));
> +     return ret;
> +}
> +
> +static inline void virtio_cwrite16_le(struct virtio_device *vdev,
> +                                unsigned int offset, __le16 val)
> +{
> +     vdev->config->set(vdev, offset, &val, sizeof(val));
> +}
> +
> +static inline __le32 virtio_cread32_le(struct virtio_device *vdev,
> +                              unsigned int offset)
> +{
> +     __le32 ret;
> +
> +     vdev->config->get(vdev, offset, &ret, sizeof(ret));
> +     return ret;
> +}
> +
> +static inline void virtio_cwrite32_le(struct virtio_device *vdev,
> +                                unsigned int offset, __le32 val)
> +{
> +     vdev->config->set(vdev, offset, &val, sizeof(val));
> +}
> +
> +static inline __le64 virtio_cread64_le(struct virtio_device *vdev,
> +                              unsigned int offset)
> +{
> +     __le64 ret;
> +
> +     __virtio_cread_many(vdev, offset, &ret, 1, sizeof(ret));
> +     return ret;
> +}
> +
> +static inline void virtio_cwrite64_le(struct virtio_device *vdev,
> +                                unsigned int offset, __le64 val)
> +{
> +     vdev->config->set(vdev, offset, &val, sizeof(val));
> +}
> +
>  #endif /* _LINUX_VIRTIO_CONFIG_H */

Could you please better explain what is the issue you are facing?
virtio_cwrite/virtio_cread all accept and return native types.

If you want it in LE format, swap it!



> -- 
> 1.8.3.1
>