drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c - pub/scm/linux/kernel/git/linusw/linux-gpio - Git at Google

 /*
  * Copyright (c) 2018, Mellanox Technologies. All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
  * General Public License (GPL) Version 2, available from the file
  * COPYING in the main directory of this source tree, or the
  * OpenIB.org BSD license below:
  *
  *     Redistribution and use in source and binary forms, with or
  *     without modification, are permitted provided that the following
  *     conditions are met:
  *
  *      - Redistributions of source code must retain the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer.
  *
  *      - Redistributions in binary form must reproduce the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer in the documentation and/or other materials
  *        provided with the distribution.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */

 #include <linux/bpf_trace.h>
 #include "en/xdp.h"

 static inline bool
 mlx5e_xmit_xdp_buff(struct mlx5e_xdpsq *sq, struct mlx5e_dma_info *di,
 		    struct xdp_buff *xdp)
 {
 	struct mlx5e_xdp_info xdpi;

 	xdpi.xdpf = convert_to_xdp_frame(xdp);
 	if (unlikely(!xdpi.xdpf))
 		return false;
 	xdpi.dma_addr = di->addr + (xdpi.xdpf->data - (void *)xdpi.xdpf);
 	dma_sync_single_for_device(sq->pdev, xdpi.dma_addr,
 				   xdpi.xdpf->len, PCI_DMA_TODEVICE);
 	xdpi.di = *di;

 	return sq->xmit_xdp_frame(sq, &xdpi);
 }

 /* returns true if packet was consumed by xdp */
 bool mlx5e_xdp_handle(struct mlx5e_rq *rq, struct mlx5e_dma_info *di,
 		      void *va, u16 *rx_headroom, u32 *len)
 {
 	struct bpf_prog *prog = READ_ONCE(rq->xdp_prog);
 	struct xdp_buff xdp;
 	u32 act;
 	int err;

 	if (!prog)
 		return false;

 	xdp.data = va + *rx_headroom;
 	xdp_set_data_meta_invalid(&xdp);
 	xdp.data_end = xdp.data + *len;
 	xdp.data_hard_start = va;
 	xdp.rxq = &rq->xdp_rxq;

 	act = bpf_prog_run_xdp(prog, &xdp);
 	switch (act) {
 	case XDP_PASS:
 		*rx_headroom = xdp.data - xdp.data_hard_start;
 		*len = xdp.data_end - xdp.data;
 		return false;
 	case XDP_TX:
 		if (unlikely(!mlx5e_xmit_xdp_buff(&rq->xdpsq, di, &xdp)))
 			goto xdp_abort;
 		__set_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags); /* non-atomic */
 		return true;
 	case XDP_REDIRECT:
 		/* When XDP enabled then page-refcnt==1 here */
 		err = xdp_do_redirect(rq->netdev, &xdp, prog);
 		if (unlikely(err))
 			goto xdp_abort;
 		__set_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags);
 		rq->xdpsq.redirect_flush = true;
 		mlx5e_page_dma_unmap(rq, di);
 		rq->stats->xdp_redirect++;
 		return true;
 	default:
 		bpf_warn_invalid_xdp_action(act);
 		/* fall through */
 	case XDP_ABORTED:
 xdp_abort:
 		trace_xdp_exception(rq->netdev, prog, act);
 		/* fall through */
 	case XDP_DROP:
 		rq->stats->xdp_drop++;
 		return true;
 	}
 }

 static void mlx5e_xdp_mpwqe_session_start(struct mlx5e_xdpsq *sq)
 {
 	struct mlx5e_xdp_mpwqe *session = &sq->mpwqe;
 	struct mlx5_wq_cyc *wq = &sq->wq;
 	u8  wqebbs;
 	u16 pi;

 	mlx5e_xdpsq_fetch_wqe(sq, &session->wqe);

 	prefetchw(session->wqe->data);
 	session->ds_count = MLX5E_XDP_TX_EMPTY_DS_COUNT;

 	pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);

