Add new xdp-rx-metadata-features member to netdev netlink
which exports a bitmask of supported kfuncs. Most of the patch
is autogenerated (headers), the only relevant part is netdev.yaml
and the changes in netdev-genl.c to marshal into netlink.
Example output on veth:
$ ip link add veth0 type veth peer name veth1 # ifndex == 12
$ ./tools/net/ynl/samples/netdev 12
Select ifc ($ifindex; or 0 = dump; or -2 ntf check): 12
veth1[12] xdp-features (23): basic redirect rx-sg xdp-rx-metadata-features (3): timestamp hash xdp-zc-max-segs=0
Cc: netdev@xxxxxxxxxxxxxxx
Cc: Willem de Bruijn <willemb@xxxxxxxxxx>
Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
---
Documentation/netlink/specs/netdev.yaml | 21 ++++++++++++++++++++
Documentation/networking/xdp-rx-metadata.rst | 7 +++++++
include/net/xdp.h | 5 ++++-
include/uapi/linux/netdev.h | 16 +++++++++++++++
kernel/bpf/offload.c | 2 +-
net/core/netdev-genl.c | 12 ++++++++++-
net/core/xdp.c | 4 ++--
tools/include/uapi/linux/netdev.h | 16 +++++++++++++++
8 files changed, 78 insertions(+), 5 deletions(-)
diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index 1c7284fd535b..c46fcc78fc04 100644
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -42,6 +42,19 @@ name: netdev
doc:
This feature informs if netdev implements non-linear XDP buffer
support in ndo_xdp_xmit callback.
+ -
+ type: flags
+ name: xdp-rx-metadata
+ render-max: true
+ entries:
+ -
+ name: timestamp
+ doc:
+ Device is capable of exposing receive HW timestamp via bpf_xdp_metadata_rx_timestamp().
+ -
+ name: hash
+ doc:
+ Device is capable of exposing receive packet hash via bpf_xdp_metadata_rx_hash().
attribute-sets:
-
@@ -68,6 +81,13 @@ name: netdev
type: u32
checks:
min: 1
+ -
+ name: xdp-rx-metadata-features
+ doc: Bitmask of supported XDP receive metadata features.
+ See Documentation/networking/xdp-rx-metadata.rst for more details.
+ type: u64
+ enum: xdp-rx-metadata
+ enum-as-flags: true
operations:
list:
@@ -84,6 +104,7 @@ name: netdev
- ifindex
- xdp-features
- xdp-zc-max-segs
+ - xdp-rx-metadata-features
dump:
reply: *dev-all
-
diff --git a/Documentation/networking/xdp-rx-metadata.rst b/Documentation/networking/xdp-rx-metadata.rst
index 25ce72af81c2..205696780b78 100644
--- a/Documentation/networking/xdp-rx-metadata.rst
+++ b/Documentation/networking/xdp-rx-metadata.rst
@@ -105,6 +105,13 @@ bpf_tail_call
Adding programs that access metadata kfuncs to the ``BPF_MAP_TYPE_PROG_ARRAY``
is currently not supported.
+Supported Devices
+=================
+
+It is possible to query which kfunc the particular netdev implements via
+netlink. See ``xdp-rx-metadata-features`` attribute set in
+``Documentation/netlink/specs/netdev.yaml``.
+
Example
=======
diff --git a/include/net/xdp.h b/include/net/xdp.h
index d59e12f8f311..349c36fb5fd8 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -386,19 +386,22 @@ void xdp_attachment_setup(struct xdp_attachment_info *info,
/* Define the relationship between xdp-rx-metadata kfunc and
* various other entities:
* - xdp_rx_metadata enum
+ * - netdev netlink enum (Documentation/netlink/specs/netdev.yaml)
* - kfunc name
* - xdp_metadata_ops field
*/
#define XDP_METADATA_KFUNC_xxx \
XDP_METADATA_KFUNC(XDP_METADATA_KFUNC_RX_TIMESTAMP, \
+ NETDEV_XDP_RX_METADATA_TIMESTAMP, \
bpf_xdp_metadata_rx_timestamp, \
xmo_rx_timestamp) \
XDP_METADATA_KFUNC(XDP_METADATA_KFUNC_RX_HASH, \
+ NETDEV_XDP_RX_METADATA_HASH, \
bpf_xdp_metadata_rx_hash, \
xmo_rx_hash) \
enum xdp_rx_metadata {
-#define XDP_METADATA_KFUNC(name, _, __) name,
+#define XDP_METADATA_KFUNC(name, _, __, ___) name,
XDP_METADATA_KFUNC_xxx
#undef XDP_METADATA_KFUNC
MAX_XDP_METADATA_KFUNC,
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index c1634b95c223..2943a151d4f1 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -38,11 +38,27 @@ enum netdev_xdp_act {
NETDEV_XDP_ACT_MASK = 127,
};
+/**
+ * enum netdev_xdp_rx_metadata
+ * @NETDEV_XDP_RX_METADATA_TIMESTAMP: Device is capable of exposing receive HW
+ * timestamp via bpf_xdp_metadata_rx_timestamp().
+ * @NETDEV_XDP_RX_METADATA_HASH: Device is capable of exposing receive packet
+ * hash via bpf_xdp_metadata_rx_hash().
