From: Eli Cohen <elic@nvidia.com>
Date: Mon, 21 Feb 2022 14:19:27 +0200
Subject: net/mlx5: Add support for configuring max device MTU
Patch-mainline: v5.18-rc1
Git-commit: 1e00e821e4ca6355c7fff9f69a4c5ecd78e348a0
References: jsc#PED-1549
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: Si-Wei Liu<si-wei.liu@oracle.com>
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220221121927.194728-1-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/vdpa/mlx5/net/mlx5_vnet.c | 32 +++++++++++++++++++++++++++++++-
1 file changed, 31 insertions(+), 1 deletion(-)
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -2565,6 +2565,28 @@ static int event_handler(struct notifier
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
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_
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);