Re: [PATCH RFC bpf-next 4/6] net: ice: Add xmo_rx_checksum callback

On Sat, Sep 20, 2025 at 02:20:30PM +0200, Lorenzo Bianconi wrote:

Implement xmo_rx_checksum callback in ice driver to report RX checksum result to the eBPF program bounded to the NIC.

Tested-by: Jesper Dangaard Brouer hawk@kernel.org Signed-off-by: Lorenzo Bianconi lorenzo@kernel.org

---

drivers/net/ethernet/intel/ice/ice_base.c | 1 + drivers/net/ethernet/intel/ice/ice_txrx.h | 1 + drivers/net/ethernet/intel/ice/ice_txrx_lib.c | 82 +++++++++++++++++++++++++++ 3 files changed, 84 insertions(+)

diff --git a/drivers/net/ethernet/intel/ice/ice_base.c b/drivers/net/ethernet/intel/ice/ice_base.c index c5da8e9cc0a0e5551b340e70628813999059bcfe..e8ec419bdc98cb1f01e3c088698b0c4c0f97748f 100644 --- a/drivers/net/ethernet/intel/ice/ice_base.c +++ b/drivers/net/ethernet/intel/ice/ice_base.c @@ -591,6 +591,7 @@ static int ice_vsi_cfg_rxq(struct ice_rx_ring *ring) } }

• ring->pkt_ctx.rxq_flags = ring->flags; xdp_init_buff(&ring->xdp, ice_get_frame_sz(ring), &ring->xdp_rxq); ring->xdp.data = NULL; ring->xdp_ext.pkt_ctx = &ring->pkt_ctx;

diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.h b/drivers/net/ethernet/intel/ice/ice_txrx.h index 2fd8e78178a271c15fc054ef553bd509b1c8f8f3..96a2bb79e5e95fa0b9c6287eb9769bdecf47dec1 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx.h +++ b/drivers/net/ethernet/intel/ice/ice_txrx.h @@ -260,6 +260,7 @@ enum ice_rx_dtype { struct ice_pkt_ctx { u64 cached_phctime; __be16 vlan_proto;

• u8 rxq_flags;

}; struct ice_xdp_buff { diff --git a/drivers/net/ethernet/intel/ice/ice_txrx_lib.c b/drivers/net/ethernet/intel/ice/ice_txrx_lib.c index 45cfaabc41cbeb9b119a0e95547e012e0df1e188..5327b0389ec1a3708a469fa9986a1e565b20ecf7 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx_lib.c +++ b/drivers/net/ethernet/intel/ice/ice_txrx_lib.c @@ -555,6 +555,87 @@ static int ice_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash, return 0; } +/**

• • ice_xdp_rx_checksum - RX checksum XDP hint handler
• • @ctx: XDP buff pointer
• • @ip_summed: RX checksum result destination address
• • @cksum_meta: XDP RX checksum metadata destination address
• • Copy RX checksum result (if available) and its metadata to the
• • destination address.
• */

+static int ice_xdp_rx_checksum(const struct xdp_md *ctx, u8 *ip_summed,

• 	       u32 *cksum_meta)
  

Hi Lorenzo,

any chance we could have some common code used both here and in ice_rx_csum() ?

+{

• const struct ice_xdp_buff *xdp_ext = (void *)ctx;
• const union ice_32b_rx_flex_desc *rx_desc = xdp_ext->eop_desc;
• u16 rx_status0, rx_status1, ptype = ice_get_ptype(rx_desc);
• struct libeth_rx_pt decoded = libie_rx_pt_parse(ptype);
• bool ipv4, ipv6;
• if (!libeth_rx_pt_has_checksum(xdp_ext->xdp_buff.rxq->dev, decoded))

• goto checksum_none;
  

• rx_status0 = le16_to_cpu(rx_desc->wb.status_error0);
• rx_status1 = le16_to_cpu(rx_desc->wb.status_error1);
• if ((xdp_ext->pkt_ctx->rxq_flags & ICE_RX_FLAGS_RING_GCS) &&

•    rx_desc->wb.rxdid == ICE_RXDID_FLEX_NIC &&
  

•    (decoded.inner_prot == LIBETH_RX_PT_INNER_TCP ||
  

•     decoded.inner_prot == LIBETH_RX_PT_INNER_UDP ||
  

•     decoded.inner_prot == LIBETH_RX_PT_INNER_ICMP)) {
  

• const struct ice_32b_rx_flex_desc_nic *desc;
  

• u16 csum;
  

• desc = (struct ice_32b_rx_flex_desc_nic *)rx_desc;
  

• *ip_summed = CHECKSUM_COMPLETE;
  

• csum = (__force u16)desc->raw_csum;
  

• *cksum_meta = csum_unfold((__force __sum16)swab16(csum));
  

• return 0;
  

• }
• /* check if HW has decoded the packet and checksum */
• if (!(rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_L3L4P_S)))

• goto checksum_none;
  

• ipv4 = libeth_rx_pt_get_ip_ver(decoded) == LIBETH_RX_PT_OUTER_IPV4;
• if (ipv4 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EIPE_S))))

• goto checksum_none;
  

• if (ipv4 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_IPE_S))))

• goto checksum_none;
  

• ipv6 = libeth_rx_pt_get_ip_ver(decoded) == LIBETH_RX_PT_OUTER_IPV6;
• if (ipv6 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_IPV6EXADD_S))))

• goto checksum_none;
  

• /* check for L4 errors and handle packets that were not able to be

• * checksummed due to arrival speed
  

• */
  

• if (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_L4E_S))

• goto checksum_none;
  

• /* check for outer UDP checksum error in tunneled packets */
• if ((rx_status1 & BIT(ICE_RX_FLEX_DESC_STATUS1_NAT_S)) &&

•    (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EUDPE_S)))
  

• goto checksum_none;
  

• /* If there is an outer header present that might contain a checksum

• * we need to bump the checksum level by 1 to reflect the fact that
  

• * we are indicating we validated the inner checksum.
  

• */
  

• if (decoded.tunnel_type >= LIBETH_RX_PT_TUNNEL_IP_GRENAT)

• *cksum_meta = 1;
  

• *ip_summed = CHECKSUM_UNNECESSARY;
• return 0;

+checksum_none:

• *ip_summed = CHECKSUM_NONE;
• *cksum_meta = 0;
• return 0;

+}

/**

• ice_xdp_rx_vlan_tag - VLAN tag XDP hint handler
• @ctx: XDP buff pointer

@@ -584,4 +665,5 @@ const struct xdp_metadata_ops ice_xdp_md_ops = { .xmo_rx_timestamp = ice_xdp_rx_hw_ts, .xmo_rx_hash = ice_xdp_rx_hash, .xmo_rx_vlan_tag = ice_xdp_rx_vlan_tag,

• .xmo_rx_checksum = ice_xdp_rx_checksum,

};

-- 2.51.0