 /* The mult of MLX5_SEND_WQE_MAX_WQEBBS * MLX5_SEND_WQEBB_NUM_DS
  * (16 * 4 == 64) does not fit in the 6-bit DS field of Ctrl Segment.
  * We use a bound lower that MLX5_SEND_WQE_MAX_WQEBBS to let a
  * full-session WQE be cache-aligned.
  */
 #if L1_CACHE_BYTES < 128
 #define MLX5E_XDP_MPW_MAX_WQEBBS (MLX5_SEND_WQE_MAX_WQEBBS - 1)
 #else
 #define MLX5E_XDP_MPW_MAX_WQEBBS (MLX5_SEND_WQE_MAX_WQEBBS - 2)
 #endif

 	wqebbs = min_t(u16, mlx5_wq_cyc_get_contig_wqebbs(wq, pi),
 		       MLX5E_XDP_MPW_MAX_WQEBBS);

 	session->max_ds_count = MLX5_SEND_WQEBB_NUM_DS * wqebbs;
 }

 static void mlx5e_xdp_mpwqe_complete(struct mlx5e_xdpsq *sq)
 {
 	struct mlx5_wq_cyc       *wq    = &sq->wq;
 	struct mlx5e_xdp_mpwqe *session = &sq->mpwqe;
 	struct mlx5_wqe_ctrl_seg *cseg = &session->wqe->ctrl;
 	u16 ds_count = session->ds_count;
 	u16 pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);
 	struct mlx5e_xdp_wqe_info *wi = &sq->db.wqe_info[pi];

 	cseg->opmod_idx_opcode =
 		cpu_to_be32((sq->pc << 8) | MLX5_OPCODE_ENHANCED_MPSW);
 	cseg->qpn_ds = cpu_to_be32((sq->sqn << 8) | ds_count);

 	wi->num_wqebbs = DIV_ROUND_UP(ds_count, MLX5_SEND_WQEBB_NUM_DS);
 	wi->num_ds     = ds_count - MLX5E_XDP_TX_EMPTY_DS_COUNT;

 	sq->pc += wi->num_wqebbs;

 	sq->doorbell_cseg = cseg;

 	session->wqe = NULL; /* Close session */
 }

 static bool mlx5e_xmit_xdp_frame_mpwqe(struct mlx5e_xdpsq *sq,
 				       struct mlx5e_xdp_info *xdpi)
 {
 	struct mlx5e_xdp_mpwqe *session = &sq->mpwqe;
 	struct mlx5e_xdpsq_stats *stats = sq->stats;

 	dma_addr_t dma_addr    = xdpi->dma_addr;
 	struct xdp_frame *xdpf = xdpi->xdpf;
 	unsigned int dma_len   = xdpf->len;

 	if (unlikely(sq->hw_mtu < dma_len)) {
 		stats->err++;
 		return false;
 	}

 	if (unlikely(!session->wqe)) {
 		if (unlikely(!mlx5e_wqc_has_room_for(&sq->wq, sq->cc, sq->pc,
 						     MLX5_SEND_WQE_MAX_WQEBBS))) {
 			/* SQ is full, ring doorbell */
 			mlx5e_xmit_xdp_doorbell(sq);
 			stats->full++;
 			return false;
 		}

 		mlx5e_xdp_mpwqe_session_start(sq);
 	}

 	mlx5e_xdp_mpwqe_add_dseg(sq, dma_addr, dma_len);

 	if (unlikely(session->ds_count == session->max_ds_count))
 		mlx5e_xdp_mpwqe_complete(sq);

 	mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo, xdpi);
 	stats->xmit++;
 	return true;
 }

 static bool mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xdp_info *xdpi)
 {
 	struct mlx5_wq_cyc       *wq   = &sq->wq;
 	u16                       pi   = mlx5_wq_cyc_ctr2ix(wq, sq->pc);
 	struct mlx5e_tx_wqe      *wqe  = mlx5_wq_cyc_get_wqe(wq, pi);

