Commit a7559bc8 authored by Andy Gospodarek's avatar Andy Gospodarek Committed by David S. Miller
Browse files

bnxt: support transmit and free of aggregation buffers 



This patch adds the following features:
- Support for XDP_TX and XDP_DROP action when using xdp_buff
  with frags
- Support for freeing all frags attached to an xdp_buff
- Cleanup of TX ring buffers after transmits complete
- Slight change in definition of bnxt_sw_tx_bd since nr_frags
  and RX producer may both need to be used
- Clear out skb_shared_info at the end of the buffer

v2: Fix uninitialized variable warning in bnxt_xdp_buff_frags_free().

Signed-off-by: default avatarAndy Gospodarek <gospo@broadcom.com>
Signed-off-by: default avatarMichael Chan <michael.chan@broadcom.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1dc4c557

drivers/net/ethernet/broadcom/bnxt/bnxt.c

+13 −5
Original line number Diff line number Diff line
@@ -1951,9 +1951,13 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_cp_ring_info *cpr, 
		skb = bnxt_copy_skb(bnapi, data_ptr, len, dma_addr);

		bnxt_reuse_rx_data(rxr, cons, data);

		if (!skb) {

			if (agg_bufs)

			if (agg_bufs) {

				if (!xdp_active)

					bnxt_reuse_rx_agg_bufs(cpr, cp_cons, 0,

							       agg_bufs, false);

				else

					bnxt_xdp_buff_frags_free(rxr, &xdp);

			}

			cpr->sw_stats.rx.rx_oom_discards += 1;

			rc = -ENOMEM;

			goto next_rx;
@@ -1986,6 +1990,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_cp_ring_info *cpr, 
			skb = bnxt_xdp_build_skb(bp, skb, agg_bufs, rxr->page_pool, &xdp, rxcmp1);

			if (!skb) {

				/* we should be able to free the old skb here */

				bnxt_xdp_buff_frags_free(rxr, &xdp);

				cpr->sw_stats.rx.rx_oom_discards += 1;

				rc = -ENOMEM;

				goto next_rx;
@@ -2605,10 +2610,13 @@ static void __bnxt_poll_work_done(struct bnxt *bp, struct bnxt_napi *bnapi) 
	if ((bnapi->events & BNXT_RX_EVENT) && !(bnapi->in_reset)) {

		struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;



		if (bnapi->events & BNXT_AGG_EVENT)

			bnxt_db_write(bp, &rxr->rx_agg_db, rxr->rx_agg_prod);

		bnxt_db_write(bp, &rxr->rx_db, rxr->rx_prod);

	}

	if (bnapi->events & BNXT_AGG_EVENT) {

		struct bnxt_rx_ring_info *rxr = bnapi->rx_ring;



		bnxt_db_write(bp, &rxr->rx_agg_db, rxr->rx_agg_prod);

	}

	bnapi->events = 0;

}

drivers/net/ethernet/broadcom/bnxt/bnxt.h

+3 −4
Original line number Diff line number Diff line
@@ -701,14 +701,13 @@ struct bnxt_sw_tx_bd { 
	};

	DEFINE_DMA_UNMAP_ADDR(mapping);

	DEFINE_DMA_UNMAP_LEN(len);

	struct page		*page;

	u8			is_gso;

	u8			is_push;

	u8			action;

	union {

	unsigned short		nr_frags;

	u16			rx_prod;

};

};



struct bnxt_sw_rx_bd {

	void			*data;

drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c

+1 −1
Original line number Diff line number Diff line
@@ -3491,7 +3491,7 @@ static int bnxt_run_loopback(struct bnxt *bp) 
		dev_kfree_skb(skb);

		return -EIO;

	}

	bnxt_xmit_bd(bp, txr, map, pkt_size);

	bnxt_xmit_bd(bp, txr, map, pkt_size, NULL);



	/* Sync BD data before updating doorbell */

	wmb();

drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c

+105 −12
Original line number Diff line number Diff line
@@ -24,36 +24,91 @@ DEFINE_STATIC_KEY_FALSE(bnxt_xdp_locking_key); 


struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp,

				   struct bnxt_tx_ring_info *txr,

				   dma_addr_t mapping, u32 len)

				   dma_addr_t mapping, u32 len,

				   struct xdp_buff *xdp)

{

	struct bnxt_sw_tx_bd *tx_buf;

	struct skb_shared_info *sinfo;

	struct bnxt_sw_tx_bd *tx_buf, *first_buf;

	struct tx_bd *txbd;

	int num_frags = 0;

	u32 flags;

	u16 prod;

	int i;



	if (xdp && xdp_buff_has_frags(xdp)) {

		sinfo = xdp_get_shared_info_from_buff(xdp);

		num_frags = sinfo->nr_frags;

