Re: [PATCH v2 2/5] virtio-mmio: refactor common functionality

["Michael S. Tsirkin" <mst@redhat.com>]

On Mon, Feb 10, 2020 at 05:05:18PM +0800, Zha Bin wrote:
> From: Liu Jiang <gerry@linux.alibaba.com>
> 
> Common functionality is refactored into virtio_mmio_common.h
> in order to MSI support in later patch set.
> 
> Signed-off-by: Liu Jiang <gerry@linux.alibaba.com>
> Co-developed-by: Zha Bin <zhabin@linux.alibaba.com>
> Signed-off-by: Zha Bin <zhabin@linux.alibaba.com>
> Co-developed-by: Jing Liu <jing2.liu@linux.intel.com>
> Signed-off-by: Jing Liu <jing2.liu@linux.intel.com>
> Co-developed-by: Chao Peng <chao.p.peng@linux.intel.com>
> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>

What does this proliferation of header files achieve?
common with what?

> ---
>  drivers/virtio/virtio_mmio.c        | 21 +--------------------
>  drivers/virtio/virtio_mmio_common.h | 31 +++++++++++++++++++++++++++++++
>  2 files changed, 32 insertions(+), 20 deletions(-)
>  create mode 100644 drivers/virtio/virtio_mmio_common.h
> 
> diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
> index 1733ab97..41e1c93 100644
> --- a/drivers/virtio/virtio_mmio.c
> +++ b/drivers/virtio/virtio_mmio.c
> @@ -61,13 +61,12 @@
>  #include <linux/io.h>
>  #include <linux/list.h>
>  #include <linux/module.h>
> -#include <linux/platform_device.h>
>  #include <linux/slab.h>
>  #include <linux/spinlock.h>
> -#include <linux/virtio.h>
>  #include <linux/virtio_config.h>
>  #include <uapi/linux/virtio_mmio.h>
>  #include <linux/virtio_ring.h>
> +#include "virtio_mmio_common.h"
>  
>  
>  
> @@ -77,24 +76,6 @@
>  
>  
>  
> -#define to_virtio_mmio_device(_plat_dev) \
> -	container_of(_plat_dev, struct virtio_mmio_device, vdev)
> -
> -struct virtio_mmio_device {
> -	struct virtio_device vdev;
> -	struct platform_device *pdev;
> -
> -	void __iomem *base;
> -	unsigned long version;
> -
> -	/* a list of queues so we can dispatch IRQs */
> -	spinlock_t lock;
> -	struct list_head virtqueues;
> -
> -	unsigned short notify_base;
> -	unsigned short notify_multiplier;
> -};
> -
>  struct virtio_mmio_vq_info {
>  	/* the actual virtqueue */
>  	struct virtqueue *vq;
> diff --git a/drivers/virtio/virtio_mmio_common.h b/drivers/virtio/virtio_mmio_common.h
> new file mode 100644
> index 0000000..90cb304
> --- /dev/null
> +++ b/drivers/virtio/virtio_mmio_common.h
> @@ -0,0 +1,31 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +#ifndef _DRIVERS_VIRTIO_VIRTIO_MMIO_COMMON_H
> +#define _DRIVERS_VIRTIO_VIRTIO_MMIO_COMMON_H
> +/*
> + * Virtio MMIO driver - common functionality for all device versions
> + *
> + * This module allows virtio devices to be used over a memory-mapped device.
> + */
> +
> +#include <linux/platform_device.h>
> +#include <linux/virtio.h>
> +
> +#define to_virtio_mmio_device(_plat_dev) \
> +	container_of(_plat_dev, struct virtio_mmio_device, vdev)
> +
> +struct virtio_mmio_device {
> +	struct virtio_device vdev;
> +	struct platform_device *pdev;
> +
> +	void __iomem *base;
> +	unsigned long version;
> +
> +	/* a list of queues so we can dispatch IRQs */
> +	spinlock_t lock;
> +	struct list_head virtqueues;
> +
> +	unsigned short notify_base;
> +	unsigned short notify_multiplier;
> +};
> +
> +#endif
> -- 
> 1.8.3.1