 	struct mlx5_wqe_ctrl_seg *cseg = &wqe->ctrl;
 	struct mlx5_wqe_eth_seg  *eseg = &wqe->eth;
 	struct mlx5_wqe_data_seg *dseg = wqe->data;

 	struct xdp_frame *xdpf = xdpi->xdpf;
 	dma_addr_t dma_addr  = xdpi->dma_addr;
 	unsigned int dma_len = xdpf->len;

 	struct mlx5e_xdpsq_stats *stats = sq->stats;

 	prefetchw(wqe);

 	if (unlikely(dma_len < MLX5E_XDP_MIN_INLINE || sq->hw_mtu < dma_len)) {
 		stats->err++;
 		return false;
 	}

 	if (unlikely(!mlx5e_wqc_has_room_for(wq, sq->cc, sq->pc, 1))) {
 		/* SQ is full, ring doorbell */
 		mlx5e_xmit_xdp_doorbell(sq);
 		stats->full++;
 		return false;
 	}

 	cseg->fm_ce_se = 0;

 	/* copy the inline part if required */
 	if (sq->min_inline_mode != MLX5_INLINE_MODE_NONE) {
 		memcpy(eseg->inline_hdr.start, xdpf->data, MLX5E_XDP_MIN_INLINE);
 		eseg->inline_hdr.sz = cpu_to_be16(MLX5E_XDP_MIN_INLINE);
 		dma_len  -= MLX5E_XDP_MIN_INLINE;
 		dma_addr += MLX5E_XDP_MIN_INLINE;
 		dseg++;
 	}

 	/* write the dma part */
 	dseg->addr       = cpu_to_be64(dma_addr);
 	dseg->byte_count = cpu_to_be32(dma_len);

 	cseg->opmod_idx_opcode = cpu_to_be32((sq->pc << 8) | MLX5_OPCODE_SEND);

 	sq->pc++;

 	sq->doorbell_cseg = cseg;

 	mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo, xdpi);
 	stats->xmit++;
 	return true;
 }

 bool mlx5e_poll_xdpsq_cq(struct mlx5e_cq *cq, struct mlx5e_rq *rq)
 {
 	struct mlx5e_xdp_info_fifo *xdpi_fifo;
 	struct mlx5e_xdpsq *sq;
 	struct mlx5_cqe64 *cqe;
 	bool is_redirect;
 	u16 sqcc;
 	int i;

 	sq = container_of(cq, struct mlx5e_xdpsq, cq);

 	if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &sq->state)))
 		return false;

 	cqe = mlx5_cqwq_get_cqe(&cq->wq);
 	if (!cqe)
 		return false;

 	is_redirect = !rq;
 	xdpi_fifo = &sq->db.xdpi_fifo;

 	/* sq->cc must be updated only after mlx5_cqwq_update_db_record(),
 	 * otherwise a cq overrun may occur
 	 */
 	sqcc = sq->cc;

 	i = 0;
 	do {
 		u16 wqe_counter;
 		bool last_wqe;

 		mlx5_cqwq_pop(&cq->wq);

 		wqe_counter = be16_to_cpu(cqe->wqe_counter);

 		if (unlikely(get_cqe_opcode(cqe) != MLX5_CQE_REQ))
 			netdev_WARN_ONCE(sq->channel->netdev,
 					 "Bad OP in XDPSQ CQE: 0x%x\n",
 					 get_cqe_opcode(cqe));

 		do {
 			struct mlx5e_xdp_wqe_info *wi;
 			u16 ci, j;

 			last_wqe = (sqcc == wqe_counter);
 			ci = mlx5_wq_cyc_ctr2ix(&sq->wq, sqcc);
 			wi = &sq->db.wqe_info[ci];

 			sqcc += wi->num_wqebbs;

 			for (j = 0; j < wi->num_ds; j++) {
 				struct mlx5e_xdp_info xdpi =
 					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);
 				} else {
 					/* Recycle RX page */
 					mlx5e_page_release(rq, &xdpi.di, true);
 				}
 			}
 		} while (!last_wqe);
 	} while ((++i < MLX5E_TX_CQ_POLL_BUDGET) && (cqe = mlx5_cqwq_get_cqe(&cq->wq)));

 	sq->stats->cqes += i;

 	mlx5_cqwq_update_db_record(&cq->wq);

