[PATCH net-next 2/5] net/mlx5e: XDP, Improve dma address calculation of linear part for XDP_TX
From: Tariq Toukan <tariqt@nvidia.com>
Date: 2026-03-19 07:52:15
Also in:
bpf, linux-rdma, lkml
Subsystem:
mellanox mlx5 core vpi driver, networking drivers, the rest, xdp (express data path) · Maintainers:
Saeed Mahameed, Leon Romanovsky, Tariq Toukan, Mark Bloch, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Alexei Starovoitov, Daniel Borkmann, David S. Miller, Jesper Dangaard Brouer, John Fastabend
From: Dragos Tatulea <dtatulea@nvidia.com> When calculating the dma address of the linear part of an XDP frame, the formula assumes that there is a single XDP buffer per page. Extend the formula to allow multiple XDP buffers per page by calculating the data offset in the page. This is a preparation for the upcoming removal of a single XDP buffer per page limitation when the formula will no longer be correct. Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com> Reviewed-by: Carolina Jubran <redacted> Signed-off-by: Tariq Toukan <tariqt@nvidia.com> --- drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
index 04e1b5fa4825..d3bab198c99c 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c@@ -123,7 +123,7 @@ mlx5e_xmit_xdp_buff(struct mlx5e_xdpsq *sq, struct mlx5e_rq *rq, * mode. */ - dma_addr = page_pool_get_dma_addr(page) + (xdpf->data - (void *)xdpf); + dma_addr = page_pool_get_dma_addr(page) + offset_in_page(xdpf->data); dma_sync_single_for_device(sq->pdev, dma_addr, xdptxd->len, DMA_BIDIRECTIONAL); if (xdptxd->has_frags) {
--
2.44.0