Commit 6d6b39f1 authored by Shenwei Wang's avatar Shenwei Wang Committed by Paolo Abeni
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net: fec: add initial XDP support 



This patch adds the initial XDP support to Freescale driver. It supports
XDP_PASS, XDP_DROP and XDP_REDIRECT actions. Upcoming patches will add
support for XDP_TX and Zero Copy features.

As the patch is rather large, the part of codes to collect the
statistics is separated and will prepare a dedicated patch for that
part.

I just tested with the application of xdpsock.
  -- Native here means running command of "xdpsock -i eth0"
  -- SKB-Mode means running command of "xdpsock -S -i eth0"

The following are the testing result relating to XDP mode:

root@imx8qxpc0mek:~/bpf# ./xdpsock -i eth0
 sock0@eth0:0 rxdrop xdp-drv
                   pps            pkts           1.00
rx                 371347         2717794
tx                 0              0

root@imx8qxpc0mek:~/bpf# ./xdpsock -S -i eth0
 sock0@eth0:0 rxdrop xdp-skb
                   pps            pkts           1.00
rx                 202229         404528
tx                 0              0

root@imx8qxpc0mek:~/bpf# ./xdp2 eth0
proto 0:     496708 pkt/s
proto 0:     505469 pkt/s
proto 0:     505283 pkt/s
proto 0:     505443 pkt/s
proto 0:     505465 pkt/s

root@imx8qxpc0mek:~/bpf# ./xdp2 -S eth0
proto 0:          0 pkt/s
proto 17:     118778 pkt/s
proto 17:     118989 pkt/s
proto 0:          1 pkt/s
proto 17:     118987 pkt/s
proto 0:          0 pkt/s
proto 17:     118943 pkt/s
proto 17:     118976 pkt/s
proto 0:          1 pkt/s
proto 17:     119006 pkt/s
proto 0:          0 pkt/s
proto 17:     119071 pkt/s
proto 17:     119092 pkt/s

Signed-off-by: default avatarShenwei Wang <shenwei.wang@nxp.com>
Reported-by: default avatarkernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20221031185350.2045675-1-shenwei.wang@nxp.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 598d2982

drivers/net/ethernet/freescale/fec.h

+3 −1
Original line number Diff line number Diff line
@@ -348,7 +348,6 @@ struct bufdesc_ex { 
 */



#define FEC_ENET_XDP_HEADROOM	(XDP_PACKET_HEADROOM)



#define FEC_ENET_RX_PAGES	256

#define FEC_ENET_RX_FRSIZE	(PAGE_SIZE - FEC_ENET_XDP_HEADROOM \

		- SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
@@ -663,6 +662,9 @@ struct fec_enet_private { 


	struct imx_sc_ipc *ipc_handle;



	/* XDP BPF Program */

	struct bpf_prog *xdp_prog;



	u64 ethtool_stats[];

};

drivers/net/ethernet/freescale/fec_main.c

+223 −1
Original line number Diff line number Diff line
@@ -89,6 +89,11 @@ static const u16 fec_enet_vlan_pri_to_queue[8] = {0, 0, 1, 1, 1, 2, 2, 2}; 
#define FEC_ENET_OPD_V	0xFFF0

#define FEC_MDIO_PM_TIMEOUT  100 /* ms */



#define FEC_ENET_XDP_PASS          0

#define FEC_ENET_XDP_CONSUMED      BIT(0)

#define FEC_ENET_XDP_TX            BIT(1)

#define FEC_ENET_XDP_REDIR         BIT(2)



struct fec_devinfo {

	u32 quirks;

};
@@ -418,13 +423,14 @@ static int 
fec_enet_create_page_pool(struct fec_enet_private *fep,

			  struct fec_enet_priv_rx_q *rxq, int size)

{

	struct bpf_prog *xdp_prog = READ_ONCE(fep->xdp_prog);

	struct page_pool_params pp_params = {

		.order = 0,

		.flags = PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV,

		.pool_size = size,

		.nid = dev_to_node(&fep->pdev->dev),

		.dev = &fep->pdev->dev,

		.dma_dir = DMA_FROM_DEVICE,

		.dma_dir = xdp_prog ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE,

		.offset = FEC_ENET_XDP_HEADROOM,

		.max_len = FEC_ENET_RX_FRSIZE,

	};
@@ -1499,6 +1505,59 @@ static void fec_enet_update_cbd(struct fec_enet_priv_rx_q *rxq, 
	bdp->cbd_bufaddr = cpu_to_fec32(phys_addr);

