[PATCH v2 7/7] vdpa/mlx5: support device features provisioning

From: Si-Wei Liu
Date: Tue Jan 31 2023 - 18:24:41 EST


This patch implements features provisioning for mlx5_vdpa.

1) Validate the provisioned features are a subset of the parent
features.
2) Clearing features that are not wanted by userspace.

For example:

# vdpa mgmtdev show
pci/0000:41:04.2:
supported_classes net
max_supported_vqs 65
dev_features CSUM GUEST_CSUM MTU MAC HOST_TSO4 HOST_TSO6 STATUS CTRL_VQ CTRL_VLAN MQ CTRL_MAC_ADDR VERSION_1 ACCESS_PLATFORM

1) Provision vDPA device with all features derived from the parent

# vdpa dev add name vdpa1 mgmtdev pci/0000:41:04.2
# vdpa dev config show
vdpa1: mac e4:11:c6:d3:45:f0 link up link_announce false max_vq_pairs 1 mtu 1500
negotiated_features CSUM GUEST_CSUM MTU HOST_TSO4 HOST_TSO6 STATUS CTRL_VQ CTRL_VLAN MQ CTRL_MAC_ADDR VERSION_1 ACCESS_PLATFORM

2) Provision vDPA device with a subset of parent features

# vdpa dev add name vdpa1 mgmtdev pci/0000:41:04.2 device_features 0x300020000
# vdpa dev config show
vdpa1:
negotiated_features CTRL_VQ VERSION_1 ACCESS_PLATFORM

Signed-off-by: Si-Wei Liu <si-wei.liu@xxxxxxxxxx>
---
drivers/vdpa/mlx5/net/mlx5_vnet.c | 49 ++++++++++++++++++++++++++++++++++-----
1 file changed, 43 insertions(+), 6 deletions(-)

diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 3d49eae..b40dd1a 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -2183,6 +2183,7 @@ static u64 get_supported_features(struct mlx5_core_dev *mdev)
mlx_vdpa_features |= BIT_ULL(VIRTIO_NET_F_STATUS);
mlx_vdpa_features |= BIT_ULL(VIRTIO_NET_F_MTU);
mlx_vdpa_features |= BIT_ULL(VIRTIO_NET_F_CTRL_VLAN);
+ mlx_vdpa_features |= BIT_ULL(VIRTIO_NET_F_MAC);

return mlx_vdpa_features;
}
@@ -3062,6 +3063,7 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
struct mlx5_vdpa_dev *mvdev;
struct mlx5_vdpa_net *ndev;
struct mlx5_core_dev *mdev;
+ u64 device_features;
u32 max_vqs;
u16 mtu;
int err;
@@ -3070,6 +3072,24 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
return -ENOSPC;

mdev = mgtdev->madev->mdev;
+ device_features = mgtdev->mgtdev.supported_features;
+ if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_FEATURES)) {
+ if (add_config->device_features & ~device_features) {
+ dev_warn(mdev->device,
+ "The provisioned features 0x%llx are not supported by this device with features 0x%llx\n",
+ add_config->device_features, device_features);
+ return -EINVAL;
+ }
+ device_features &= add_config->device_features;
+ }
+ if (!(device_features & BIT_ULL(VIRTIO_F_VERSION_1) &&
+ device_features & BIT_ULL(VIRTIO_F_ACCESS_PLATFORM))) {
+ dev_warn(mdev->device,
+ "Must provision minimum features 0x%llx for this device",
+ BIT_ULL(VIRTIO_F_VERSION_1) | BIT_ULL(VIRTIO_F_ACCESS_PLATFORM));
+ return -EOPNOTSUPP;
+ }
+
if (!(MLX5_CAP_DEV_VDPA_EMULATION(mdev, virtio_queue_type) &
MLX5_VIRTIO_EMULATION_CAP_VIRTIO_QUEUE_TYPE_SPLIT)) {
dev_warn(mdev->device, "missing support for split virtqueues\n");
@@ -3098,7 +3118,6 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
if (IS_ERR(ndev))
return PTR_ERR(ndev);

- ndev->mvdev.mlx_features = mgtdev->mgtdev.supported_features;
ndev->mvdev.max_vqs = max_vqs;
mvdev = &ndev->mvdev;
mvdev->mdev = mdev;
@@ -3137,7 +3156,9 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,

if (add_config->mask & (1 << VDPA_ATTR_DEV_NET_CFG_MACADDR)) {
memcpy(ndev->config.mac, add_config->net.mac, ETH_ALEN);
- } else {
+ /* No bother setting mac address in config if not going to provision _F_MAC */
+ } else if ((add_config->mask & BIT_ULL(VDPA_ATTR_DEV_FEATURES)) == 0 ||
+ device_features & BIT_ULL(VIRTIO_NET_F_MAC)) {
err = mlx5_query_nic_vport_mac_address(mdev, 0, 0, config->mac);
if (err)
goto err_alloc;
@@ -3148,11 +3169,26 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
err = mlx5_mpfs_add_mac(pfmdev, config->mac);
if (err)
goto err_alloc;
-
- ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_NET_F_MAC);
+ } else if ((add_config->mask & BIT_ULL(VDPA_ATTR_DEV_FEATURES)) == 0) {
+ /*
+ * We used to clear _F_MAC feature bit if seeing
+ * zero mac address when device features are not
+ * specifically provisioned. Keep the behaviour
+ * so old scripts do not break.
+ */
+ device_features &= ~BIT_ULL(VIRTIO_NET_F_MAC);
+ } else if (device_features & BIT_ULL(VIRTIO_NET_F_MAC)) {
+ /* Don't provision zero mac address for _F_MAC */
+ mlx5_vdpa_warn(&ndev->mvdev,
+ "No mac address provisioned?\n");
+ err = -EINVAL;
+ goto err_alloc;
}

- config->max_virtqueue_pairs = cpu_to_mlx5vdpa16(mvdev, max_vqs / 2);
+ if (device_features & BIT_ULL(VIRTIO_NET_F_MQ))
+ config->max_virtqueue_pairs = cpu_to_mlx5vdpa16(mvdev, max_vqs / 2);
+
+ ndev->mvdev.mlx_features = device_features;
mvdev->vdev.dma_dev = &mdev->pdev->dev;
err = mlx5_vdpa_alloc_resources(&ndev->mvdev);
if (err)
@@ -3249,7 +3285,8 @@ static int mlx5v_probe(struct auxiliary_device *adev,
mgtdev->mgtdev.id_table = id_table;
mgtdev->mgtdev.config_attr_mask = BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MACADDR) |
BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP) |
- BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MTU);
+ BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MTU) |
+ BIT_ULL(VDPA_ATTR_DEV_FEATURES);
mgtdev->mgtdev.max_supported_vqs =
MLX5_CAP_DEV_VDPA_EMULATION(mdev, max_num_virtio_queues) + 1;
mgtdev->mgtdev.supported_features = get_supported_features(mdev);
--
1.8.3.1