Re: [PATCH v12 24/40] virtio: allow to unbreak/break virtqueue individually

Jason Wang
2022-07-21T09:14:29Z

在 2022/7/20 11:04, Xuan Zhuo 写道:
> This patch allows the new introduced
> __virtqueue_break()/__virtqueue_unbreak() to break/unbreak the
> virtqueue.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>

Acked-by: Jason Wang <jasowang@redhat.com>

> ---
> drivers/virtio/virtio_ring.c | 24 ++++++++++++++++++++++++
> include/linux/virtio.h | 3 +++
> 2 files changed, 27 insertions(+)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index cf4379175163..bf666dad9904 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -2730,6 +2730,30 @@ unsigned int virtqueue_get_vring_size(struct virtqueue *_vq)
> }
> EXPORT_SYMBOL_GPL(virtqueue_get_vring_size);
>
> +/*
> + * This function should only be called by the core, not directly by the driver.
> + */
> +void __virtqueue_break(struct virtqueue *_vq)
> +{
> + struct vring_virtqueue *vq = to_vvq(_vq);
> +
> + /* Pairs with READ_ONCE() in virtqueue_is_broken(). */
> + WRITE_ONCE(vq->broken, true);
> +}
> +EXPORT_SYMBOL_GPL(__virtqueue_break);
> +
> +/*
> + * This function should only be called by the core, not directly by the driver.
> + */
> +void __virtqueue_unbreak(struct virtqueue *_vq)
> +{
> + struct vring_virtqueue *vq = to_vvq(_vq);
> +
> + /* Pairs with READ_ONCE() in virtqueue_is_broken(). */
> + WRITE_ONCE(vq->broken, false);
> +}
> +EXPORT_SYMBOL_GPL(__virtqueue_unbreak);
> +
> bool virtqueue_is_broken(struct virtqueue *_vq)
> {
> struct vring_virtqueue *vq = to_vvq(_vq);
> diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> index 62e31bca5602..d45ee82a4470 100644
> --- a/include/linux/virtio.h
> +++ b/include/linux/virtio.h
> @@ -138,6 +138,9 @@ bool is_virtio_device(struct device *dev);
> void virtio_break_device(struct virtio_device *dev);
> void __virtio_unbreak_device(struct virtio_device *dev);
>
> +void __virtqueue_break(struct virtqueue *_vq);
> +void __virtqueue_unbreak(struct virtqueue *_vq);
> +
> void virtio_config_changed(struct virtio_device *dev);
> #ifdef CONFIG_PM_SLEEP
> int virtio_device_freeze(struct virtio_device *dev);