}



static u32

fec_enet_run_xdp(struct fec_enet_private *fep, struct bpf_prog *prog,

		 struct xdp_buff *xdp, struct fec_enet_priv_rx_q *rxq, int index)

{

	unsigned int sync, len = xdp->data_end - xdp->data;

	u32 ret = FEC_ENET_XDP_PASS;

	struct page *page;

	int err;

	u32 act;



	act = bpf_prog_run_xdp(prog, xdp);



	/* Due xdp_adjust_tail: DMA sync for_device cover max len CPU touch */

	sync = xdp->data_end - xdp->data_hard_start - FEC_ENET_XDP_HEADROOM;

	sync = max(sync, len);



	switch (act) {

	case XDP_PASS:

		ret = FEC_ENET_XDP_PASS;

		break;



	case XDP_REDIRECT:

		err = xdp_do_redirect(fep->netdev, xdp, prog);

		if (!err) {

			ret = FEC_ENET_XDP_REDIR;

		} else {

			ret = FEC_ENET_XDP_CONSUMED;

			page = virt_to_head_page(xdp->data);

			page_pool_put_page(rxq->page_pool, page, sync, true);

		}

		break;



	default:

		bpf_warn_invalid_xdp_action(fep->netdev, prog, act);

		fallthrough;



	case XDP_TX:

		bpf_warn_invalid_xdp_action(fep->netdev, prog, act);

		fallthrough;



	case XDP_ABORTED:

		fallthrough;    /* handle aborts by dropping packet */



	case XDP_DROP:

		ret = FEC_ENET_XDP_CONSUMED;

		page = virt_to_head_page(xdp->data);

		page_pool_put_page(rxq->page_pool, page, sync, true);

		break;

	}



	return ret;

}



/* During a receive, the bd_rx.cur points to the current incoming buffer.

 * When we update through the ring, if the next incoming buffer has

 * not been given to the system, we just set the empty indicator,
@@ -1520,6 +1579,9 @@ fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id) 
	u16	vlan_tag;

	int	index = 0;

	bool	need_swap = fep->quirks & FEC_QUIRK_SWAP_FRAME;

	struct bpf_prog *xdp_prog = READ_ONCE(fep->xdp_prog);

	u32 ret, xdp_result = FEC_ENET_XDP_PASS;

	struct xdp_buff xdp;

	struct page *page;



#ifdef CONFIG_M532x
@@ -1531,6 +1593,7 @@ fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id) 
	 * These get messed up if we get called due to a busy condition.

	 */

	bdp = rxq->bd.cur;

	xdp_init_buff(&xdp, PAGE_SIZE, &rxq->xdp_rxq);



	while (!((status = fec16_to_cpu(bdp->cbd_sc)) & BD_ENET_RX_EMPTY)) {
@@ -1580,6 +1643,17 @@ fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id) 
		prefetch(page_address(page));

		fec_enet_update_cbd(rxq, bdp, index);



		if (xdp_prog) {

			xdp_buff_clear_frags_flag(&xdp);

			xdp_prepare_buff(&xdp, page_address(page),

					 FEC_ENET_XDP_HEADROOM, pkt_len, false);



			ret = fec_enet_run_xdp(fep, xdp_prog, &xdp, rxq, index);

			xdp_result |= ret;

			if (ret != FEC_ENET_XDP_PASS)

				goto rx_processing_done;

		}



		/* The packet length includes FCS, but we don't want to

		 * include that when passing upstream as it messes up

		 * bridging applications.
@@ -1675,6 +1749,10 @@ fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id) 
		writel(0, rxq->bd.reg_desc_active);

	}

	rxq->bd.cur = bdp;



	if (xdp_result & FEC_ENET_XDP_REDIR)

		xdp_do_flush_map();



	return pkt_received;

}
@@ -3518,6 +3596,148 @@ static u16 fec_enet_select_queue(struct net_device *ndev, struct sk_buff *skb, 
	return fec_enet_vlan_pri_to_queue[vlan_tag >> 13];

}



static int fec_enet_bpf(struct net_device *dev, struct netdev_bpf *bpf)

{

	struct fec_enet_private *fep = netdev_priv(dev);

	bool is_run = netif_running(dev);

	struct bpf_prog *old_prog;



	switch (bpf->command) {

	case XDP_SETUP_PROG:

		if (is_run) {

			napi_disable(&fep->napi);

			netif_tx_disable(dev);

		}



		old_prog = xchg(&fep->xdp_prog, bpf->prog);

		fec_restart(dev);



		if (is_run) {

			napi_enable(&fep->napi);

			netif_tx_start_all_queues(dev);

