Commit 2c4e4a22 authored by Alvaro Karsz's avatar Alvaro Karsz Committed by Michael S. Tsirkin
Browse files

virtio-vdpa: add VIRTIO_F_NOTIFICATION_DATA feature support 



Add VIRTIO_F_NOTIFICATION_DATA support for vDPA transport.
If this feature is negotiated, the driver passes extra data when kicking
a virtqueue.

A device that offers this feature needs to implement the
kick_vq_with_data callback.

kick_vq_with_data receives the vDPA device and data.
data includes:
16 bits vqn and 16 bits next available index for split virtqueues.
16 bits vqs, 15 least significant bits of next available index
and 1 bit next_wrap for packed virtqueues.

This patch follows a patch [1] by Viktor Prutyanov which adds support
for the MMIO, channel I/O and modern PCI transports.

Signed-off-by: default avatarAlvaro Karsz <alvaro.karsz@solid-run.com>
Message-Id: <20230413081855.36643-3-alvaro.karsz@solid-run.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Acked-by: default avatarJason Wang <jasowang@redhat.com>
parent af8ececd

drivers/virtio/virtio_vdpa.c

+21 −2
Original line number Diff line number Diff line
@@ -113,6 +113,17 @@ static bool virtio_vdpa_notify(struct virtqueue *vq) 
	return true;

}



static bool virtio_vdpa_notify_with_data(struct virtqueue *vq)

{

	struct vdpa_device *vdpa = vd_get_vdpa(vq->vdev);

	const struct vdpa_config_ops *ops = vdpa->config;

	u32 data = vring_notification_data(vq);



	ops->kick_vq_with_data(vdpa, data);



	return true;

}



static irqreturn_t virtio_vdpa_config_cb(void *private)

{

	struct virtio_vdpa_device *vd_dev = private;
@@ -139,6 +150,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index, 
	struct device *dma_dev;

	const struct vdpa_config_ops *ops = vdpa->config;

	struct virtio_vdpa_vq_info *info;

	bool (*notify)(struct virtqueue *vq) = virtio_vdpa_notify;

	struct vdpa_callback cb;

	struct virtqueue *vq;

	u64 desc_addr, driver_addr, device_addr;
@@ -155,6 +167,14 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index, 
	if (index >= vdpa->nvqs)

		return ERR_PTR(-ENOENT);



	/* We cannot accept VIRTIO_F_NOTIFICATION_DATA without kick_vq_with_data */

	if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA)) {

		if (ops->kick_vq_with_data)

			notify = virtio_vdpa_notify_with_data;

		else

			__virtio_clear_bit(vdev, VIRTIO_F_NOTIFICATION_DATA);

	}



	/* Queue shouldn't already be set up. */

	if (ops->get_vq_ready(vdpa, index))

		return ERR_PTR(-ENOENT);
@@ -184,8 +204,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index, 
		dma_dev = vdpa_get_dma_dev(vdpa);

	vq = vring_create_virtqueue_dma(index, max_num, align, vdev,

					true, may_reduce_num, ctx,

					virtio_vdpa_notify, callback,

					name, dma_dev);

					notify, callback, name, dma_dev);

	if (!vq) {

		err = -ENOMEM;

		goto error_new_virtqueue;

include/linux/vdpa.h

+9 −0
Original line number Diff line number Diff line
@@ -149,6 +149,14 @@ struct vdpa_map_file { 
 * @kick_vq:			Kick the virtqueue

 *				@vdev: vdpa device

 *				@idx: virtqueue index

 * @kick_vq_with_data:		Kick the virtqueue and supply extra data

 *				(only if VIRTIO_F_NOTIFICATION_DATA is negotiated)

 *				@vdev: vdpa device

 *				@data for split virtqueue:

 *				16 bits vqn and 16 bits next available index.

 *				@data for packed virtqueue:

 *				16 bits vqn, 15 least significant bits of

 *				next available index and 1 bit next_wrap.

 * @set_vq_cb:			Set the interrupt callback function for

 *				a virtqueue

 *				@vdev: vdpa device
@@ -329,6 +337,7 @@ struct vdpa_config_ops { 
			      u64 device_area);

	void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num);

	void (*kick_vq)(struct vdpa_device *vdev, u16 idx);

	void (*kick_vq_with_data)(struct vdpa_device *vdev, u32 data);

	void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx,

			  struct vdpa_callback *cb);

	void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready);