Re: [RFC PATCH 08/24] vdpa: introduce virtqueue groups

From: Eugenio Perez Martin
Date: Mon Sep 28 2020 - 11:45:25 EST


On Thu, Sep 24, 2020 at 5:23 AM Jason Wang <jasowang@xxxxxxxxxx> wrote:
>
> This patch introduces virtqueue groups to vDPA device. The virtqueue
> group is the minimal set of virtqueues that must share an address
> space. And the adddress space identifier could only be attached to
> a specific virtqueue group.
>
> A new mandated bus operation is introduced to get the virtqueue group
> ID for a specific virtqueue.
>
> All the vDPA device drivers were converted to simply support a single
> virtqueue group.
>
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
> ---
> drivers/vdpa/ifcvf/ifcvf_main.c | 9 ++++++++-
> drivers/vdpa/mlx5/net/mlx5_vnet.c | 8 +++++++-
> drivers/vdpa/vdpa.c | 4 +++-
> drivers/vdpa/vdpa_sim/vdpa_sim.c | 11 ++++++++++-
> include/linux/vdpa.h | 12 +++++++++---
> 5 files changed, 37 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
> index 076d7ac5e723..e6a0be374e51 100644
> --- a/drivers/vdpa/ifcvf/ifcvf_main.c
> +++ b/drivers/vdpa/ifcvf/ifcvf_main.c
> @@ -327,6 +327,11 @@ static u32 ifcvf_vdpa_get_vq_align(struct vdpa_device *vdpa_dev)
> return IFCVF_QUEUE_ALIGNMENT;
> }
>
> +static u32 ifcvf_vdpa_get_vq_group(struct vdpa_device *vdpa, u16 idx)
> +{
> + return 0;
> +}
> +
> static void ifcvf_vdpa_get_config(struct vdpa_device *vdpa_dev,
> unsigned int offset,
> void *buf, unsigned int len)
> @@ -387,6 +392,7 @@ static const struct vdpa_config_ops ifc_vdpa_ops = {
> .get_device_id = ifcvf_vdpa_get_device_id,
> .get_vendor_id = ifcvf_vdpa_get_vendor_id,
> .get_vq_align = ifcvf_vdpa_get_vq_align,
> + .get_vq_group = ifcvf_vdpa_get_vq_group,
> .get_config = ifcvf_vdpa_get_config,
> .set_config = ifcvf_vdpa_set_config,
> .set_config_cb = ifcvf_vdpa_set_config_cb,
> @@ -434,7 +440,8 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>
> adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa,
> dev, &ifc_vdpa_ops,
> - IFCVF_MAX_QUEUE_PAIRS * 2);
> + IFCVF_MAX_QUEUE_PAIRS * 2, 1);
> +
> if (adapter == NULL) {
> IFCVF_ERR(pdev, "Failed to allocate vDPA structure");
> return -ENOMEM;
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index 9df69d5efe8c..4e480f4f754e 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -1428,6 +1428,11 @@ static u32 mlx5_vdpa_get_vq_align(struct vdpa_device *vdev)
> return PAGE_SIZE;
> }
>
> +static u32 mlx5_vdpa_get_vq_group(struct vdpa_device *vdpa, u16 idx)
> +{
> + return 0;
> +}
> +
> enum { MLX5_VIRTIO_NET_F_GUEST_CSUM = 1 << 9,
> MLX5_VIRTIO_NET_F_CSUM = 1 << 10,
> MLX5_VIRTIO_NET_F_HOST_TSO6 = 1 << 11,
> @@ -1838,6 +1843,7 @@ static const struct vdpa_config_ops mlx5_vdpa_ops = {
> .get_vq_notification = mlx5_get_vq_notification,
> .get_vq_irq = mlx5_get_vq_irq,
> .get_vq_align = mlx5_vdpa_get_vq_align,
> + .get_vq_group = mlx5_vdpa_get_vq_group,
> .get_features = mlx5_vdpa_get_features,
> .set_features = mlx5_vdpa_set_features,
> .set_config_cb = mlx5_vdpa_set_config_cb,
> @@ -1925,7 +1931,7 @@ void *mlx5_vdpa_add_dev(struct mlx5_core_dev *mdev)
> max_vqs = min_t(u32, max_vqs, MLX5_MAX_SUPPORTED_VQS);
>
> ndev = vdpa_alloc_device(struct mlx5_vdpa_net, mvdev.vdev, mdev->device, &mlx5_vdpa_ops,
> - 2 * mlx5_vdpa_max_qps(max_vqs));
> + 2 * mlx5_vdpa_max_qps(max_vqs), 1);
> if (IS_ERR(ndev))
> return ndev;
>
> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
> index a69ffc991e13..46399746ec7c 100644
> --- a/drivers/vdpa/vdpa.c
> +++ b/drivers/vdpa/vdpa.c
> @@ -62,6 +62,7 @@ static void vdpa_release_dev(struct device *d)
> * @parent: the parent device
> * @config: the bus operations that is supported by this device
> * @nvqs: number of virtqueues supported by this device
> + * @ngroups: number of groups supported by this device

Hi!

