@@ -58,6 +58,10 @@ definitions:
name: vlan-tag
doc:
Device is capable of exposing receive packet VLAN tag via bpf_xdp_metadata_rx_vlan_tag().
+ -
+ name: csum
+ doc:
+ Device is capable of exposing receive packet checksum via bpf_xdp_metadata_rx_csum().
-
type: flags
name: xsk-flags
@@ -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_csum
+
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
@@ -408,6 +408,10 @@ 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_CSUM, \
+ NETDEV_XDP_RX_METADATA_CSUM, \
+ bpf_xdp_metadata_rx_csum, \
+ xmo_rx_csum) \
enum xdp_rx_metadata {
#define XDP_METADATA_KFUNC(name, _, __, ___) name,
@@ -465,12 +469,46 @@ enum xdp_rss_hash_type {
XDP_RSS_TYPE_L4_IPV6_SCTP_EX = XDP_RSS_TYPE_L4_IPV6_SCTP | XDP_RSS_L3_DYNHDR,
};
+enum xdp_csum_status {
+ /* The following enums are the same as skb checksums in skbuff.h, refer to
+ * DOC: skb checksums for more details.
+ */
+
+ XDP_CHECKSUM_NONE = 0,
+ XDP_CHECKSUM_UNNECESSARY = 1,
+ /* Checksum, calculated over the entire packet is provided, as ``csum`` in
+ * ``xdp_csum_info``.
+ */
+ XDP_CHECKSUM_COMPLETE = 2,
+ /* Refer to ``csum_start`` and ``csum_offset`` in ``xdp_csum_info`` for more information. */
+ XDP_CHECKSUM_PARTIAL = 3,
+};
+
+union xdp_csum_info {
+ /* Checksum, calculated over the whole packet.
+ * Available, if ``status & XDP_CHECKSUM_COMPLETE``.
+ */
+ __wsum csum;
+ /* Checksum referred to by ``csum_start + csum_offset`` is considered
+ * valid, but was never calculated, TX device has to do this,
+ * starting from csum_start packet byte.
+ * Any preceding checksums are also considered valid.
+ * Available, if ``status == XDP_CHECKSUM_PARTIAL``.
+ */
+ struct {
+ u16 csum_start;
+ u16 csum_offset;
+ };
+};
+
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_csum)(const struct xdp_md *ctx, enum xdp_csum_status *csum_status,
+ union xdp_csum_info *csum_info);
};
#ifdef CONFIG_NET
@@ -46,11 +46,14 @@ 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_CSUM: Device is capable of exposing receive packet
+ * checksum via bpf_xdp_metadata_rx_csum().
*/
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_CSUM = 8,
};
/**
@@ -766,6 +766,29 @@ __bpf_kfunc int bpf_xdp_metadata_rx_vlan_tag(const struct xdp_md *ctx,
return -EOPNOTSUPP;
}
+/**
+ * bpf_xdp_metadata_rx_csum - Read XDP frame checksum status and info.
+ * @ctx: XDP context pointer.
+ * @csum_status: Destination pointer for checksum status.
+ * @csum_info: Destination pointer for complete checksum or partial checksum offset.
+ *
+ * Status (@csum_status) is an enum that informs what checksum processing was
+ * performed, same as sk_buff.ip_summed. Additional results of such processing,
+ * such as complete checksum or partial checksum offsets, are passed as
+ * info (@csum_info).
+ *
+ * Return:
+ * * Returns 0 on success or ``-errno`` on error.
+ * * ``-EOPNOTSUPP`` : means device driver doesn't implement kfunc
+ * * ``-ENODATA`` : means checksum status is unknown for this frame
+ */
+__bpf_kfunc int bpf_xdp_metadata_rx_csum(const struct xdp_md *ctx,
+ enum xdp_csum_status *csum_status,
+ union xdp_csum_info *csum_info)
+{
+ return -EOPNOTSUPP;
+}
+
__bpf_kfunc_end_defs();
BTF_KFUNCS_START(xdp_metadata_kfunc_ids)
@@ -46,11 +46,14 @@ 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_CSUM: Device is capable of exposing receive packet
+ * checksum via bpf_xdp_metadata_rx_csum().
*/
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_CSUM = 8,
};
/**
This is an implementation of functionality that allows drivers to expose checksum information to XDP. This information includes: - Checksum info, a union of - complete checksum, if checksum is complete - skb-style checksum start and offset, if checksum is partial - Checksum status, an enum which is the same as skb checksums in skbuff.h, identical to sk_buff.ip_summed Signed-off-by: Muyang Tian <tianmuyang@huawei.com> --- Documentation/netlink/specs/netdev.yaml | 4 +++ Documentation/networking/xdp-rx-metadata.rst | 3 ++ include/net/xdp.h | 38 ++++++++++++++++++++ include/uapi/linux/netdev.h | 3 ++ net/core/xdp.c | 23 ++++++++++++ tools/include/uapi/linux/netdev.h | 3 ++ 6 files changed, 74 insertions(+)