		}



		if (old_prog)

			bpf_prog_put(old_prog);



		return 0;



	case XDP_SETUP_XSK_POOL:

		return -EOPNOTSUPP;



	default:

		return -EOPNOTSUPP;

	}

}



static int

fec_enet_xdp_get_tx_queue(struct fec_enet_private *fep, int cpu)

{

	int index = cpu;



	if (unlikely(index < 0))

		index = 0;



	while (index >= fep->num_tx_queues)

		index -= fep->num_tx_queues;



	return index;

}



static int fec_enet_txq_xmit_frame(struct fec_enet_private *fep,

				   struct fec_enet_priv_tx_q *txq,

				   struct xdp_frame *frame)

{

	unsigned int index, status, estatus;

	struct bufdesc *bdp, *last_bdp;

	dma_addr_t dma_addr;

	int entries_free;



	entries_free = fec_enet_get_free_txdesc_num(txq);

	if (entries_free < MAX_SKB_FRAGS + 1) {

		netdev_err(fep->netdev, "NOT enough BD for SG!\n");

		return NETDEV_TX_OK;

	}



	/* Fill in a Tx ring entry */

	bdp = txq->bd.cur;

	last_bdp = bdp;

	status = fec16_to_cpu(bdp->cbd_sc);

	status &= ~BD_ENET_TX_STATS;



	index = fec_enet_get_bd_index(bdp, &txq->bd);



	dma_addr = dma_map_single(&fep->pdev->dev, frame->data,

				  frame->len, DMA_TO_DEVICE);

	if (dma_mapping_error(&fep->pdev->dev, dma_addr))

		return FEC_ENET_XDP_CONSUMED;



	status |= (BD_ENET_TX_INTR | BD_ENET_TX_LAST);

	if (fep->bufdesc_ex)

		estatus = BD_ENET_TX_INT;



	bdp->cbd_bufaddr = cpu_to_fec32(dma_addr);

	bdp->cbd_datlen = cpu_to_fec16(frame->len);



	if (fep->bufdesc_ex) {

		struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp;



		if (fep->quirks & FEC_QUIRK_HAS_AVB)

			estatus |= FEC_TX_BD_FTYPE(txq->bd.qid);



		ebdp->cbd_bdu = 0;

		ebdp->cbd_esc = cpu_to_fec32(estatus);

	}



	index = fec_enet_get_bd_index(last_bdp, &txq->bd);

	txq->tx_skbuff[index] = NULL;



	/* Send it on its way.  Tell FEC it's ready, interrupt when done,

	 * it's the last BD of the frame, and to put the CRC on the end.

	 */

	status |= (BD_ENET_TX_READY | BD_ENET_TX_TC);

	bdp->cbd_sc = cpu_to_fec16(status);



	/* If this was the last BD in the ring, start at the beginning again. */

	bdp = fec_enet_get_nextdesc(last_bdp, &txq->bd);



	txq->bd.cur = bdp;



	return 0;

}



static int fec_enet_xdp_xmit(struct net_device *dev,

			     int num_frames,

			     struct xdp_frame **frames,

			     u32 flags)

{

	struct fec_enet_private *fep = netdev_priv(dev);

	struct fec_enet_priv_tx_q *txq;

	int cpu = smp_processor_id();

	struct netdev_queue *nq;

	unsigned int queue;

	int i;



	queue = fec_enet_xdp_get_tx_queue(fep, cpu);

	txq = fep->tx_queue[queue];

	nq = netdev_get_tx_queue(fep->netdev, queue);



	__netif_tx_lock(nq, cpu);



	for (i = 0; i < num_frames; i++)

		fec_enet_txq_xmit_frame(fep, txq, frames[i]);



	/* Make sure the update to bdp and tx_skbuff are performed. */

	wmb();



	/* Trigger transmission start */

	writel(0, txq->bd.reg_desc_active);



	__netif_tx_unlock(nq);



	return num_frames;

}



static const struct net_device_ops fec_netdev_ops = {

	.ndo_open		= fec_enet_open,

	.ndo_stop		= fec_enet_close,
@@ -3532,6 +3752,8 @@ static const struct net_device_ops fec_netdev_ops = { 
	.ndo_poll_controller	= fec_poll_controller,

#endif

	.ndo_set_features	= fec_set_features,

	.ndo_bpf		= fec_enet_bpf,

	.ndo_xdp_xmit		= fec_enet_xdp_xmit,

};



static const unsigned short offset_des_active_rxq[] = {