From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mail.toke.dk (Postfix) with ESMTPS id 7AB269F6E13 for ; Tue, 21 Mar 2023 14:52:38 +0100 (CET) Authentication-Results: mail.toke.dk; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=O/L3EMoV DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1679406757; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=NKGCgFqY7ArwF0AL3MK2xFVBlJMuZ/y6sH3A7OQOvkM=; b=O/L3EMoVAVsWx4QCTPcm5YWFC/JepK1ZjYmQKznSJn1knw+ayd9Mn3XJzQjB+L1O3mHRuA bOk2YChV8j9eaNSF3A7LaTpda/xCgnCf2wWdYLowPztQ3KU8ARVxbksS5ax1DFE9C3ug2E xndUsII7p77jRGklA4XZn3kvFaOJ+Kc= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-178-N1pSd_bSOQaw3mdF8Y3H-g-1; Tue, 21 Mar 2023 09:52:33 -0400 X-MC-Unique: N1pSd_bSOQaw3mdF8Y3H-g-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id AAAAA101A531; Tue, 21 Mar 2023 13:52:32 +0000 (UTC) Received: from firesoul.localdomain (unknown [10.45.242.23]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4B7C185768; Tue, 21 Mar 2023 13:52:32 +0000 (UTC) Received: from [10.1.1.1] (localhost [IPv6:::1]) by firesoul.localdomain (Postfix) with ESMTP id 4C5D330721A6C; Tue, 21 Mar 2023 14:52:31 +0100 (CET) From: Jesper Dangaard Brouer To: bpf@vger.kernel.org Date: Tue, 21 Mar 2023 14:52:31 +0100 Message-ID: <167940675120.2718408.8176058626864184420.stgit@firesoul> User-Agent: StGit/1.4 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Message-ID-Hash: VY2GZSDGNE5QLIJ4W6UOGVVBITYPPS4Q X-Message-ID-Hash: VY2GZSDGNE5QLIJ4W6UOGVVBITYPPS4Q X-MailFrom: brouer@redhat.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: Jesper Dangaard Brouer , netdev@vger.kernel.org, Stanislav Fomichev , martin.lau@kernel.org, ast@kernel.org, daniel@iogearbox.net, alexandr.lobakin@intel.com, larysa.zaremba@intel.com, xdp-hints@xdp-project.net, anthony.l.nguyen@intel.com, yoong.siang.song@intel.com, boon.leong.ong@intel.com, intel-wired-lan@lists.osuosl.org, pabeni@redhat.com, jesse.brandeburg@intel.com, kuba@kernel.org, edumazet@google.com, john.fastabend@gmail.com, hawk@kernel.org, davem@davemloft.net X-Mailman-Version: 3.3.8 Precedence: list Subject: [xdp-hints] [PATCH bpf V2] xdp: bpf_xdp_metadata use EOPNOTSUPP for no driver support List-Id: XDP hardware hints design discussion Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: When driver doesn't implement a bpf_xdp_metadata kfunc the fallback implementation returns EOPNOTSUPP, which indicate device driver doesn't implement this kfunc. Currently many drivers also return EOPNOTSUPP when the hint isn't available, which is ambiguous from an API point of view. Instead change drivers to return ENODATA in these cases. There can be natural cases why a driver doesn't provide any hardware info for a specific hint, even on a frame to frame basis (e.g. PTP). Lets keep these cases as separate return codes. When describing the return values, adjust the function kernel-doc layout to get proper rendering for the return values. Fixes: ab46182d0dcb ("net/mlx4_en: Support RX XDP metadata") Fixes: bc8d405b1ba9 ("net/mlx5e: Support RX XDP metadata") Fixes: 306531f0249f ("veth: Support RX XDP metadata") Fixes: 3d76a4d3d4e5 ("bpf: XDP metadata RX kfuncs") Signed-off-by: Jesper Dangaard Brouer --- Documentation/networking/xdp-rx-metadata.rst | 7 +++++-- drivers/net/ethernet/mellanox/mlx4/en_rx.c | 4 ++-- drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 4 ++-- drivers/net/veth.c | 4 ++-- net/core/xdp.c | 10 ++++++++-- 5 files changed, 19 insertions(+), 10 deletions(-) diff --git a/Documentation/networking/xdp-rx-metadata.rst b/Documentation/networking/xdp-rx-metadata.rst index aac63fc2d08b..25ce72af81c2 100644 --- a/Documentation/networking/xdp-rx-metadata.rst +++ b/Documentation/networking/xdp-rx-metadata.rst @@ -23,10 +23,13 @@ metadata is supported, this set will grow: 