	}



	/* fill up the first buffer */

	prod = txr->tx_prod;

	tx_buf = &txr->tx_buf_ring[prod];

	first_buf = tx_buf;

	tx_buf->nr_frags = num_frags;

	if (xdp)

		tx_buf->page = virt_to_head_page(xdp->data);



	txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)];

	flags = (len << TX_BD_LEN_SHIFT) | (1 << TX_BD_FLAGS_BD_CNT_SHIFT) |

		TX_BD_FLAGS_PACKET_END | bnxt_lhint_arr[len >> 9];

	flags = ((len) << TX_BD_LEN_SHIFT) | ((num_frags + 1) << TX_BD_FLAGS_BD_CNT_SHIFT);

	txbd->tx_bd_len_flags_type = cpu_to_le32(flags);

	txbd->tx_bd_opaque = prod;

	txbd->tx_bd_haddr = cpu_to_le64(mapping);



	/* now let us fill up the frags into the next buffers */

	for (i = 0; i < num_frags ; i++) {

		skb_frag_t *frag = &sinfo->frags[i];

		struct bnxt_sw_tx_bd *frag_tx_buf;

		struct pci_dev *pdev = bp->pdev;

		dma_addr_t frag_mapping;

		int frag_len;



		prod = NEXT_TX(prod);

		txr->tx_prod = prod;



		/* first fill up the first buffer */

		frag_tx_buf = &txr->tx_buf_ring[prod];

		frag_tx_buf->page = skb_frag_page(frag);



		txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)];



		frag_len = skb_frag_size(frag);

		frag_mapping = skb_frag_dma_map(&pdev->dev, frag, 0,

						frag_len, DMA_TO_DEVICE);



		if (unlikely(dma_mapping_error(&pdev->dev, frag_mapping)))

			return NULL;



		dma_unmap_addr_set(frag_tx_buf, mapping, frag_mapping);



		flags = frag_len << TX_BD_LEN_SHIFT;

		txbd->tx_bd_len_flags_type = cpu_to_le32(flags);

		txbd->tx_bd_opaque = prod;

		txbd->tx_bd_haddr = cpu_to_le64(frag_mapping);



		len = frag_len;

	}



	flags &= ~TX_BD_LEN;

	txbd->tx_bd_len_flags_type = cpu_to_le32(((len) << TX_BD_LEN_SHIFT) | flags |

			TX_BD_FLAGS_PACKET_END);

	/* Sync TX BD */

	wmb();

	prod = NEXT_TX(prod);

	txr->tx_prod = prod;

	return tx_buf;



	return first_buf;

}



static void __bnxt_xmit_xdp(struct bnxt *bp, struct bnxt_tx_ring_info *txr,

			    dma_addr_t mapping, u32 len, u16 rx_prod)

			    dma_addr_t mapping, u32 len, u16 rx_prod,

			    struct xdp_buff *xdp)

{

	struct bnxt_sw_tx_bd *tx_buf;



	tx_buf = bnxt_xmit_bd(bp, txr, mapping, len);

	tx_buf = bnxt_xmit_bd(bp, txr, mapping, len, xdp);

	tx_buf->rx_prod = rx_prod;

	tx_buf->action = XDP_TX;



}



static void __bnxt_xmit_xdp_redirect(struct bnxt *bp,
@@ -63,7 +118,7 @@ static void __bnxt_xmit_xdp_redirect(struct bnxt *bp, 
{

	struct bnxt_sw_tx_bd *tx_buf;



	tx_buf = bnxt_xmit_bd(bp, txr, mapping, len);

	tx_buf = bnxt_xmit_bd(bp, txr, mapping, len, NULL);

	tx_buf->action = XDP_REDIRECT;

	tx_buf->xdpf = xdpf;

	dma_unmap_addr_set(tx_buf, mapping, mapping);
@@ -78,7 +133,7 @@ void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) 
	struct bnxt_sw_tx_bd *tx_buf;

	u16 tx_cons = txr->tx_cons;

	u16 last_tx_cons = tx_cons;

	int i;

	int i, j, frags;



	for (i = 0; i < nr_pkts; i++) {

		tx_buf = &txr->tx_buf_ring[tx_cons];
@@ -96,6 +151,13 @@ void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) 
		} else if (tx_buf->action == XDP_TX) {

			rx_doorbell_needed = true;

			last_tx_cons = tx_cons;



			frags = tx_buf->nr_frags;

			for (j = 0; j < frags; j++) {

				tx_cons = NEXT_TX(tx_cons);

				tx_buf = &txr->tx_buf_ring[tx_cons];

				page_pool_recycle_direct(rxr->page_pool, tx_buf->page);

