[PATCH 5.19 051/158] bnxt_en: Use PAGE_SIZE to init buffer when multi buffer XDP is not in use

Greg Kroah-Hartman
2022-08-29T11:22:54Z

From: Pavan Chebbi <pavan.chebbi@broadcom.com>

[ Upstream commit 7dd3de7cb1d657a918c6b2bc673c71e318aa0c05 ]

Using BNXT_PAGE_MODE_BUF_SIZE + offset as buffer length value is not
sufficient when running single buffer XDP programs doing redirect
operations. The stack will complain on missing skb tail room. Fix it
by using PAGE_SIZE when calling xdp_init_buff() for single buffer
programs.

Fixes: b231c3f3414c ("bnxt: refactor bnxt_rx_xdp to separate xdp_init_buff/xdp_prepare_buff")
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/broadcom/bnxt/bnxt.h | 1 +
drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 10 ++++++++--
2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 075c6206325ce..b1b17f9113006 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -2130,6 +2130,7 @@ 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;
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
index f53387ed0167b..c3065ec0a4798 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
@@ -181,6 +181,7 @@ void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
struct xdp_buff *xdp)
{
struct bnxt_sw_rx_bd *rx_buf;
+ u32 buflen = PAGE_SIZE;
struct pci_dev *pdev;
dma_addr_t mapping;
u32 offset;
@@ -192,7 +193,10 @@ 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);

- xdp_init_buff(xdp, BNXT_PAGE_MODE_BUF_SIZE + offset, &rxr->xdp_rxq);
+ 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);
}

@@ -397,8 +401,10 @@ 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)
--
2.35.1