[PATCH v11 28/40] virtio_pci: introduce helper to get/set queue reset

[Jason Wang]

在 2022/6/29 14:56, Xuan Zhuo 写道:
> Introduce new helpers to implement queue reset and get queue reset
> status.
>
>   https://github.com/oasis-tcs/virtio-spec/issues/124
>   https://github.com/oasis-tcs/virtio-spec/issues/139
>
> Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>


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


> ---
>   drivers/virtio/virtio_pci_modern_dev.c | 35 ++++++++++++++++++++++++++
>   include/linux/virtio_pci_modern.h      |  2 ++
>   2 files changed, 37 insertions(+)
>
> diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c
> index fa2a9445bb18..07415654247c 100644
> --- a/drivers/virtio/virtio_pci_modern_dev.c
> +++ b/drivers/virtio/virtio_pci_modern_dev.c
> @@ -3,6 +3,7 @@
>   #include <linux/virtio_pci_modern.h>
>   #include <linux/module.h>
>   #include <linux/pci.h>
> +#include <linux/delay.h>
>   
>   /*
>    * vp_modern_map_capability - map a part of virtio pci capability
> @@ -474,6 +475,40 @@ void vp_modern_set_status(struct virtio_pci_modern_device *mdev,
>   }
>   EXPORT_SYMBOL_GPL(vp_modern_set_status);
>   
> +/*
> + * vp_modern_get_queue_reset - get the queue reset status
> + * @mdev: the modern virtio-pci device
> + * @index: queue index
> + */
> +int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index)
> +{
> +	struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
> +
> +	vp_iowrite16(index, &cfg->queue_select);
> +	return vp_ioread16(&cfg->queue_reset);
> +}
> +EXPORT_SYMBOL_GPL(vp_modern_get_queue_reset);
> +
> +/*
> + * vp_modern_set_queue_reset - reset the queue
> + * @mdev: the modern virtio-pci device
> + * @index: queue index
> + */
> +void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index)
> +{
> +	struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
> +
> +	vp_iowrite16(index, &cfg->queue_select);
> +	vp_iowrite16(1, &cfg->queue_reset);
> +
> +	while (vp_ioread16(&cfg->queue_reset))
> +		msleep(1);
> +
> +	while (vp_ioread16(&cfg->queue_enable))
> +		msleep(1);
> +}
> +EXPORT_SYMBOL_GPL(vp_modern_set_queue_reset);
> +
>   /*
>    * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue
>    * @mdev: the modern virtio-pci device
> diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h
> index beebc7a4a31d..ded01157f864 100644
> --- a/include/linux/virtio_pci_modern.h
> +++ b/include/linux/virtio_pci_modern.h
> @@ -134,4 +134,6 @@ void __iomem * vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
>   				       u16 index, resource_size_t *pa);
>   int vp_modern_probe(struct virtio_pci_modern_device *mdev);
>   void vp_modern_remove(struct virtio_pci_modern_device *mdev);
> +int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index);
> +void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index);
>   #endif