 	/* ensure cq space is freed before enabling more cqes */
 	wmb();

 	sq->cc = sqcc;
 	return (i == MLX5E_TX_CQ_POLL_BUDGET);
 }

 void mlx5e_free_xdpsq_descs(struct mlx5e_xdpsq *sq, struct mlx5e_rq *rq)
 {
 	struct mlx5e_xdp_info_fifo *xdpi_fifo = &sq->db.xdpi_fifo;
 	bool is_redirect = !rq;

 	while (sq->cc != sq->pc) {
 		struct mlx5e_xdp_wqe_info *wi;
 		u16 ci, i;

 		ci = mlx5_wq_cyc_ctr2ix(&sq->wq, sq->cc);
 		wi = &sq->db.wqe_info[ci];

 		sq->cc += wi->num_wqebbs;

 		for (i = 0; i < wi->num_ds; i++) {
 			struct mlx5e_xdp_info xdpi =
 				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);
 			} else {
 				/* Recycle RX page */
 				mlx5e_page_release(rq, &xdpi.di, false);
 			}
 		}
 	}
 }

 int mlx5e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
 		   u32 flags)
 {
 	struct mlx5e_priv *priv = netdev_priv(dev);
 	struct mlx5e_xdpsq *sq;
 	int drops = 0;
 	int sq_num;
 	int i;

 	/* this flag is sufficient, no need to test internal sq state */
 	if (unlikely(!mlx5e_xdp_tx_is_enabled(priv)))
 		return -ENETDOWN;

 	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
 		return -EINVAL;

 	sq_num = smp_processor_id();

 	if (unlikely(sq_num >= priv->channels.num))
 		return -ENXIO;

 	sq = &priv->channels.c[sq_num]->xdpsq;

 	for (i = 0; i < n; i++) {
 		struct xdp_frame *xdpf = frames[i];
 		struct mlx5e_xdp_info xdpi;

 		xdpi.dma_addr = dma_map_single(sq->pdev, xdpf->data, xdpf->len,
 					       DMA_TO_DEVICE);
 		if (unlikely(dma_mapping_error(sq->pdev, xdpi.dma_addr))) {
 			xdp_return_frame_rx_napi(xdpf);
 			drops++;
 			continue;
 		}

 		xdpi.xdpf = xdpf;

 		if (unlikely(!sq->xmit_xdp_frame(sq, &xdpi))) {
 			dma_unmap_single(sq->pdev, xdpi.dma_addr,
 					 xdpf->len, DMA_TO_DEVICE);
 			xdp_return_frame_rx_napi(xdpf);
 			drops++;
 		}
 	}

 	if (flags & XDP_XMIT_FLUSH) {
 		if (sq->mpwqe.wqe)
 			mlx5e_xdp_mpwqe_complete(sq);
 		mlx5e_xmit_xdp_doorbell(sq);
 	}

 	return n - drops;
 }

 void mlx5e_xdp_rx_poll_complete(struct mlx5e_rq *rq)
 {
 	struct mlx5e_xdpsq *xdpsq = &rq->xdpsq;

 	if (xdpsq->mpwqe.wqe)
 		mlx5e_xdp_mpwqe_complete(xdpsq);

 	mlx5e_xmit_xdp_doorbell(xdpsq);

 	if (xdpsq->redirect_flush) {
 		xdp_do_flush_map();
 		xdpsq->redirect_flush = false;
 	}
 }

