From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from outbound.qs.icloud.com (qs-2004k-snip4-4.eps.apple.com [57.103.84.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F1FDC3DEAD8 for ; Wed, 8 Jul 2026 20:34:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=57.103.84.107 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783542898; cv=none; b=AgXd2gL6Efj2TuZsGiVzALAPwYfLt8uVuEmp+jZa76kC7/mA4r7D5LglFYi7/qv/uYJrjkoV5eWcqTLmHtwthmmxQ8csRq+o/YjdWoZkMFoTxxYHEQ4h4iBZd4ZqVxn4DS9vQpDBGd2t4w7nUCuwV7w6yesh/XJz7z+GKRYTO3A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783542898; c=relaxed/simple; bh=W0ywNbROrfj8PczOQlXHQMtMXu6sowi9LgL+SfU9bJ0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EkuhgYwxgObidctYaSQFoSpnxPvKzDebo9UB9fd2tAFLZHbrEU1AdcXM+kufSOxQVVS5RrOKEZflcUbNN8ZFMw+LaAjXwSJ64yKgptrEE3IuxEbzushlDKNVHaLMLSPUIISe8VW7G4dikv50nTT2oZqms7G7FftDDBcRPpd7wd0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=verdict.gg; spf=pass smtp.mailfrom=verdict.gg; dkim=pass (2048-bit key) header.d=verdict.gg header.i=@verdict.gg header.b=jo9P2YG5; arc=none smtp.client-ip=57.103.84.107 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=verdict.gg Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=verdict.gg Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=verdict.gg header.i=@verdict.gg header.b="jo9P2YG5" Received: from outbound.qs.icloud.com (unknown [127.0.0.2]) by p00-icloudmta-asmtp-us-east-2d-10-percent-0 (Postfix) with ESMTPS id 5C30330001DB; Wed, 08 Jul 2026 20:34:49 +0000 (UTC) X-ICL-RepId: 019f4370-bb51-7097-92a4-d2b694e5ff07 X-ICL-Out-Info: HUtFAUMHWwJACUgBTUQeDx5WFlZNRAJCTQhICkMGWQJeCEABQwVdEhVdRVcIWwJAEVc4RQhFD1sTTVZUChcNVk1PHUEJXghGXl4fEx9UVgFDGRBWAVhWXQVNGlwYWQ8cAUpWWg5bBEcUFxtcABcbRgIEIwJfAEUCXglWATAXD1ZNTx1BCV4IRl5eHxMAXg8PTAtIAVsHXAJIC0gAWQZbHEQMSQFcGlkfFFwUWh9WBXIGXApXBFQfHBdeRhMZThtXTVoNQBlYBm0UVhVSBFk= Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=verdict.gg; s=sig1; t=1783542893; x=1786134893; bh=9qnLAUdw3PZEBWM4qb317DK5nF1B/uRKVs7vMdge6Y0=; h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme; b=jo9P2YG5BqA67LQhcVhFNAZIDmPuJoYjLPxW5HSJUujZ8V2JRDfIkx02A0Lq7XdfNZ2CHGjmnp7Uy5ETv1KfUUPw6wJc0RxDTM5MEIa4CPVp2IMzdq34Ou6Wyc/2AC/46EwrhoGKoKqpvHT1MTHBWhV+3tmMHY4NlphGpxAQRZeuN1YcYXvdDlBqUq+frlgP6gS2zwlgr5vSNUzdW18iZmdKlkQDCD6JuGWcN8pAUjLyCWUmOCqMtOAXqUR5ByWf9QTyjQcZdmCSbkrXJJmMLbmRiLMX9RErJg4+7HMgu4y2WRyydYIDSi502vtcOq4oHzWHy2pZi1KRFoJd33cqig== mail-alias-created-date: 1621344842221 Received: from DelNac.mail.msk (unknown [17.57.155.37]) by p00-icloudmta-asmtp-us-east-2d-10-percent-0 (Postfix) with ESMTPSA id B62CA30001E8; Wed, 08 Jul 2026 20:34:43 +0000 (UTC) From: Vladimir Vdovin To: Lorenzo Bianconi , Donald Hunter , Jakub Kicinski , "David S . Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Stanislav Fomichev , Andrew Lunn , Tony Nguyen , Przemek Kitszel , Alexander Lobakin , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , KP Singh , Hao Luo , Jiri Olsa , Shuah Khan , Maciej Fijalkowski Cc: Jakub Sitnicki , Aleksandr Loktionov , netdev@vger.kernel.org, bpf@vger.kernel.org, intel-wired-lan@lists.osuosl.org, linux-kselftest@vger.kernel.org, Vladimir Vdovin Subject: [PATCH bpf-next v4 1/6] netlink: specs: Add XDP RX checksum capability to XDP metadata specs Date: Wed, 8 Jul 2026 23:34:05 +0300 Message-ID: <20260708203410.45121-2-deliran@verdict.gg> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20260708203410.45121-1-deliran@verdict.gg> References: <20260708203410.45121-1-deliran@verdict.gg> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-ORIG-GUID: 4Mqo4vDqr1O9VHLhC0ahqjJ2yP2dzZUz X-Proofpoint-GUID: 4Mqo4vDqr1O9VHLhC0ahqjJ2yP2dzZUz X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNzA4MDIwMiBTYWx0ZWRfXyut/mrNNuBW6 eaBwByxVOIq2v6+NsMeEbGyb3Ts72tRe4HM0muDe8hQs+46QDx5jx2YDKSHAnsJA7ueNJ2/xu+t yRxuEgmsem8HZ7DUYK+QvrmocQRU8D2kTZHCAp56D7q1cXPoH6S0FbV1a55oezI77RD5cAVskI8 Lxv2OpBWz5PvnklhVnivdy+LqH1OMSxXIpKVzg1qabM5eMBMU8OOYVwSxqTM5uNCjV3A0jj13IO iL/xA11N7WCBi5/ZThFHBO0gZoYmNKNeoeTvqltq1PcGFR0ABS3e6yZjwfvpv34hEkSOn6RJbZH g8s7u71IfwG/wUkDqZD From: Lorenzo Bianconi 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. Signed-off-by: Lorenzo Bianconi Signed-off-by: Vladimir Vdovin --- Documentation/netlink/specs/netdev.yaml | 5 ++++ include/net/xdp.h | 18 ++++++++++++++ include/uapi/linux/netdev.h | 3 +++ net/core/xdp.c | 32 +++++++++++++++++++++++++ tools/include/uapi/linux/netdev.h | 3 +++ 5 files changed, 61 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/include/net/xdp.h b/include/net/xdp.h index aa742f413c35..e255ff786131 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 +647,26 @@ enum xdp_rss_hash_type { XDP_RSS_TYPE_L4_IPV6_SCTP_EX = XDP_RSS_TYPE_L4_IPV6_SCTP | XDP_RSS_L3_DYNHDR, }; +/* Please note the driver is required to invalidate the checksum if the NIC + * reports CHECKSUM_UNNECESSARY or CHECKSUM_COMPLETE and the eBPF program + * modifies the packet since it can change some fields validated by the + * checksum. + */ +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, }; /** -- 2.47.0