+ */
+enum netdev_xdp_rx_metadata {
+ NETDEV_XDP_RX_METADATA_TIMESTAMP = 1,
+ NETDEV_XDP_RX_METADATA_HASH = 2,
+
+ /* private: */
+ NETDEV_XDP_RX_METADATA_MASK = 3,
+};
+
enum {
NETDEV_A_DEV_IFINDEX = 1,
NETDEV_A_DEV_PAD,
NETDEV_A_DEV_XDP_FEATURES,
NETDEV_A_DEV_XDP_ZC_MAX_SEGS,
+ NETDEV_A_DEV_XDP_RX_METADATA_FEATURES,
__NETDEV_A_DEV_MAX,
NETDEV_A_DEV_MAX = (__NETDEV_A_DEV_MAX - 1)
diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c
index 6aa6de8d715d..e7a1752b5a09 100644
--- a/kernel/bpf/offload.c
+++ b/kernel/bpf/offload.c
@@ -845,7 +845,7 @@ void *bpf_dev_bound_resolve_kfunc(struct bpf_prog *prog, u32 func_id)
if (!ops)
goto out;
-#define XDP_METADATA_KFUNC(name, _, xmo) \
+#define XDP_METADATA_KFUNC(name, _, __, xmo) \
if (func_id == bpf_xdp_metadata_kfunc_id(name)) p = ops->xmo;
XDP_METADATA_KFUNC_xxx
#undef XDP_METADATA_KFUNC
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index c1aea8b756b6..fe61f85bcf33 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -5,6 +5,7 @@
#include <linux/rtnetlink.h>
#include <net/net_namespace.h>
#include <net/sock.h>
+#include <net/xdp.h>
#include "netdev-genl-gen.h"
@@ -12,15 +13,24 @@ static int
netdev_nl_dev_fill(struct net_device *netdev, struct sk_buff *rsp,
const struct genl_info *info)
{
+ u64 xdp_rx_meta = 0;
void *hdr;
hdr = genlmsg_iput(rsp, info);
if (!hdr)
return -EMSGSIZE;
+#define XDP_METADATA_KFUNC(_, flag, __, xmo) \
+ if (netdev->xdp_metadata_ops && netdev->xdp_metadata_ops->xmo) \
+ xdp_rx_meta |= flag;
+XDP_METADATA_KFUNC_xxx
+#undef XDP_METADATA_KFUNC
+
if (nla_put_u32(rsp, NETDEV_A_DEV_IFINDEX, netdev->ifindex) ||
nla_put_u64_64bit(rsp, NETDEV_A_DEV_XDP_FEATURES,
- netdev->xdp_features, NETDEV_A_DEV_PAD)) {
+ netdev->xdp_features, NETDEV_A_DEV_PAD) ||
+ nla_put_u64_64bit(rsp, NETDEV_A_DEV_XDP_RX_METADATA_FEATURES,
+ xdp_rx_meta, NETDEV_A_DEV_PAD)) {
genlmsg_cancel(rsp, hdr);
return -EINVAL;
}
diff --git a/net/core/xdp.c b/net/core/xdp.c
index bab563b2f812..df4789ab512d 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -741,7 +741,7 @@ __bpf_kfunc int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, u32 *hash,
__diag_pop();
BTF_SET8_START(xdp_metadata_kfunc_ids)
-#define XDP_METADATA_KFUNC(_, name, __) BTF_ID_FLAGS(func, name, KF_TRUSTED_ARGS)
+#define XDP_METADATA_KFUNC(_, __, name, ___) BTF_ID_FLAGS(func, name, KF_TRUSTED_ARGS)
XDP_METADATA_KFUNC_xxx
#undef XDP_METADATA_KFUNC
BTF_SET8_END(xdp_metadata_kfunc_ids)
@@ -752,7 +752,7 @@ static const struct btf_kfunc_id_set xdp_metadata_kfunc_set = {
};
BTF_ID_LIST(xdp_metadata_kfunc_ids_unsorted)
-#define XDP_METADATA_KFUNC(name, str, _) BTF_ID(func, str)
+#define XDP_METADATA_KFUNC(name, _, str, __) BTF_ID(func, str)
XDP_METADATA_KFUNC_xxx
#undef XDP_METADATA_KFUNC
diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
index c1634b95c223..2943a151d4f1 100644
--- a/tools/include/uapi/linux/netdev.h
+++ b/tools/include/uapi/linux/netdev.h
@@ -38,11 +38,27 @@ enum netdev_xdp_act {
NETDEV_XDP_ACT_MASK = 127,
};
+/**
+ * enum netdev_xdp_rx_metadata
+ * @NETDEV_XDP_RX_METADATA_TIMESTAMP: Device is capable of exposing receive HW
+ * timestamp via bpf_xdp_metadata_rx_timestamp().
+ * @NETDEV_XDP_RX_METADATA_HASH: Device is capable of exposing receive packet
+ * hash via bpf_xdp_metadata_rx_hash().
+ */
+enum netdev_xdp_rx_metadata {
+ NETDEV_XDP_RX_METADATA_TIMESTAMP = 1,
+ NETDEV_XDP_RX_METADATA_HASH = 2,
+
+ /* private: */
+ NETDEV_XDP_RX_METADATA_MASK = 3,
+};
+
enum {
NETDEV_A_DEV_IFINDEX = 1,
NETDEV_A_DEV_PAD,
NETDEV_A_DEV_XDP_FEATURES,
NETDEV_A_DEV_XDP_ZC_MAX_SEGS,
+ NETDEV_A_DEV_XDP_RX_METADATA_FEATURES,
__NETDEV_A_DEV_MAX,
NETDEV_A_DEV_MAX = (__NETDEV_A_DEV_MAX - 1)
--
2.42.0.283.g2d96d420d3-goog