 void mlx5e_set_xmit_fp(struct mlx5e_xdpsq *sq, bool is_mpw)
 {
 	sq->xmit_xdp_frame = is_mpw ?
 		mlx5e_xmit_xdp_frame_mpwqe : mlx5e_xmit_xdp_frame;
 }
	/*
	* Copyright (c) 2018, Mellanox Technologies. All rights reserved.
	*
	* This software is available to you under a choice of one of two
	* licenses. You may choose to be licensed under the terms of the GNU
	* General Public License (GPL) Version 2, available from the file
	* COPYING in the main directory of this source tree, or the
	* OpenIB.org BSD license below:
	*
	* Redistribution and use in source and binary forms, with or
	* without modification, are permitted provided that the following
	* conditions are met:
	*
	* - Redistributions of source code must retain the above
	* copyright notice, this list of conditions and the following
	* disclaimer.
	*
	* - Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following
	* disclaimer in the documentation and/or other materials
	* provided with the distribution.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*/

	#include <linux/bpf_trace.h>
	#include "en/xdp.h"

	static inline bool
	mlx5e_xmit_xdp_buff(struct mlx5e_xdpsq sq, struct mlx5e_dma_info di,
	struct xdp_buff *xdp)
	{
	struct mlx5e_xdp_info xdpi;

	xdpi.xdpf = convert_to_xdp_frame(xdp);
	if (unlikely(!xdpi.xdpf))
	return false;
	xdpi.dma_addr = di->addr + (xdpi.xdpf->data - (void *)xdpi.xdpf);
	dma_sync_single_for_device(sq->pdev, xdpi.dma_addr,
	xdpi.xdpf->len, PCI_DMA_TODEVICE);
	xdpi.di = *di;

	return sq->xmit_xdp_frame(sq, &xdpi);
	}

	/* returns true if packet was consumed by xdp */
	bool mlx5e_xdp_handle(struct mlx5e_rq rq, struct mlx5e_dma_info di,
	void va, u16 rx_headroom, u32 *len)
	{
	struct bpf_prog *prog = READ_ONCE(rq->xdp_prog);
	struct xdp_buff xdp;
	u32 act;
	int err;

	if (!prog)
	return false;

	xdp.data = va + *rx_headroom;
	xdp_set_data_meta_invalid(&xdp);
	xdp.data_end = xdp.data + *len;
	xdp.data_hard_start = va;
	xdp.rxq = &rq->xdp_rxq;

	act = bpf_prog_run_xdp(prog, &xdp);
	switch (act) {
	case XDP_PASS:
	*rx_headroom = xdp.data - xdp.data_hard_start;
	*len = xdp.data_end - xdp.data;
	return false;
	case XDP_TX:
	if (unlikely(!mlx5e_xmit_xdp_buff(&rq->xdpsq, di, &xdp)))
	goto xdp_abort;
	__set_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags); /* non-atomic */
	return true;
	case XDP_REDIRECT:
	/* When XDP enabled then page-refcnt==1 here */
	err = xdp_do_redirect(rq->netdev, &xdp, prog);
	if (unlikely(err))
	goto xdp_abort;
	__set_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags);
	rq->xdpsq.redirect_flush = true;
	mlx5e_page_dma_unmap(rq, di);
	rq->stats->xdp_redirect++;
	return true;
	default:
	bpf_warn_invalid_xdp_action(act);
	/* fall through */
	case XDP_ABORTED:
	xdp_abort:
	trace_xdp_exception(rq->netdev, prog, act);
	/* fall through */
	case XDP_DROP:
	rq->stats->xdp_drop++;
	return true;
	}
	}

	static void mlx5e_xdp_mpwqe_session_start(struct mlx5e_xdpsq *sq)
	{
	struct mlx5e_xdp_mpwqe *session = &sq->mpwqe;
	struct mlx5_wq_cyc *wq = &sq->wq;
	u8 wqebbs;
	u16 pi;

	mlx5e_xdpsq_fetch_wqe(sq, &session->wqe);

	prefetchw(session->wqe->data);
	session->ds_count = MLX5E_XDP_TX_EMPTY_DS_COUNT;

	pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);

