Commit 1aea9d87 authored by Lorenzo Bianconi's avatar Lorenzo Bianconi Committed by Jakub Kicinski
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igb: add xdp frags support to ndo_xdp_xmit 



Add the capability to map non-linear xdp frames in XDP_TX and
ndo_xdp_xmit callback.

Signed-off-by: default avatarLorenzo Bianconi <lorenzo@kernel.org>
Tested-by: Chandan Kumar Rout <chandanx.rout@intel.com> (A Contingent worker at Intel)
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
Link: https://lore.kernel.org/r/20220711230751.3124415-1-anthony.l.nguyen@intel.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent c9ef2a48

drivers/net/ethernet/intel/igb/igb_main.c

+78 −43
Original line number Diff line number Diff line
@@ -6260,74 +6260,108 @@ int igb_xmit_xdp_ring(struct igb_adapter *adapter, 
		      struct igb_ring *tx_ring,

		      struct xdp_frame *xdpf)

{

	union e1000_adv_tx_desc *tx_desc;

	u32 len, cmd_type, olinfo_status;

	struct igb_tx_buffer *tx_buffer;

	dma_addr_t dma;

	u16 i;



	len = xdpf->len;



	if (unlikely(!igb_desc_unused(tx_ring)))

		return IGB_XDP_CONSUMED;



	dma = dma_map_single(tx_ring->dev, xdpf->data, len, DMA_TO_DEVICE);

	if (dma_mapping_error(tx_ring->dev, dma))

	struct skb_shared_info *sinfo = xdp_get_shared_info_from_frame(xdpf);

	u8 nr_frags = unlikely(xdp_frame_has_frags(xdpf)) ? sinfo->nr_frags : 0;

	u16 count, i, index = tx_ring->next_to_use;

	struct igb_tx_buffer *tx_head = &tx_ring->tx_buffer_info[index];

	struct igb_tx_buffer *tx_buffer = tx_head;

	union e1000_adv_tx_desc *tx_desc = IGB_TX_DESC(tx_ring, index);

	u32 len = xdpf->len, cmd_type, olinfo_status;

	void *data = xdpf->data;



	count = TXD_USE_COUNT(len);

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

		count += TXD_USE_COUNT(skb_frag_size(&sinfo->frags[i]));



	if (igb_maybe_stop_tx(tx_ring, count + 3))

		return IGB_XDP_CONSUMED;



	i = 0;

	/* record the location of the first descriptor for this packet */

	tx_buffer = &tx_ring->tx_buffer_info[tx_ring->next_to_use];

	tx_buffer->bytecount = len;

	tx_buffer->gso_segs = 1;

	tx_buffer->protocol = 0;

	tx_head->bytecount = xdp_get_frame_len(xdpf);

	tx_head->type = IGB_TYPE_XDP;

	tx_head->gso_segs = 1;

	tx_head->xdpf = xdpf;



	i = tx_ring->next_to_use;

	tx_desc = IGB_TX_DESC(tx_ring, i);

	olinfo_status = tx_head->bytecount << E1000_ADVTXD_PAYLEN_SHIFT;

	/* 82575 requires a unique index per ring */

	if (test_bit(IGB_RING_FLAG_TX_CTX_IDX, &tx_ring->flags))

		olinfo_status |= tx_ring->reg_idx << 4;

	tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status);



	for (;;) {

		dma_addr_t dma;



		dma = dma_map_single(tx_ring->dev, data, len, DMA_TO_DEVICE);

		if (dma_mapping_error(tx_ring->dev, dma))

			goto unmap;



		/* record length, and DMA address */

		dma_unmap_len_set(tx_buffer, len, len);

		dma_unmap_addr_set(tx_buffer, dma, dma);

	tx_buffer->type = IGB_TYPE_XDP;

	tx_buffer->xdpf = xdpf;



	tx_desc->read.buffer_addr = cpu_to_le64(dma);



		/* put descriptor type bits */

	cmd_type = E1000_ADVTXD_DTYP_DATA |

		   E1000_ADVTXD_DCMD_DEXT |

		   E1000_ADVTXD_DCMD_IFCS;

	cmd_type |= len | IGB_TXD_DCMD;

		cmd_type = E1000_ADVTXD_DTYP_DATA | E1000_ADVTXD_DCMD_DEXT |

			   E1000_ADVTXD_DCMD_IFCS | len;



		tx_desc->read.cmd_type_len = cpu_to_le32(cmd_type);

		tx_desc->read.buffer_addr = cpu_to_le64(dma);



	olinfo_status = len << E1000_ADVTXD_PAYLEN_SHIFT;

	/* 82575 requires a unique index per ring */

	if (test_bit(IGB_RING_FLAG_TX_CTX_IDX, &tx_ring->flags))

		olinfo_status |= tx_ring->reg_idx << 4;

		tx_buffer->protocol = 0;



	tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status);

		if (++index == tx_ring->count)

			index = 0;



		if (i == nr_frags)

			break;



		tx_buffer = &tx_ring->tx_buffer_info[index];

		tx_desc = IGB_TX_DESC(tx_ring, index);

		tx_desc->read.olinfo_status = 0;



	netdev_tx_sent_queue(txring_txq(tx_ring), tx_buffer->bytecount);

		data = skb_frag_address(&sinfo->frags[i]);

		len = skb_frag_size(&sinfo->frags[i]);

		i++;

	}

	tx_desc->read.cmd_type_len |= cpu_to_le32(IGB_TXD_DCMD);



	netdev_tx_sent_queue(txring_txq(tx_ring), tx_head->bytecount);

	/* set the timestamp */

	tx_buffer->time_stamp = jiffies;

	tx_head->time_stamp = jiffies;



	/* Avoid any potential race with xdp_xmit and cleanup */

	smp_wmb();



	/* set next_to_watch value indicating a packet is present */

	i++;

	if (i == tx_ring->count)

		i = 0;



	tx_buffer->next_to_watch = tx_desc;

	tx_ring->next_to_use = i;

	tx_head->next_to_watch = tx_desc;

	tx_ring->next_to_use = index;



	/* Make sure there is space in the ring for the next send. */

	igb_maybe_stop_tx(tx_ring, DESC_NEEDED);



	if (netif_xmit_stopped(txring_txq(tx_ring)) || !netdev_xmit_more())

		writel(i, tx_ring->tail);

		writel(index, tx_ring->tail);



	return IGB_XDP_TX;



unmap:

	for (;;) {

		tx_buffer = &tx_ring->tx_buffer_info[index];

		if (dma_unmap_len(tx_buffer, len))

			dma_unmap_page(tx_ring->dev,

				       dma_unmap_addr(tx_buffer, dma),

				       dma_unmap_len(tx_buffer, len),

				       DMA_TO_DEVICE);

		dma_unmap_len_set(tx_buffer, len, 0);

		if (tx_buffer == tx_head)

			break;



		if (!index)

			index += tx_ring->count;

		index--;

	}



	return IGB_XDP_CONSUMED;

}



netdev_tx_t igb_xmit_frame_ring(struct sk_buff *skb,
@@ -8818,6 +8852,7 @@ static int igb_clean_rx_irq(struct igb_q_vector *q_vector, const int budget) 
			unsigned int offset = pkt_offset + igb_rx_offset(rx_ring);



			xdp_prepare_buff(&xdp, hard_start, offset, size, true);

			xdp_buff_clear_frags_flag(&xdp);

#if (PAGE_SIZE > 4096)

			/* At larger PAGE_SIZE, frame_sz depend on len size */

			xdp.frame_sz = igb_rx_frame_truesize(rx_ring, size);