Commit 124d0d8d authored by Tariq Toukan's avatar Tariq Toukan Committed by David S. Miller
Browse files

net/mlx5e: XDP, Remove un-established assumptions on XDP buffer 



Remove the assumption of non-zero linear length in the XDP xmit
function, used to serve both internal XDP_TX operations as well as
redirected-in requests.

Do not apply the MLX5E_XDP_MIN_INLINE check unless necessary.

Reviewed-by: default avatarSaeed Mahameed <saeedm@nvidia.com>
Signed-off-by: default avatarTariq Toukan <tariqt@nvidia.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 20409abe

drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c

+22 −14
Original line number Diff line number Diff line
@@ -477,18 +477,26 @@ mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd, 
	u16 ds_cnt, inline_hdr_sz;

	u8 num_wqebbs = 1;

	int num_frags = 0;

	bool inline_ok;

	bool linear;

	u16 pi;



	struct mlx5e_xdpsq_stats *stats = sq->stats;



	if (unlikely(dma_len < MLX5E_XDP_MIN_INLINE || sq->hw_mtu < dma_len)) {

	inline_ok = sq->min_inline_mode == MLX5_INLINE_MODE_NONE ||

		dma_len >= MLX5E_XDP_MIN_INLINE;



	if (unlikely(!inline_ok || sq->hw_mtu < dma_len)) {

		stats->err++;

		return false;

	}



	ds_cnt = MLX5E_TX_WQE_EMPTY_DS_COUNT + 1;

	inline_hdr_sz = 0;

	if (sq->min_inline_mode != MLX5_INLINE_MODE_NONE)

		ds_cnt++;

		inline_hdr_sz = MLX5E_XDP_MIN_INLINE;



	linear = !!(dma_len - inline_hdr_sz);

	ds_cnt = MLX5E_TX_WQE_EMPTY_DS_COUNT + linear + !!inline_hdr_sz;



	/* check_result must be 0 if sinfo is passed. */

	if (!check_result) {
@@ -517,22 +525,23 @@ mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd, 
	eseg = &wqe->eth;

	dseg = wqe->data;



	inline_hdr_sz = 0;



	/* copy the inline part if required */

	if (sq->min_inline_mode != MLX5_INLINE_MODE_NONE) {

	if (inline_hdr_sz) {

		memcpy(eseg->inline_hdr.start, xdptxd->data, sizeof(eseg->inline_hdr.start));

		memcpy(dseg, xdptxd->data + sizeof(eseg->inline_hdr.start),

		       MLX5E_XDP_MIN_INLINE - sizeof(eseg->inline_hdr.start));

		dma_len  -= MLX5E_XDP_MIN_INLINE;

		dma_addr += MLX5E_XDP_MIN_INLINE;

		inline_hdr_sz = MLX5E_XDP_MIN_INLINE;

		       inline_hdr_sz - sizeof(eseg->inline_hdr.start));

		dma_len  -= inline_hdr_sz;

		dma_addr += inline_hdr_sz;

		dseg++;

	}



	/* write the dma part */

	if (linear) {

		dseg->addr       = cpu_to_be64(dma_addr);

		dseg->byte_count = cpu_to_be32(dma_len);

		dseg->lkey       = sq->mkey_be;

		dseg++;

	}



	cseg->opmod_idx_opcode = cpu_to_be32((sq->pc << 8) | MLX5_OPCODE_SEND);
@@ -543,7 +552,6 @@ mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd, 
		memset(eseg, 0, sizeof(*eseg) - sizeof(eseg->trailer));



		eseg->inline_hdr.sz = cpu_to_be16(inline_hdr_sz);

		dseg->lkey = sq->mkey_be;



		for (i = 0; i < num_frags; i++) {

			skb_frag_t *frag = &xdptxdf->sinfo->frags[i];
@@ -553,10 +561,10 @@ mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd, 
				page_pool_get_dma_addr(skb_frag_page(frag)) +

				skb_frag_off(frag);



			dseg++;

			dseg->addr = cpu_to_be64(addr);

			dseg->byte_count = cpu_to_be32(skb_frag_size(frag));

			dseg->lkey = sq->mkey_be;

			dseg++;

		}



		cseg->qpn_ds = cpu_to_be32((sq->sqn << 8) | ds_cnt);

drivers/net/ethernet/mellanox/mlx5/core/en_main.c

+0 −4
Original line number Diff line number Diff line
@@ -1886,7 +1886,6 @@ int mlx5e_open_xdpsq(struct mlx5e_channel *c, struct mlx5e_params *params, 
			struct mlx5e_tx_wqe      *wqe  = mlx5_wq_cyc_get_wqe(&sq->wq, i);

			struct mlx5_wqe_ctrl_seg *cseg = &wqe->ctrl;

			struct mlx5_wqe_eth_seg  *eseg = &wqe->eth;

			struct mlx5_wqe_data_seg *dseg;



			sq->db.wqe_info[i] = (struct mlx5e_xdp_wqe_info) {

				.num_wqebbs = 1,
@@ -1895,9 +1894,6 @@ int mlx5e_open_xdpsq(struct mlx5e_channel *c, struct mlx5e_params *params, 


			cseg->qpn_ds = cpu_to_be32((sq->sqn << 8) | ds_cnt);

			eseg->inline_hdr.sz = cpu_to_be16(inline_hdr_sz);



			dseg = (struct mlx5_wqe_data_seg *)cseg + (ds_cnt - 1);

			dseg->lkey = sq->mkey_be;

		}

	}