Commit 1e00e821 authored by Eli Cohen's avatar Eli Cohen Committed by Michael S. Tsirkin
Browse files

net/mlx5: Add support for configuring max device MTU 



Allow an admin creating a vdpa device to specify the max MTU for the
net device.

For example, to create a device with max MTU of 1000, the following
command can be used:

$ vdpa dev add name vdpa-a mgmtdev auxiliary/mlx5_core.sf.1 mtu 1000

This configuration mechanism assumes that vdpa is the sole real user of
the function. mlx5_core could theoretically change the mtu of the
function using the ip command on the mlx5_core net device but this
should not be done.

Reviewed-by: default avatarSi-Wei <Liu&lt;si-wei.liu@oracle.com>
Signed-off-by: default avatarEli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220221121927.194728-1-elic@nvidia.com


Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Acked-by: default avatarJason Wang <jasowang@redhat.com>
parent ea993de1

drivers/vdpa/mlx5/net/mlx5_vnet.c

+31 −1
Original line number Diff line number Diff line
@@ -2565,6 +2565,28 @@ static int event_handler(struct notifier_block *nb, unsigned long event, void *p 
	return ret;

}



static int config_func_mtu(struct mlx5_core_dev *mdev, u16 mtu)

{

	int inlen = MLX5_ST_SZ_BYTES(modify_nic_vport_context_in);

	void *in;

	int err;



	in = kvzalloc(inlen, GFP_KERNEL);

	if (!in)

		return -ENOMEM;



	MLX5_SET(modify_nic_vport_context_in, in, field_select.mtu, 1);

	MLX5_SET(modify_nic_vport_context_in, in, nic_vport_context.mtu,

		 mtu + MLX5V_ETH_HARD_MTU);

	MLX5_SET(modify_nic_vport_context_in, in, opcode,

		 MLX5_CMD_OP_MODIFY_NIC_VPORT_CONTEXT);



	err = mlx5_cmd_exec_in(mdev, modify_nic_vport_context, in);



	kvfree(in);

	return err;

}



static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,

			     const struct vdpa_dev_set_config *add_config)

{
@@ -2624,6 +2646,13 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name, 
	init_mvqs(ndev);

	mutex_init(&ndev->reslock);

	config = &ndev->config;



	if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MTU)) {

		err = config_func_mtu(mdev, add_config->net.mtu);

		if (err)

			goto err_mtu;

	}



	err = query_mtu(mdev, &mtu);

	if (err)

		goto err_mtu;
@@ -2741,7 +2770,8 @@ static int mlx5v_probe(struct auxiliary_device *adev, 
	mgtdev->mgtdev.device = mdev->device;

	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_MAX_VQP) |

					  BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MTU);

	mgtdev->mgtdev.max_supported_vqs =

		MLX5_CAP_DEV_VDPA_EMULATION(mdev, max_num_virtio_queues) + 1;

	mgtdev->mgtdev.supported_features = get_supported_features(mdev);