	/* The mult of MLX5_SEND_WQE_MAX_WQEBBS * MLX5_SEND_WQEBB_NUM_DS
	* (16 * 4 == 64) does not fit in the 6-bit DS field of Ctrl Segment.
	* We use a bound lower that MLX5_SEND_WQE_MAX_WQEBBS to let a
	* full-session WQE be cache-aligned.
	*/
	#if L1_CACHE_BYTES < 128
	#define MLX5E_XDP_MPW_MAX_WQEBBS (MLX5_SEND_WQE_MAX_WQEBBS - 1)
	#else
	#define MLX5E_XDP_MPW_MAX_WQEBBS (MLX5_SEND_WQE_MAX_WQEBBS - 2)
	#endif

	wqebbs = min_t(u16, mlx5_wq_cyc_get_contig_wqebbs(wq, pi),
	MLX5E_XDP_MPW_MAX_WQEBBS);

	session->max_ds_count = MLX5_SEND_WQEBB_NUM_DS * wqebbs;
	}

	static void mlx5e_xdp_mpwqe_complete(struct mlx5e_xdpsq *sq)
	{
	struct mlx5_wq_cyc *wq = &sq->wq;
	struct mlx5e_xdp_mpwqe *session = &sq->mpwqe;
	struct mlx5_wqe_ctrl_seg *cseg = &session->wqe->ctrl;
	u16 ds_count = session->ds_count;
	u16 pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);
	struct mlx5e_xdp_wqe_info *wi = &sq->db.wqe_info[pi];

	cseg->opmod_idx_opcode =
	cpu_to_be32((sq->pc << 8) \| MLX5_OPCODE_ENHANCED_MPSW);
	cseg->qpn_ds = cpu_to_be32((sq->sqn << 8) \| ds_count);

	wi->num_wqebbs = DIV_ROUND_UP(ds_count, MLX5_SEND_WQEBB_NUM_DS);
	wi->num_ds = ds_count - MLX5E_XDP_TX_EMPTY_DS_COUNT;

	sq->pc += wi->num_wqebbs;

	sq->doorbell_cseg = cseg;

	session->wqe = NULL; /* Close session */
	}

	static bool mlx5e_xmit_xdp_frame_mpwqe(struct mlx5e_xdpsq *sq,
	struct mlx5e_xdp_info *xdpi)
	{
	struct mlx5e_xdp_mpwqe *session = &sq->mpwqe;
	struct mlx5e_xdpsq_stats *stats = sq->stats;

	dma_addr_t dma_addr = xdpi->dma_addr;
	struct xdp_frame *xdpf = xdpi->xdpf;
	unsigned int dma_len = xdpf->len;

	if (unlikely(sq->hw_mtu < dma_len)) {
	stats->err++;
	return false;
	}

	if (unlikely(!session->wqe)) {
	if (unlikely(!mlx5e_wqc_has_room_for(&sq->wq, sq->cc, sq->pc,
	MLX5_SEND_WQE_MAX_WQEBBS))) {
	/* SQ is full, ring doorbell */
	mlx5e_xmit_xdp_doorbell(sq);
	stats->full++;
	return false;
	}

	mlx5e_xdp_mpwqe_session_start(sq);
	}

	mlx5e_xdp_mpwqe_add_dseg(sq, dma_addr, dma_len);

	if (unlikely(session->ds_count == session->max_ds_count))
	mlx5e_xdp_mpwqe_complete(sq);

	mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo, xdpi);
	stats->xmit++;
	return true;
	}

