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. This patch needs to be applied on top of Viktor's patch. [1] https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Alvaro Karsz <[email protected]> --- v2: - clear the feature bit if kick_vq_with_data is not implemented. - Fix kick_vq_with_data comment in include/linux/vdpa.h - Write in more detail about the extra data in the commit log drivers/virtio/virtio_vdpa.c | 23 +++++++++++++++++++++-- include/linux/vdpa.h | 9 +++++++++ 2 files changed, 30 insertions(+), 2 deletions(-) diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c index d7f5af62dda..737c1f36d32 100644 --- a/drivers/virtio/virtio_vdpa.c +++ b/drivers/virtio/virtio_vdpa.c @@ -112,6 +112,17 @@ 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; @@ -138,6 +149,7 @@ 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; @@ -154,6 +166,14 @@ 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); @@ -183,8 +203,7 @@ 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; diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h index 43f59ef10cc..04cdaad77dd 100644 --- a/include/linux/vdpa.h +++ b/include/linux/vdpa.h @@ -143,6 +143,14 @@ 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 @@ -300,6 +308,7 @@ 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); -- 2.34.1 _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