Maybe the description of "ngroups" could be "number of *virtqueue*
groups supported by this device"? I think that it could be needed in
some contexts reading the code.

Thanks!

> * @size: size of the parent structure that contains private data
> *
> * Driver should use vdpa_alloc_device() wrapper macro instead of
> @@ -72,7 +73,7 @@ static void vdpa_release_dev(struct device *d)
> */
> struct vdpa_device *__vdpa_alloc_device(struct device *parent,
> const struct vdpa_config_ops *config,
> - int nvqs,
> + int nvqs, unsigned int ngroups,
> size_t size)
> {
> struct vdpa_device *vdev;
> @@ -100,6 +101,7 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
> vdev->config = config;
> vdev->features_valid = false;
> vdev->nvqs = nvqs;
> + vdev->ngroups = ngroups;
>
> err = dev_set_name(&vdev->dev, "vdpa%u", vdev->index);
> if (err)
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> index 62d640327145..6669c561bc6e 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> @@ -75,6 +75,7 @@ struct vdpasim {
> u32 status;
> u32 generation;
> u64 features;
> + u32 groups;
> /* spinlock to synchronize iommu table */
> spinlock_t iommu_lock;
> };
> @@ -352,7 +353,8 @@ static struct vdpasim *vdpasim_create(void)
> else
> ops = &vdpasim_net_config_ops;
>
> - vdpasim = vdpa_alloc_device(struct vdpasim, vdpa, NULL, ops, VDPASIM_VQ_NUM);
> + vdpasim = vdpa_alloc_device(struct vdpasim, vdpa, NULL, ops,
> + VDPASIM_VQ_NUM, 1);
> if (!vdpasim)
> goto err_alloc;
>
> @@ -481,6 +483,11 @@ static u32 vdpasim_get_vq_align(struct vdpa_device *vdpa)
> return VDPASIM_QUEUE_ALIGN;
> }
>
> +static u32 vdpasim_get_vq_group(struct vdpa_device *vdpa, u16 idx)
> +{
> + return 0;
> +}
> +
> static u64 vdpasim_get_features(struct vdpa_device *vdpa)
> {
> return vdpasim_features;
> @@ -646,6 +653,7 @@ static const struct vdpa_config_ops vdpasim_net_config_ops = {
> .set_vq_state = vdpasim_set_vq_state,
> .get_vq_state = vdpasim_get_vq_state,
> .get_vq_align = vdpasim_get_vq_align,
> + .get_vq_group = vdpasim_get_vq_group,
> .get_features = vdpasim_get_features,
> .set_features = vdpasim_set_features,
> .set_config_cb = vdpasim_set_config_cb,
> @@ -672,6 +680,7 @@ static const struct vdpa_config_ops vdpasim_net_batch_config_ops = {
> .set_vq_state = vdpasim_set_vq_state,
> .get_vq_state = vdpasim_get_vq_state,
> .get_vq_align = vdpasim_get_vq_align,
> + .get_vq_group = vdpasim_get_vq_group,
> .get_features = vdpasim_get_features,
> .set_features = vdpasim_set_features,
> .set_config_cb = vdpasim_set_config_cb,
> diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
> index df169c2f5c0f..d829512efd27 100644
> --- a/include/linux/vdpa.h
> +++ b/include/linux/vdpa.h
> @@ -51,6 +51,7 @@ struct vdpa_device {
> unsigned int index;
> bool features_valid;
> int nvqs;
> + unsigned int ngroups;
> };
>
> /**
> @@ -109,6 +110,10 @@ struct vdpa_device {
> * for the device
> * @vdev: vdpa device
> * Returns virtqueue algin requirement
> + * @get_vq_group: Get the group id for a specific virtqueue
> + * @vdev: vdpa device
> + * @idx: virtqueue index
> + * Returns u32: group id for this virtqueue
> * @get_features: Get virtio features supported by the device
> * @vdev: vdpa device
> * Returns the virtio features support by the
> @@ -203,6 +208,7 @@ struct vdpa_config_ops {
>
> /* Device ops */
> u32 (*get_vq_align)(struct vdpa_device *vdev);
> + u32 (*get_vq_group)(struct vdpa_device *vdev, u16 idx);
> u64 (*get_features)(struct vdpa_device *vdev);
> int (*set_features)(struct vdpa_device *vdev, u64 features);
> void (*set_config_cb)(struct vdpa_device *vdev,
> @@ -230,12 +236,12 @@ struct vdpa_config_ops {
>
> struct vdpa_device *__vdpa_alloc_device(struct device *parent,
> const struct vdpa_config_ops *config,
> - int nvqs,
> + int nvqs, unsigned int ngroups,
> size_t size);
>
> -#define vdpa_alloc_device(dev_struct, member, parent, config, nvqs) \
> +#define vdpa_alloc_device(dev_struct, member, parent, config, nvqs, ngroups) \
> container_of(__vdpa_alloc_device( \
> - parent, config, nvqs, \
> + parent, config, nvqs, ngroups, \
> sizeof(dev_struct) + \
> BUILD_BUG_ON_ZERO(offsetof( \
> dev_struct, member))), \
> --
> 2.20.1
>