Introduce XDP RX checksum capability to XDP metadata specs. XDP RX checksum will be use by devices capable of exposing receive checksum result via bpf_xdp_metadata_rx_checksum(). Moreover, introduce xmo_rx_checksum netdev callback in order to allow the eBPF program bound to the device to retrieve the RX checksum result computed by the hw NIC and reported via DMA descriptors.
Reviewed-by: Aleksandr Loktionov <[email protected]> Signed-off-by: Lorenzo Bianconi <[email protected]> --- Documentation/netlink/specs/netdev.yaml | 5 +++++ Documentation/networking/xdp-rx-metadata.rst | 3 +++ include/net/xdp.h | 13 +++++++++++ include/uapi/linux/netdev.h | 3 +++ net/core/xdp.c | 32 ++++++++++++++++++++++++++++ tools/include/uapi/linux/netdev.h | 3 +++ 6 files changed, 59 insertions(+) diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml index 5f143da7458c..6d0d90d3a614 100644 --- a/Documentation/netlink/specs/netdev.yaml +++ b/Documentation/netlink/specs/netdev.yaml @@ -61,6 +61,11 @@ definitions: doc: | Device is capable of exposing receive packet VLAN tag via bpf_xdp_metadata_rx_vlan_tag(). + - + name: checksum + doc: | + Device is capable of exposing receive checksum result via + bpf_xdp_metadata_rx_checksum(). - type: flags name: xsk-flags diff --git a/Documentation/networking/xdp-rx-metadata.rst b/Documentation/networking/xdp-rx-metadata.rst index efdf5eeb49e7..93918b3769a3 100644 --- a/Documentation/networking/xdp-rx-metadata.rst +++ b/Documentation/networking/xdp-rx-metadata.rst @@ -28,6 +28,9 @@ metadata is supported, this set will grow: .. kernel-doc:: net/core/xdp.c :identifiers: bpf_xdp_metadata_rx_vlan_tag +.. kernel-doc:: net/core/xdp.c + :identifiers: bpf_xdp_metadata_rx_checksum + An XDP program can use these kfuncs to read the metadata into stack variables for its own consumption. Or, to pass the metadata on to other consumers, an XDP program can store it into the metadata area carried diff --git a/include/net/xdp.h b/include/net/xdp.h index aa742f413c35..d95e126f2426 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -586,6 +586,10 @@ void xdp_attachment_setup(struct xdp_attachment_info *info, NETDEV_XDP_RX_METADATA_VLAN_TAG, \ bpf_xdp_metadata_rx_vlan_tag, \ xmo_rx_vlan_tag) \ + XDP_METADATA_KFUNC(XDP_METADATA_KFUNC_RX_CHECKSUM, \ + NETDEV_XDP_RX_METADATA_CHECKSUM, \ + bpf_xdp_metadata_rx_checksum, \ + xmo_rx_checksum) enum xdp_rx_metadata { #define XDP_METADATA_KFUNC(name, _, __, ___) name, @@ -643,12 +647,21 @@ enum xdp_rss_hash_type { XDP_RSS_TYPE_L4_IPV6_SCTP_EX = XDP_RSS_TYPE_L4_IPV6_SCTP | XDP_RSS_L3_DYNHDR, }; +enum xdp_checksum { + XDP_CHECKSUM_NONE = BIT(CHECKSUM_NONE), + XDP_CHECKSUM_UNNECESSARY = BIT(CHECKSUM_UNNECESSARY), + XDP_CHECKSUM_COMPLETE = BIT(CHECKSUM_COMPLETE), +}; + struct xdp_metadata_ops { int (*xmo_rx_timestamp)(const struct xdp_md *ctx, u64 *timestamp); int (*xmo_rx_hash)(const struct xdp_md *ctx, u32 *hash, enum xdp_rss_hash_type *rss_type); int (*xmo_rx_vlan_tag)(const struct xdp_md *ctx, __be16 *vlan_proto, u16 *vlan_tci); + int (*xmo_rx_checksum)(const struct xdp_md *ctx, + enum