diff options
Diffstat (limited to 'drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c')
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c index 03b2a9f9c589..cad34d6f5f45 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c @@ -33,6 +33,26 @@ #include <linux/bpf_trace.h> #include "en/xdp.h" +int mlx5e_xdp_max_mtu(struct mlx5e_params *params) +{ + int hr = NET_IP_ALIGN + XDP_PACKET_HEADROOM; + + /* Let S := SKB_DATA_ALIGN(sizeof(struct skb_shared_info)). + * The condition checked in mlx5e_rx_is_linear_skb is: + * SKB_DATA_ALIGN(sw_mtu + hard_mtu + hr) + S <= PAGE_SIZE (1) + * (Note that hw_mtu == sw_mtu + hard_mtu.) + * What is returned from this function is: + * max_mtu = PAGE_SIZE - S - hr - hard_mtu (2) + * After assigning sw_mtu := max_mtu, the left side of (1) turns to + * SKB_DATA_ALIGN(PAGE_SIZE - S) + S, which is equal to PAGE_SIZE, + * because both PAGE_SIZE and S are already aligned. Any number greater + * than max_mtu would make the left side of (1) greater than PAGE_SIZE, + * so max_mtu is the maximum MTU allowed. + */ + + return MLX5E_HW2SW_MTU(params, SKB_MAX_HEAD(hr)); +} + static inline bool mlx5e_xmit_xdp_buff(struct mlx5e_xdpsq *sq, struct mlx5e_dma_info *di, struct xdp_buff *xdp) @@ -304,9 +324,9 @@ bool mlx5e_poll_xdpsq_cq(struct mlx5e_cq *cq, struct mlx5e_rq *rq) mlx5e_xdpi_fifo_pop(xdpi_fifo); if (is_redirect) { - xdp_return_frame(xdpi.xdpf); dma_unmap_single(sq->pdev, xdpi.dma_addr, xdpi.xdpf->len, DMA_TO_DEVICE); + xdp_return_frame(xdpi.xdpf); } else { /* Recycle RX page */ mlx5e_page_release(rq, &xdpi.di, true); @@ -345,9 +365,9 @@ void mlx5e_free_xdpsq_descs(struct mlx5e_xdpsq *sq, struct mlx5e_rq *rq) mlx5e_xdpi_fifo_pop(xdpi_fifo); if (is_redirect) { - xdp_return_frame(xdpi.xdpf); dma_unmap_single(sq->pdev, xdpi.dma_addr, xdpi.xdpf->len, DMA_TO_DEVICE); + xdp_return_frame(xdpi.xdpf); } else { /* Recycle RX page */ mlx5e_page_release(rq, &xdpi.di, false); |