Commit 73b7123d authored by Jesper Dangaard Brouer's avatar Jesper Dangaard Brouer Committed by Daniel Borkmann
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igc: Add igc_xdp_buff wrapper for xdp_buff in driver 



Driver specific metadata data for XDP-hints kfuncs are propagated via tail
extending the struct xdp_buff with a locally scoped driver struct.

Zero-Copy AF_XDP/XSK does similar tricks via struct xdp_buff_xsk. This
xdp_buff_xsk struct contains a CB area (24 bytes) that can be used for
extending the locally scoped driver into. The XSK_CHECK_PRIV_TYPE define
catch size violations build time.

The changes needed for AF_XDP zero-copy in igc_clean_rx_irq_zc()
is done in next patch, because the member rx_desc isn't available
at this point.

Signed-off-by: default avatarJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarSong Yoong Siang <yoong.siang.song@intel.com>
Link: https://lore.kernel.org/bpf/168182464779.616355.3761989884165609387.stgit@firesoul
parent 84214ab4

drivers/net/ethernet/intel/igc/igc.h

+5 −0
Original line number Diff line number Diff line
@@ -499,6 +499,11 @@ struct igc_rx_buffer { 
	};

};



/* context wrapper around xdp_buff to provide access to descriptor metadata */

struct igc_xdp_buff {

	struct xdp_buff xdp;

};



struct igc_q_vector {

	struct igc_adapter *adapter;    /* backlink */

	void __iomem *itr_register;

drivers/net/ethernet/intel/igc/igc_main.c

+9 −7
Original line number Diff line number Diff line
@@ -2233,6 +2233,8 @@ static bool igc_alloc_rx_buffers_zc(struct igc_ring *ring, u16 count) 
	if (!count)

		return ok;



	XSK_CHECK_PRIV_TYPE(struct igc_xdp_buff);



	desc = IGC_RX_DESC(ring, i);

	bi = &ring->rx_buffer_info[i];

	i -= ring->count;
@@ -2517,8 +2519,8 @@ static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) 
		union igc_adv_rx_desc *rx_desc;

		struct igc_rx_buffer *rx_buffer;

		unsigned int size, truesize;

		struct igc_xdp_buff ctx;

		ktime_t timestamp = 0;

		struct xdp_buff xdp;

		int pkt_offset = 0;

		void *pktbuf;
@@ -2552,13 +2554,13 @@ static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) 
		}



		if (!skb) {

			xdp_init_buff(&xdp, truesize, &rx_ring->xdp_rxq);

			xdp_prepare_buff(&xdp, pktbuf - igc_rx_offset(rx_ring),

			xdp_init_buff(&ctx.xdp, truesize, &rx_ring->xdp_rxq);

			xdp_prepare_buff(&ctx.xdp, pktbuf - igc_rx_offset(rx_ring),

					 igc_rx_offset(rx_ring) + pkt_offset,

					 size, true);

			xdp_buff_clear_frags_flag(&xdp);

			xdp_buff_clear_frags_flag(&ctx.xdp);



			skb = igc_xdp_run_prog(adapter, &xdp);

			skb = igc_xdp_run_prog(adapter, &ctx.xdp);

		}



		if (IS_ERR(skb)) {
@@ -2580,9 +2582,9 @@ static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget) 
		} else if (skb)

			igc_add_rx_frag(rx_ring, rx_buffer, skb, size);

		else if (ring_uses_build_skb(rx_ring))

			skb = igc_build_skb(rx_ring, rx_buffer, &xdp);

			skb = igc_build_skb(rx_ring, rx_buffer, &ctx.xdp);

		else

			skb = igc_construct_skb(rx_ring, rx_buffer, &xdp,

			skb = igc_construct_skb(rx_ring, rx_buffer, &ctx.xdp,

						timestamp);



		/* exit if we failed to retrieve a buffer */