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 -ahead of the packet. +ahead of the packet. Not all packets will necessary have the requested +metadata available in which case the driver returns ``-ENODATA``. Not all kfuncs have to be implemented by the device driver; when not -implemented, the default ones that return ``-EOPNOTSUPP`` will be used. +implemented, the default ones that return ``-EOPNOTSUPP`` will be used +to indicate the device driver have not implemented this kfunc. + Within an XDP frame, the metadata layout (accessed via ``xdp_buff``) is as follows:: diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c index 0869d4fff17b..4b5e459b6d49 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c @@ -674,7 +674,7 @@ int mlx4_en_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp) struct mlx4_en_xdp_buff *_ctx = (void *)ctx; if (unlikely(_ctx->ring->hwtstamp_rx_filter != HWTSTAMP_FILTER_ALL)) - return -EOPNOTSUPP; + return -ENODATA; *timestamp = mlx4_en_get_hwtstamp(_ctx->mdev, mlx4_en_get_cqe_ts(_ctx->cqe)); @@ -686,7 +686,7 @@ int mlx4_en_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash) struct mlx4_en_xdp_buff *_ctx = (void *)ctx; if (unlikely(!(_ctx->dev->features & NETIF_F_RXHASH))) - return -EOPNOTSUPP; + return -ENODATA; *hash = be32_to_cpu(_ctx->cqe->immed_rss_invalid); return 0; diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c index bcd6370de440..c5dae48b7932 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c @@ -162,7 +162,7 @@ static int mlx5e_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp) const struct mlx5e_xdp_buff *_ctx = (void *)ctx; if (unlikely(!mlx5e_rx_hw_stamp(_ctx->rq->tstamp))) - return -EOPNOTSUPP; + return -ENODATA; *timestamp = mlx5e_cqe_ts_to_ns(_ctx->rq->ptp_cyc2time, _ctx->rq->clock, get_cqe_ts(_ctx->cqe)); @@ -174,7 +174,7 @@ static int mlx5e_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash) const struct mlx5e_xdp_buff *_ctx = (void *)ctx; if (unlikely(!(_ctx->xdp.rxq->dev->features & NETIF_F_RXHASH))) - return -EOPNOTSUPP; + return -ENODATA; *hash = be32_to_cpu(_ctx->cqe->rss_hash_result); return 0; diff --git a/drivers/net/veth.c b/drivers/net/veth.c index 1bb54de7124d..046461ee42ea 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -1610,7 +1610,7 @@ static int veth_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp) struct veth_xdp_buff *_ctx = (void *)ctx; if (!_ctx->skb) - return -EOPNOTSUPP; + return -ENODATA; *timestamp = skb_hwtstamps(_ctx->skb)->hwtstamp; return 0; @@ -1621,7 +1621,7 @@ static int veth_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash) struct veth_xdp_buff *_ctx = (void *)ctx; if (!_ctx->skb) - return -EOPNOTSUPP; + return -ENODATA; *hash = skb_get_hash(_ctx->skb); return 0; diff --git a/net/core/xdp.c b/net/core/xdp.c index 8d3ad315f18d..7133017bcd74 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -705,7 +705,10 @@ __diag_ignore_all("-Wmissing-prototypes", * @ctx: XDP context pointer. * @timestamp: Return value pointer. * - * Returns 0 on success or ``-errno`` on error. + * Return: + * * Returns 0 on success or ``-errno`` on error. + * * ``-EOPNOTSUPP`` : means device driver does not implement kfunc + * * ``-ENODATA`` : means no RX-timestamp available for this frame */ __bpf_kfunc int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp) { @@ -717,7 +720,10 @@ __bpf_kfunc int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx, u64 *tim * @ctx: XDP context pointer. * @hash: Return value pointer. * - * Returns 0 on success or ``-errno`` on error. + * Return: + * * Returns 0 on success or ``-errno`` on error. + * * ``-EOPNOTSUPP`` : means device driver doesn't implement kfunc + * * ``-ENODATA`` : means no RX-hash available for this frame */ __bpf_kfunc int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, u32 *hash) {