	static bool mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq sq, struct mlx5e_xdp_info xdpi)
	{
	struct mlx5_wq_cyc *wq = &sq->wq;
	u16 pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);
	struct mlx5e_tx_wqe *wqe = mlx5_wq_cyc_get_wqe(wq, pi);

	struct mlx5_wqe_ctrl_seg *cseg = &wqe->ctrl;
	struct mlx5_wqe_eth_seg *eseg = &wqe->eth;
	struct mlx5_wqe_data_seg *dseg = wqe->data;

	struct xdp_frame *xdpf = xdpi->xdpf;
	dma_addr_t dma_addr = xdpi->dma_addr;
	unsigned int dma_len = xdpf->len;

	struct mlx5e_xdpsq_stats *stats = sq->stats;

	prefetchw(wqe);

	if (unlikely(dma_len < MLX5E_XDP_MIN_INLINE \|\| sq->hw_mtu < dma_len)) {
	stats->err++;
	return false;
	}

	if (unlikely(!mlx5e_wqc_has_room_for(wq, sq->cc, sq->pc, 1))) {
	/* SQ is full, ring doorbell */
	mlx5e_xmit_xdp_doorbell(sq);
	stats->full++;
	return false;
	}

	cseg->fm_ce_se = 0;

	/* copy the inline part if required */
	if (sq->min_inline_mode != MLX5_INLINE_MODE_NONE) {
	memcpy(eseg->inline_hdr.start, xdpf->data, MLX5E_XDP_MIN_INLINE);
	eseg->inline_hdr.sz = cpu_to_be16(MLX5E_XDP_MIN_INLINE);
	dma_len -= MLX5E_XDP_MIN_INLINE;
	dma_addr += MLX5E_XDP_MIN_INLINE;
	dseg++;
	}

	/* write the dma part */
	dseg->addr = cpu_to_be64(dma_addr);
	dseg->byte_count = cpu_to_be32(dma_len);

	cseg->opmod_idx_opcode = cpu_to_be32((sq->pc << 8) \| MLX5_OPCODE_SEND);

	sq->pc++;

	sq->doorbell_cseg = cseg;

	mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo, xdpi);
	stats->xmit++;
	return true;
	}

	bool mlx5e_poll_xdpsq_cq(struct mlx5e_cq cq, struct mlx5e_rq rq)
	{
	struct mlx5e_xdp_info_fifo *xdpi_fifo;
	struct mlx5e_xdpsq *sq;
	struct mlx5_cqe64 *cqe;
	bool is_redirect;
	u16 sqcc;
	int i;

	sq = container_of(cq, struct mlx5e_xdpsq, cq);

	if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &sq->state)))
	return false;

	cqe = mlx5_cqwq_get_cqe(&cq->wq);
	if (!cqe)
	return false;

	is_redirect = !rq;
	xdpi_fifo = &sq->db.xdpi_fifo;

	/* sq->cc must be updated only after mlx5_cqwq_update_db_record(),
	* otherwise a cq overrun may occur
	*/
	sqcc = sq->cc;

	i = 0;
	do {
	u16 wqe_counter;
	bool last_wqe;

	mlx5_cqwq_pop(&cq->wq);

	wqe_counter = be16_to_cpu(cqe->wqe_counter);

	if (unlikely(get_cqe_opcode(cqe) != MLX5_CQE_REQ))
	netdev_WARN_ONCE(sq->channel->netdev,
	"Bad OP in XDPSQ CQE: 0x%x\n",
	get_cqe_opcode(cqe));

	do {
	struct mlx5e_xdp_wqe_info *wi;
	u16 ci, j;

	last_wqe = (sqcc == wqe_counter);
	ci = mlx5_wq_cyc_ctr2ix(&sq->wq, sqcc);
	wi = &sq->db.wqe_info[ci];

	sqcc += wi->num_wqebbs;

	for (j = 0; j < wi->num_ds; j++) {
	struct mlx5e_xdp_info xdpi =
	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);
	} else {
	/* Recycle RX page */
	mlx5e_page_release(rq, &xdpi.di, true);
	}
	}
	} while (!last_wqe);
	} while ((++i < MLX5E_TX_CQ_POLL_BUDGET) && (cqe = mlx5_cqwq_get_cqe(&cq->wq)));

	sq->stats->cqes += i;

	mlx5_cqwq_update_db_record(&cq->wq);

