Re: [PATCH v9 01/32] virtio: add helper virtqueue_get_vring_max_size()

Jason Wang
2022-04-12T02:41:26Z

在 2022/4/6 上午11:43, Xuan Zhuo 写道:
> 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@linux.alibaba.com>
> ---
> 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 ba562d68dc04..904993d15a85 100644
> --- a/arch/um/drivers/virtio_uml.c
> +++ b/arch/um/drivers/virtio_uml.c
> @@ -945,6 +945,7 @@ 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 70ab496d0431..7611755d0ae2 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 = len;

I wonder if this is correct.

It looks to me len is counted in bytes:

/**
* struct rproc_vring - remoteproc vring state
* @va: virtual address
* @len: length, in bytes
* @da: device address
* @align: vring alignment
* @notifyid: rproc-specific unique vring index
* @rvdev: remote vdev
* @vq: the virtqueue of this vring
*/
struct rproc_vring {
void *va;
int len;
u32 da;
u32 align;
int notifyid;
struct rproc_vdev *rvdev;
struct virtqueue *vq;
};

Other looks good.

Thanks

> +
> rvring->vq = vq;
> vq->priv = rvring;
>
> diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
> index d35e7a3f7067..468da60b56c5 100644
> --- a/drivers/s390/virtio/virtio_ccw.c
> +++ b/drivers/s390/virtio/virtio_ccw.c
> @@ -529,6 +529,9 @@ 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 56128b9c46eb..a41abc8051b9 100644
> --- a/drivers/virtio/virtio_mmio.c
> +++ b/drivers/virtio/virtio_mmio.c
> @@ -390,6 +390,8 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index,
> 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 34141b9abe27..b68934fe6b5d 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 5455bc041fb6..86d301f272b8 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 962f1477b1fa..b87130c8f312 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -2371,6 +2371,20 @@ 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 7767a7f0119b..39e4c08eb0f2 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 = virtio_vdpa_virtqueue_cb;
> cb.private = info;
> diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> index 72292a62cd90..d59adc4be068 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;
> 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);