xdp_checksum *ip_summed, + u32 *cksum, u8 *cksum_level); }; #ifdef CONFIG_NET diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h index 2f3ab75e8cc0..f8caade93c8c 100644 --- a/include/uapi/linux/netdev.h +++ b/include/uapi/linux/netdev.h @@ -47,11 +47,14 @@ enum netdev_xdp_act { * hash via bpf_xdp_metadata_rx_hash(). * @NETDEV_XDP_RX_METADATA_VLAN_TAG: Device is capable of exposing receive * packet VLAN tag via bpf_xdp_metadata_rx_vlan_tag(). + * @NETDEV_XDP_RX_METADATA_CHECKSUM: Device is capable of exposing receive + * checksum result via bpf_xdp_metadata_rx_checksum(). */ enum netdev_xdp_rx_metadata { NETDEV_XDP_RX_METADATA_TIMESTAMP = 1, NETDEV_XDP_RX_METADATA_HASH = 2, NETDEV_XDP_RX_METADATA_VLAN_TAG = 4, + NETDEV_XDP_RX_METADATA_CHECKSUM = 8, }; /** diff --git a/net/core/xdp.c b/net/core/xdp.c index 9890a30584ba..9bcaa423ad17 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -961,6 +961,38 @@ __bpf_kfunc int bpf_xdp_metadata_rx_vlan_tag(const struct xdp_md *ctx, return -EOPNOTSUPP; } +/** + * bpf_xdp_metadata_rx_checksum - Read XDP frame RX checksum. + * @ctx: XDP context pointer. + * @ip_summed: Return value pointer to a bitmask indicating available checksums. + * @cksum: Return value pointer indicating the hw checksum value. + * @cksum_level: Return value pointer indicating the checksum level result. + * + * In case of success, ``ip_summed`` is set to the RX checksum result. Possible + * values are: + * ``XDP_CHECKSUM_NONE`` + * ``XDP_CHECKSUM_UNNECESSARY`` + * ``XDP_CHECKSUM_COMPLETE`` + * ``XDP_CHECKSUM_COMPLETE`` | ``XDP_CHECKSUM_UNNECESSARY`` + * + * In case of success, ``cksum`` contains the checksum value calculated by the + * NIC. ``cksum`` is valid only if ``XDP_CHECKSUM_COMPLETE`` is set in + * ``ip_summed``. ``cksum_level`` contains the checksum level reported by the + * hw. ``cksum_level`` can be considered valid only if + * ``XDP_CHECKSUM_UNNECESSARY`` is set in ``ip_summed``. + * + * Return: + * * Returns 0 on success or ``-errno`` on error. + * * ``-EOPNOTSUPP`` : means device driver does not implement kfunc + * * ``-ENODATA`` : means no RX-checksum available for this frame + */ +__bpf_kfunc int bpf_xdp_metadata_rx_checksum(const struct xdp_md *ctx, + enum xdp_checksum *ip_summed, + u32 *cksum, u8 *cksum_level) +{ + return -EOPNOTSUPP; +} + __bpf_kfunc_end_defs(); BTF_KFUNCS_START(xdp_metadata_kfunc_ids) diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h index 2f3ab75e8cc0..f8caade93c8c 100644 --- a/tools/include/uapi/linux/netdev.h +++ b/tools/include/uapi/linux/netdev.h @@ -47,11 +47,14 @@ enum netdev_xdp_act { * hash via bpf_xdp_metadata_rx_hash(). * @NETDEV_XDP_RX_METADATA_VLAN_TAG: Device is capable of exposing receive * packet VLAN tag via bpf_xdp_metadata_rx_vlan_tag(). + * @NETDEV_XDP_RX_METADATA_CHECKSUM: Device is capable of exposing receive + * checksum result via bpf_xdp_metadata_rx_checksum(). */ enum netdev_xdp_rx_metadata { NETDEV_XDP_RX_METADATA_TIMESTAMP = 1, NETDEV_XDP_RX_METADATA_HASH = 2, NETDEV_XDP_RX_METADATA_VLAN_TAG = 4, + NETDEV_XDP_RX_METADATA_CHECKSUM = 8, }; /** -- 2.55.0