	/* ensure cq space is freed before enabling more cqes */
	wmb();

	sq->cc = sqcc;
	return (i == MLX5E_TX_CQ_POLL_BUDGET);
	}

	void mlx5e_free_xdpsq_descs(struct mlx5e_xdpsq sq, struct mlx5e_rq rq)
	{
	struct mlx5e_xdp_info_fifo *xdpi_fifo = &sq->db.xdpi_fifo;
	bool is_redirect = !rq;

	while (sq->cc != sq->pc) {
	struct mlx5e_xdp_wqe_info *wi;
	u16 ci, i;

	ci = mlx5_wq_cyc_ctr2ix(&sq->wq, sq->cc);
	wi = &sq->db.wqe_info[ci];

	sq->cc += wi->num_wqebbs;

	for (i = 0; i < wi->num_ds; i++) {
	struct mlx5e_xdp_info xdpi =
	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);
	} else {
	/* Recycle RX page */
	mlx5e_page_release(rq, &xdpi.di, false);
	}
	}
	}
	}

	int mlx5e_xdp_xmit(struct net_device dev, int n, struct xdp_frame *frames,
	u32 flags)
	{
	struct mlx5e_priv *priv = netdev_priv(dev);
	struct mlx5e_xdpsq *sq;
	int drops = 0;
	int sq_num;
	int i;

	/* this flag is sufficient, no need to test internal sq state */
	if (unlikely(!mlx5e_xdp_tx_is_enabled(priv)))
	return -ENETDOWN;

	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
	return -EINVAL;

	sq_num = smp_processor_id();

	if (unlikely(sq_num >= priv->channels.num))
	return -ENXIO;

	sq = &priv->channels.c[sq_num]->xdpsq;

	for (i = 0; i < n; i++) {
	struct xdp_frame *xdpf = frames[i];
	struct mlx5e_xdp_info xdpi;

	xdpi.dma_addr = dma_map_single(sq->pdev, xdpf->data, xdpf->len,
	DMA_TO_DEVICE);
	if (unlikely(dma_mapping_error(sq->pdev, xdpi.dma_addr))) {
	xdp_return_frame_rx_napi(xdpf);
	drops++;
	continue;
	}

	xdpi.xdpf = xdpf;

	if (unlikely(!sq->xmit_xdp_frame(sq, &xdpi))) {
	dma_unmap_single(sq->pdev, xdpi.dma_addr,
	xdpf->len, DMA_TO_DEVICE);
	xdp_return_frame_rx_napi(xdpf);
	drops++;
	}
	}

	if (flags & XDP_XMIT_FLUSH) {
	if (sq->mpwqe.wqe)
	mlx5e_xdp_mpwqe_complete(sq);
	mlx5e_xmit_xdp_doorbell(sq);
	}

	return n - drops;
	}

	void mlx5e_xdp_rx_poll_complete(struct mlx5e_rq *rq)
	{
	struct mlx5e_xdpsq *xdpsq = &rq->xdpsq;

	if (xdpsq->mpwqe.wqe)
	mlx5e_xdp_mpwqe_complete(xdpsq);

	mlx5e_xmit_xdp_doorbell(xdpsq);

	if (xdpsq->redirect_flush) {
	xdp_do_flush_map();
	xdpsq->redirect_flush = false;
	}
	}

	void mlx5e_set_xmit_fp(struct mlx5e_xdpsq *sq, bool is_mpw)
	{
	sq->xmit_xdp_frame = is_mpw ?
	mlx5e_xmit_xdp_frame_mpwqe : mlx5e_xmit_xdp_frame;
	}