For zero-copy (devmem, io_uring), the netdev DMA device used
is the parent device of the net device. However that is not
always accurate for mlx5 devices:
- SFs: The parent device is an auxdev.
- Multi-PF netdevs: The DMA device should be determined by
the queue.
This change implements the DMA device queue API that returns the DMA
device appropriately for all cases.
Signed-off-by: Dragos Tatulea <dtatulea@xxxxxxxxxx>
Reviewed-by: Mina Almasry <almasrymina@xxxxxxxxxx>
---
.../net/ethernet/mellanox/mlx5/core/en_main.c | 24 +++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 21bb88c5d3dc..0e48065a46eb 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -5625,12 +5625,36 @@ static int mlx5e_queue_start(struct net_device *dev, void *newq,
return 0;
}
+static struct device *mlx5e_queue_get_dma_dev(struct net_device *dev,
+ int queue_index)
+{
+ struct mlx5e_priv *priv = netdev_priv(dev);
+ struct mlx5e_channels *channels;
+ struct device *pdev = NULL;
+ struct mlx5e_channel *ch;
+
+ channels = &priv->channels;
+
+ mutex_lock(&priv->state_lock);
+
+ if (queue_index >= channels->num)
+ goto out;
+
+ ch = channels->c[queue_index];
+ pdev = ch->pdev;
+out:
+ mutex_unlock(&priv->state_lock);
+
+ return pdev;
+}
+
static const struct netdev_queue_mgmt_ops mlx5e_queue_mgmt_ops = {
.ndo_queue_mem_size = sizeof(struct mlx5_qmgmt_data),
.ndo_queue_mem_alloc = mlx5e_queue_mem_alloc,
.ndo_queue_mem_free = mlx5e_queue_mem_free,
.ndo_queue_start = mlx5e_queue_start,
.ndo_queue_stop = mlx5e_queue_stop,
+ .ndo_queue_get_dma_dev = mlx5e_queue_get_dma_dev,
};
static void mlx5e_build_nic_netdev(struct net_device *netdev)
--
2.50.1
