1 files changed, 111 insertions, 0 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
new file mode 100644
index 000000000000..35e188cf4ea4
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/tx.c
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/* Copyright (c) 2019 Mellanox Technologies. */
+
+#include "tx.h"
+#include "umem.h"
+#include "en/xdp.h"
+#include "en/params.h"
+#include <net/xdp_sock.h>
+
+int mlx5e_xsk_async_xmit(struct net_device *dev, u32 qid)
+{
+	struct mlx5e_priv *priv = netdev_priv(dev);
+	struct mlx5e_params *params = &priv->channels.params;
+	struct mlx5e_channel *c;
+	u16 ix;
+
+	if (unlikely(!mlx5e_xdp_is_open(priv)))
+		return -ENETDOWN;
+
+	if (unlikely(!mlx5e_qid_get_ch_if_in_group(params, qid, MLX5E_RQ_GROUP_XSK, &ix)))
+		return -EINVAL;
+
+	c = priv->channels.c[ix];
+
+	if (unlikely(!test_bit(MLX5E_CHANNEL_STATE_XSK, c->state)))
+		return -ENXIO;
+
+	if (!napi_if_scheduled_mark_missed(&c->napi)) {
+		spin_lock(&c->xskicosq_lock);
+		mlx5e_trigger_irq(&c->xskicosq);
+		spin_unlock(&c->xskicosq_lock);
+	}
+
+	return 0;
+}
+
+/* When TX fails (because of the size of the packet), we need to get completions
+ * in order, so post a NOP to get a CQE. Since AF_XDP doesn't distinguish
+ * between successful TX and errors, handling in mlx5e_poll_xdpsq_cq is the
+ * same.
+ */
+static void mlx5e_xsk_tx_post_err(struct mlx5e_xdpsq *sq,
+				  struct mlx5e_xdp_info *xdpi)
+{
+	u16 pi = mlx5_wq_cyc_ctr2ix(&sq->wq, sq->pc);
+	struct mlx5e_xdp_wqe_info *wi = &sq->db.wqe_info[pi];
+	struct mlx5e_tx_wqe *nopwqe;
+
+	wi->num_wqebbs = 1;
+	wi->num_pkts = 1;
+
+	nopwqe = mlx5e_post_nop(&sq->wq, sq->sqn, &sq->pc);
+	mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo, xdpi);
+	sq->doorbell_cseg = &nopwqe->ctrl;
+}
+
+bool mlx5e_xsk_tx(struct mlx5e_xdpsq *sq, unsigned int budget)
+{
+	struct xdp_umem *umem = sq->umem;
+	struct mlx5e_xdp_info xdpi;
+	struct mlx5e_xdp_xmit_data xdptxd;
+	bool work_done = true;
+	bool flush = false;
+
+	xdpi.mode = MLX5E_XDP_XMIT_MODE_XSK;
+
+	for (; budget; budget--) {
+		int check_result = sq->xmit_xdp_frame_check(sq);
+		struct xdp_desc desc;
+
+		if (unlikely(check_result < 0)) {
+			work_done = false;
+			break;
+		}
+
+		if (!xsk_umem_consume_tx(umem, &desc)) {
+			/* TX will get stuck until something wakes it up by
+			 * triggering NAPI. Currently it's expected that the
+			 * application calls sendto() if there are consumed, but
+			 * not completed frames.
+			 */
+			break;
+		}
+
+		xdptxd.dma_addr = xdp_umem_get_dma(umem, desc.addr);
+		xdptxd.data = xdp_umem_get_data(umem, desc.addr);
+		xdptxd.len = desc.len;
+
+		dma_sync_single_for_device(sq->pdev, xdptxd.dma_addr,
+					   xdptxd.len, DMA_BIDIRECTIONAL);
+
+		if (unlikely(!sq->xmit_xdp_frame(sq, &xdptxd, &xdpi, check_result))) {
+			if (sq->mpwqe.wqe)
+				mlx5e_xdp_mpwqe_complete(sq);
+
+			mlx5e_xsk_tx_post_err(sq, &xdpi);
+		}
+
+		flush = true;
+	}
+
+	if (flush) {
+		if (sq->mpwqe.wqe)
+			mlx5e_xdp_mpwqe_complete(sq);
+		mlx5e_xmit_xdp_doorbell(sq);
+
+		xsk_umem_consume_tx_done(umem);
+	}
+
+	return !(budget && work_done);
+}