Commit 1abeacc1 authored by Michael Chan's avatar Michael Chan Committed by David S. Miller
Browse files

bnxt_en: Fix first buffer size calculations for XDP multi-buffer 



The size of the first buffer is always page size, and the useable
space is the page size minus the offset and the skb_shared_info size.
Make sure SKB and XDP buf sizes match so that the skb_shared_info
is at the same offset seen from the SKB and XDP_BUF.

build_skb() should be passed PAGE_SIZE.  xdp_init_buff() should
be passed PAGE_SIZE as well.  xdp_get_shared_info_from_buff() will
automatically deduct the skb_shared_info size if the XDP buffer
has frags.  There is no need to keep bp->xdp_has_frags.

Change BNXT_PAGE_MODE_BUF_SIZE to BNXT_MAX_PAGE_MODE_MTU_SBUF
since this constant is really the MTU with ethernet header size
subtracted.

Also fix the BNXT_MAX_PAGE_MODE_MTU macro with proper parentheses.

Fixes: 32861236 ("bnxt: change receive ring space parameters")
Reviewed-by: default avatarSomnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: default avatarAndy Gospodarek <andrew.gospodarek@broadcom.com>
Signed-off-by: default avatarMichael Chan <michael.chan@broadcom.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9b3e6078

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

+5 −4
Original line number Diff line number Diff line
@@ -991,8 +991,7 @@ static struct sk_buff *bnxt_rx_multi_page_skb(struct bnxt *bp, 
	dma_addr -= bp->rx_dma_offset;

	dma_unmap_page_attrs(&bp->pdev->dev, dma_addr, PAGE_SIZE, bp->rx_dir,

			     DMA_ATTR_WEAK_ORDERING);

	skb = build_skb(page_address(page), BNXT_PAGE_MODE_BUF_SIZE +

					    bp->rx_dma_offset);

	skb = build_skb(page_address(page), PAGE_SIZE);

	if (!skb) {

		__free_page(page);

		return NULL;
@@ -3969,8 +3968,10 @@ void bnxt_set_ring_params(struct bnxt *bp) 
		bp->rx_agg_ring_mask = (bp->rx_agg_nr_pages * RX_DESC_CNT) - 1;



		if (BNXT_RX_PAGE_MODE(bp)) {

			rx_space = BNXT_PAGE_MODE_BUF_SIZE;

			rx_size = BNXT_MAX_PAGE_MODE_MTU;

			rx_space = PAGE_SIZE;

			rx_size = PAGE_SIZE -

				  ALIGN(max(NET_SKB_PAD, XDP_PACKET_HEADROOM), 8) -

				  SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

		} else {

			rx_size = SKB_DATA_ALIGN(BNXT_RX_COPY_THRESH + NET_IP_ALIGN);

			rx_space = rx_size + NET_SKB_PAD +

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

+11 −4
Original line number Diff line number Diff line
@@ -591,12 +591,20 @@ struct nqe_cn { 
#define BNXT_RX_PAGE_SIZE (1 << BNXT_RX_PAGE_SHIFT)



#define BNXT_MAX_MTU		9500

#define BNXT_PAGE_MODE_BUF_SIZE \



/* First RX buffer page in XDP multi-buf mode

 *

 * +-------------------------------------------------------------------------+

 * | XDP_PACKET_HEADROOM | bp->rx_buf_use_size              | skb_shared_info|

 * | (bp->rx_dma_offset) |                                  |                |

 * +-------------------------------------------------------------------------+

 */

#define BNXT_MAX_PAGE_MODE_MTU_SBUF \

	((unsigned int)PAGE_SIZE - VLAN_ETH_HLEN - NET_IP_ALIGN -	\

	 XDP_PACKET_HEADROOM)

#define BNXT_MAX_PAGE_MODE_MTU	\

	BNXT_PAGE_MODE_BUF_SIZE - \

	SKB_DATA_ALIGN((unsigned int)sizeof(struct skb_shared_info))

	(BNXT_MAX_PAGE_MODE_MTU_SBUF - \

	 SKB_DATA_ALIGN((unsigned int)sizeof(struct skb_shared_info)))



#define BNXT_MIN_PKT_SIZE	52
@@ -2134,7 +2142,6 @@ struct bnxt { 
#define BNXT_DUMP_CRASH		1



	struct bpf_prog		*xdp_prog;

	u8			xdp_has_frags;



	struct bnxt_ptp_cfg	*ptp_cfg;

	u8			ptp_all_rx_tstamp;

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

+1 −6
Original line number Diff line number Diff line
@@ -193,9 +193,6 @@ void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, 
	mapping = rx_buf->mapping - bp->rx_dma_offset;

	dma_sync_single_for_cpu(&pdev->dev, mapping + offset, len, bp->rx_dir);



	if (bp->xdp_has_frags)

		buflen = BNXT_PAGE_MODE_BUF_SIZE + offset;



	xdp_init_buff(xdp, buflen, &rxr->xdp_rxq);

	xdp_prepare_buff(xdp, data_ptr - offset, offset, len, false);

}
@@ -404,10 +401,8 @@ static int bnxt_xdp_set(struct bnxt *bp, struct bpf_prog *prog) 
		netdev_warn(dev, "ethtool rx/tx channels must be combined to support XDP.\n");

		return -EOPNOTSUPP;

	}

	if (prog) {

	if (prog)

		tx_xdp = bp->rx_nr_rings;

		bp->xdp_has_frags = prog->aux->xdp_has_frags;

	}



	tc = netdev_get_num_tc(dev);

	if (!tc)