On Wed, Jun 29, 2022 at 2:57 PM Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> wrote:
>
> Record the maximum queue num supported by the device.
>
> virtio-net can display the maximum (supported by hardware) ring size in
> ethtool -g eth0.
>
> When the subsequent patch implements vring reset, it can judge whether
> the ring size passed by the driver is legal based on this.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
> ---
> arch/um/drivers/virtio_uml.c | 1 +
> drivers/platform/mellanox/mlxbf-tmfifo.c | 2 ++
> drivers/remoteproc/remoteproc_virtio.c | 2 ++
> drivers/s390/virtio/virtio_ccw.c | 3 +++
> drivers/virtio/virtio_mmio.c | 2 ++
> drivers/virtio/virtio_pci_legacy.c | 2 ++
> drivers/virtio/virtio_pci_modern.c | 2 ++
> drivers/virtio/virtio_ring.c | 14 ++++++++++++++
> drivers/virtio/virtio_vdpa.c | 2 ++
> include/linux/virtio.h | 2 ++
> 10 files changed, 32 insertions(+)
>
> diff --git a/arch/um/drivers/virtio_uml.c b/arch/um/drivers/virtio_uml.c
> index 82ff3785bf69..e719af8bdf56 100644
> --- a/arch/um/drivers/virtio_uml.c
> +++ b/arch/um/drivers/virtio_uml.c
> @@ -958,6 +958,7 @@ static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
> goto error_create;
> }
> vq->priv = info;
> + vq->num_max = num;
> num = virtqueue_get_vring_size(vq);
>
> if (vu_dev->protocol_features &
> diff --git a/drivers/platform/mellanox/mlxbf-tmfifo.c b/drivers/platform/mellanox/mlxbf-tmfifo.c
> index 38800e86ed8a..1ae3c56b66b0 100644
> --- a/drivers/platform/mellanox/mlxbf-tmfifo.c
> +++ b/drivers/platform/mellanox/mlxbf-tmfifo.c
> @@ -959,6 +959,8 @@ static int mlxbf_tmfifo_virtio_find_vqs(struct virtio_device *vdev,
> goto error;
> }
>
> + vq->num_max = vring->num;
> +
> vqs[i] = vq;
> vring->vq = vq;
> vq->priv = vring;
> diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c
> index d43d74733f0a..0f7706e23eb9 100644
> --- a/drivers/remoteproc/remoteproc_virtio.c
> +++ b/drivers/remoteproc/remoteproc_virtio.c
> @@ -125,6 +125,8 @@ static struct virtqueue *rp_find_vq(struct virtio_device *vdev,
> return ERR_PTR(-ENOMEM);
> }
>
> + vq->num_max = num;
> +
> rvring->vq = vq;
> vq->priv = rvring;
>
> diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
> index 161d3b141f0d..6b86d0280d6b 100644
> --- a/drivers/s390/virtio/virtio_ccw.c
> +++ b/drivers/s390/virtio/virtio_ccw.c
> @@ -530,6 +530,9 @@ static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
> err = -ENOMEM;
> goto out_err;
> }
> +
> + vq->num_max = info->num;
> +
> /* it may have been reduced */
> info->num = virtqueue_get_vring_size(vq);
>
> diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
> index 083ff1eb743d..a20d5a6b5819 100644
> --- a/drivers/virtio/virtio_mmio.c
> +++ b/drivers/virtio/virtio_mmio.c
> @@ -403,6 +403,8 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int in
> goto error_new_virtqueue;
> }
>
> + vq->num_max = num;
> +
> /* Activate the queue */
> writel(virtqueue_get_vring_size(vq), vm_dev->base + VIRTIO_MMIO_QUEUE_NUM);
> if (vm_dev->version == 1) {
> diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c
> index a5e5721145c7..2257f1b3d8ae 100644
> --- a/drivers/virtio/virtio_pci_legacy.c
> +++ b/drivers/virtio/virtio_pci_legacy.c
> @@ -135,6 +135,8 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
> if (!vq)
> return ERR_PTR(-ENOMEM);
>
> + vq->num_max = num;
> +
> q_pfn = virtqueue_get_desc_addr(vq) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT;
> if (q_pfn >> 32) {
> dev_err(&vp_dev->pci_dev->dev,
> diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
> index 623906b4996c..e7e0b8c850f6 100644
> --- a/drivers/virtio/virtio_pci_modern.c
> +++ b/drivers/virtio/virtio_pci_modern.c
> @@ -218,6 +218,8 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
> if (!vq)
> return ERR_PTR(-ENOMEM);
>
> + vq->num_max = num;
> +
> /* activate the queue */
> vp_modern_set_queue_size(mdev, index, virtqueue_get_vring_size(vq));
> vp_modern_queue_address(mdev, index, virtqueue_get_desc_addr(vq),
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index a5ec724c01d8..4cac600856ad 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -2385,6 +2385,20 @@ void vring_transport_features(struct virtio_device *vdev)
> }
> EXPORT_SYMBOL_GPL(vring_transport_features);
>
> +/**
> + * virtqueue_get_vring_max_size - return the max size of the virtqueue's vring
> + * @_vq: the struct virtqueue containing the vring of interest.
> + *
> + * Returns the max size of the vring.
> + *
> + * Unlike other operations, this need not be serialized.
> + */
> +unsigned int virtqueue_get_vring_max_size(struct virtqueue *_vq)
> +{
> + return _vq->num_max;
> +}
> +EXPORT_SYMBOL_GPL(virtqueue_get_vring_max_size);
> +
> /**
> * virtqueue_get_vring_size - return the size of the virtqueue's vring
> * @_vq: the struct virtqueue containing the vring of interest.
> diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
> index c40f7deb6b5a..9670cc79371d 100644
> --- a/drivers/virtio/virtio_vdpa.c
> +++ b/drivers/virtio/virtio_vdpa.c
> @@ -183,6 +183,8 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
> goto error_new_virtqueue;
> }
>
> + vq->num_max = max_num;
> +
> /* Setup virtqueue callback */
> cb.callback = callback ? virtio_vdpa_virtqueue_cb : NULL;
> cb.private = info;
> diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> index d8fdf170637c..a82620032e43 100644
> --- a/include/linux/virtio.h
> +++ b/include/linux/virtio.h
> @@ -31,6 +31,7 @@ struct virtqueue {
> struct virtio_device *vdev;
> unsigned int index;
> unsigned int num_free;
> + unsigned int num_max;
A question, since we export virtqueue to drivers, this means they can
access vq->num_max directly.
So we probably don't need a helper here.
Thanks
> void *priv;
> };
>
> @@ -80,6 +81,7 @@ bool virtqueue_enable_cb_delayed(struct virtqueue *vq);
>
> void *virtqueue_detach_unused_buf(struct virtqueue *vq);
>
> +unsigned int virtqueue_get_vring_max_size(struct virtqueue *vq);
> unsigned int virtqueue_get_vring_size(struct virtqueue *vq);
>
> bool virtqueue_is_broken(struct virtqueue *vq);
> --
> 2.31.0
>