			}

		}

		tx_cons = NEXT_TX(tx_cons);

	}
@@ -103,6 +165,7 @@ void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) 
	if (rx_doorbell_needed) {

		tx_buf = &txr->tx_buf_ring[last_tx_cons];

		bnxt_db_write(bp, &rxr->rx_db, tx_buf->rx_prod);



	}

}
@@ -133,6 +196,23 @@ void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, 
	xdp_prepare_buff(xdp, *data_ptr - offset, offset, *len, false);

}



void bnxt_xdp_buff_frags_free(struct bnxt_rx_ring_info *rxr,

			      struct xdp_buff *xdp)

{

	struct skb_shared_info *shinfo;

	int i;



	if (!xdp || !xdp_buff_has_frags(xdp))

		return;

	shinfo = xdp_get_shared_info_from_buff(xdp);

	for (i = 0; i < shinfo->nr_frags; i++) {

		struct page *page = skb_frag_page(&shinfo->frags[i]);



		page_pool_recycle_direct(rxr->page_pool, page);

	}

	shinfo->nr_frags = 0;

}



/* returns the following:

 * true    - packet consumed by XDP and new buffer is allocated.

 * false   - packet should be passed to the stack.
@@ -145,6 +225,7 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons, 
	struct bnxt_sw_rx_bd *rx_buf;

	struct pci_dev *pdev;

	dma_addr_t mapping;

	u32 tx_needed = 1;

	void *orig_data;

	u32 tx_avail;

	u32 offset;
@@ -180,18 +261,28 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons, 
	case XDP_TX:

		rx_buf = &rxr->rx_buf_ring[cons];

		mapping = rx_buf->mapping - bp->rx_dma_offset;

		*event = 0;



		if (unlikely(xdp_buff_has_frags(&xdp))) {

			struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(&xdp);



		if (tx_avail < 1) {

			tx_needed += sinfo->nr_frags;

			*event = BNXT_AGG_EVENT;

		}



		if (tx_avail < tx_needed) {

			trace_xdp_exception(bp->dev, xdp_prog, act);

			bnxt_xdp_buff_frags_free(rxr, &xdp);

			bnxt_reuse_rx_data(rxr, cons, page);

			return true;

		}



		*event = BNXT_TX_EVENT;

		dma_sync_single_for_device(&pdev->dev, mapping + offset, *len,

					   bp->rx_dir);



		*event |= BNXT_TX_EVENT;

		__bnxt_xmit_xdp(bp, txr, mapping + offset, *len,

				NEXT_RX(rxr->rx_prod));

				NEXT_RX(rxr->rx_prod), &xdp);

		bnxt_reuse_rx_data(rxr, cons, page);

		return true;

	case XDP_REDIRECT:
@@ -208,6 +299,7 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons, 
		/* if we are unable to allocate a new buffer, abort and reuse */

		if (bnxt_alloc_rx_data(bp, rxr, rxr->rx_prod, GFP_ATOMIC)) {

			trace_xdp_exception(bp->dev, xdp_prog, act);

			bnxt_xdp_buff_frags_free(rxr, &xdp);

			bnxt_reuse_rx_data(rxr, cons, page);

			return true;

		}
@@ -227,6 +319,7 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons, 
		trace_xdp_exception(bp->dev, xdp_prog, act);

		fallthrough;

	case XDP_DROP:

		bnxt_xdp_buff_frags_free(rxr, &xdp);

		bnxt_reuse_rx_data(rxr, cons, page);

		break;

	}

drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h

+4 −1
Original line number Diff line number Diff line
@@ -14,7 +14,8 @@ DECLARE_STATIC_KEY_FALSE(bnxt_xdp_locking_key); 


struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp,

				   struct bnxt_tx_ring_info *txr,

				   dma_addr_t mapping, u32 len);

				   dma_addr_t mapping, u32 len,

				   struct xdp_buff *xdp);

void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts);

bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons,

		 struct xdp_buff xdp, struct page *page, unsigned int *len,
@@ -28,6 +29,8 @@ bool bnxt_xdp_attached(struct bnxt *bp, struct bnxt_rx_ring_info *rxr); 
void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,

			u16 cons, u8 **data_ptr, unsigned int *len,

			struct xdp_buff *xdp);

void bnxt_xdp_buff_frags_free(struct bnxt_rx_ring_info *rxr,

			      struct xdp_buff *xdp);

struct sk_buff *bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb,

				   u8 num_frags, struct page_pool *pool,

				   struct xdp_buff *xdp,