From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.tipi-net.de (mail.tipi-net.de [194.13.80.246]) (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 16AE437881C; Thu, 19 Mar 2026 11:54:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=194.13.80.246 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773921303; cv=none; b=nTMJJrqbfS8iM8I0OD86Y04S0l4EC46rIB4QfCxR98vQb2pFaT2NH7UkNbD8HO7KMDLnHj+tb0AytwEvmvzHPB606WRg1sBOu17p7htWqpGr4rj/c880sfW/ufcURJaI3Y3T3oN7fwXiRsX15okmSISL//8544yHcWL1fV91reA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773921303; c=relaxed/simple; bh=ypYwrUihhPq9cDKeiQ0JTeLy6A6BpK7ULFzZ4bjaV7I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PzY5Xywqq8taBLtro4CCXRQEWaZLQdfKLPUB62iJfPgHcY/+qMVItZdaHCRdv4CuB0doJqgXczmTdSN9PihTe5JqRU4zlb76Q2gyys5JBla9cmNKE8jJjzAgBpQha78Ykej+rCWACIIAZNKau0zQlbaFlrvf+1EDNaBZ1AtF/E0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tipi-net.de; spf=pass smtp.mailfrom=tipi-net.de; dkim=pass (2048-bit key) header.d=tipi-net.de header.i=@tipi-net.de header.b=npUcn9qr; arc=none smtp.client-ip=194.13.80.246 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tipi-net.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=tipi-net.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=tipi-net.de header.i=@tipi-net.de header.b="npUcn9qr" Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 19167A57F7; Thu, 19 Mar 2026 12:54:52 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tipi-net.de; s=dkim; t=1773921292; h=from:subject:date:message-id:to:cc:mime-version: content-transfer-encoding:in-reply-to:references; bh=avacMX5F1rsv7hRO/fsrWSUbWYUtEqZhEx6vbLpXWgM=; b=npUcn9qrjPFTzwdJMTRtAmXbH3CWotHwb8nWIPc7VpaVfOJfrmGK6z7kUxb4NefzlgWuaQ 4oy8pputB3i9JXBNE+U5KXfHj4RjCQvgQsotEKZbk/3loWKe++3hkHt4me81x74LFenJ/v EyFVeNb/PbYzhVpv/0Q/EqEOBpg//MpTal1lH1f0UuI1EeX6Mm7hPQA6Jo7XKt9JfDnFtJ ofk+jS6tND02x1fqQgxLJuw4XxGK3Ubwq2Rgz6gLA+SrGhw2eQCVssl13QLs4LnAZspJqN /aw+Uqh8hZLaUdohBMdOADEs14VpmN+ZeyFXYN13MtRf8rj5LmXKqBJE5DMgXw== From: Nicolai Buchwitz To: netdev@vger.kernel.org Cc: Nicolai Buchwitz , Doug Berger , Florian Fainelli , Broadcom internal kernel review list , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Stanislav Fomichev , linux-kernel@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH net-next v3 5/6] net: bcmgenet: add XDP_REDIRECT and ndo_xdp_xmit support Date: Thu, 19 Mar 2026 12:53:58 +0100 Message-ID: <20260319115402.353509-6-nb@tipi-net.de> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260319115402.353509-1-nb@tipi-net.de> References: <20260319115402.353509-1-nb@tipi-net.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Last-TLS-Session-Version: TLSv1.3 Add XDP_REDIRECT support and implement ndo_xdp_xmit for receiving redirected frames from other devices. XDP_REDIRECT calls xdp_do_redirect() in the RX path with xdp_do_flush() once per NAPI poll cycle. ndo_xdp_xmit batches frames into ring 16 under a single spinlock acquisition. Advertise NETDEV_XDP_ACT_REDIRECT and NETDEV_XDP_ACT_NDO_XMIT in xdp_features. Signed-off-by: Nicolai Buchwitz --- .../net/ethernet/broadcom/genet/bcmgenet.c | 98 +++++++++++++++---- 1 file changed, 80 insertions(+), 18 deletions(-) diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c index 54df1694f1cd..a5ad25ccb148 100644 --- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c +++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c @@ -2320,23 +2320,23 @@ static struct sk_buff *bcmgenet_xdp_build_skb(struct bcmgenet_rx_ring *ring, return skb; } +/* Submit a single XDP frame to the TX ring. Caller must hold ring->lock. + * Returns true on success. Does not ring the doorbell - caller must + * write TDMA_PROD_INDEX after batching. + */ static bool bcmgenet_xdp_xmit_frame(struct bcmgenet_priv *priv, + struct bcmgenet_tx_ring *ring, struct xdp_frame *xdpf, bool dma_map) { - struct bcmgenet_tx_ring *ring = &priv->tx_rings[DESC_INDEX]; struct device *kdev = &priv->pdev->dev; struct enet_cb *tx_cb_ptr; dma_addr_t mapping; unsigned int dma_len; u32 len_stat; - spin_lock(&ring->lock); - - if (ring->free_bds < 1) { - spin_unlock(&ring->lock); + if (ring->free_bds < 1) return false; - } tx_cb_ptr = bcmgenet_get_txcb(priv, ring); @@ -2350,7 +2350,6 @@ bcmgenet_xdp_xmit_frame(struct bcmgenet_priv *priv, */ if (unlikely(xdpf->headroom < sizeof(struct status_64))) { bcmgenet_put_txcb(priv, ring); - spin_unlock(&ring->lock); return false; } @@ -2364,7 +2363,6 @@ bcmgenet_xdp_xmit_frame(struct bcmgenet_priv *priv, tx_cb_ptr->skb = NULL; tx_cb_ptr->xdpf = NULL; bcmgenet_put_txcb(priv, ring); - spin_unlock(&ring->lock); return false; } } else { @@ -2396,12 +2394,15 @@ bcmgenet_xdp_xmit_frame(struct bcmgenet_priv *priv, ring->prod_index++; ring->prod_index &= DMA_P_INDEX_MASK; + return true; +} + +static void +bcmgenet_xdp_ring_doorbell(struct bcmgenet_priv *priv, + struct bcmgenet_tx_ring *ring) +{ bcmgenet_tdma_ring_writel(priv, ring->index, ring->prod_index, TDMA_PROD_INDEX); - - spin_unlock(&ring->lock); - - return true; } static unsigned int @@ -2417,7 +2418,11 @@ bcmgenet_run_xdp(struct bcmgenet_rx_ring *ring, struct bpf_prog *prog, switch (act) { case XDP_PASS: return XDP_PASS; - case XDP_TX: + case XDP_TX: { + struct bcmgenet_tx_ring *tx_ring; + + tx_ring = &priv->tx_rings[DESC_INDEX]; + /* Prepend a zeroed TSB (Transmit Status Block). The GENET * MAC has TBUF_64B_EN set globally, so hardware expects every * TX buffer to begin with a 64-byte struct status_64. Back @@ -2429,14 +2434,26 @@ bcmgenet_run_xdp(struct bcmgenet_rx_ring *ring, struct bpf_prog *prog, memset(xdp->data, 0, sizeof(struct status_64)); xdpf = xdp_convert_buff_to_frame(xdp); - if (unlikely(!xdpf) || - unlikely(!bcmgenet_xdp_xmit_frame(priv, xdpf, false))) { - page_pool_put_full_page(ring->page_pool, rx_page, - true); + if (unlikely(!xdpf)) + goto drop_page; + + spin_lock(&tx_ring->lock); + if (unlikely(!bcmgenet_xdp_xmit_frame(priv, tx_ring, + xdpf, false))) { + spin_unlock(&tx_ring->lock); + xdp_return_frame_rx_napi(xdpf); return XDP_DROP; } + bcmgenet_xdp_ring_doorbell(priv, tx_ring); + spin_unlock(&tx_ring->lock); return XDP_TX; + } + case XDP_REDIRECT: + if (unlikely(xdp_do_redirect(priv->dev, xdp, prog))) + goto drop_page; + return XDP_REDIRECT; case XDP_DROP: +drop_page: page_pool_put_full_page(ring->page_pool, rx_page, true); return XDP_DROP; default: @@ -2459,6 +2476,7 @@ static unsigned int bcmgenet_desc_rx(struct bcmgenet_rx_ring *ring, struct bcmgenet_priv *priv = ring->priv; struct net_device *dev = priv->dev; struct bpf_prog *xdp_prog; + bool xdp_flush = false; struct enet_cb *cb; struct sk_buff *skb; u32 dma_length_status; @@ -2597,6 +2615,8 @@ static unsigned int bcmgenet_desc_rx(struct bcmgenet_rx_ring *ring, xdp_act = bcmgenet_run_xdp(ring, xdp_prog, &xdp, rx_page); + if (xdp_act == XDP_REDIRECT) + xdp_flush = true; if (xdp_act != XDP_PASS) goto next; @@ -2670,6 +2690,9 @@ static unsigned int bcmgenet_desc_rx(struct bcmgenet_rx_ring *ring, bcmgenet_rdma_ring_writel(priv, ring->index, ring->c_index, RDMA_CONS_INDEX); } + if (xdp_flush) + xdp_do_flush(); + ring->dim.bytes = bytes_processed; ring->dim.packets = rxpktprocessed; @@ -3995,10 +4018,16 @@ static int bcmgenet_xdp_setup(struct net_device *dev, return -EOPNOTSUPP; } + if (!prog) + xdp_features_clear_redirect_target(dev); + old_prog = xchg(&priv->xdp_prog, prog); if (old_prog) bpf_prog_put(old_prog); + if (prog) + xdp_features_set_redirect_target(dev, false); + return 0; } @@ -4012,6 +4041,37 @@ static int bcmgenet_xdp(struct net_device *dev, struct netdev_bpf *xdp) } } +static int +bcmgenet_xdp_xmit(struct net_device *dev, int num_frames, + struct xdp_frame **frames, u32 flags) +{ + struct bcmgenet_priv *priv = netdev_priv(dev); + struct bcmgenet_tx_ring *ring = &priv->tx_rings[DESC_INDEX]; + int sent = 0; + int i; + + if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) + return -EINVAL; + + if (unlikely(!netif_running(dev))) + return -ENETDOWN; + + spin_lock(&ring->lock); + + for (i = 0; i < num_frames; i++) { + if (!bcmgenet_xdp_xmit_frame(priv, ring, frames[i], true)) + break; + sent++; + } + + if (sent) + bcmgenet_xdp_ring_doorbell(priv, ring); + + spin_unlock(&ring->lock); + + return sent; +} + static const struct net_device_ops bcmgenet_netdev_ops = { .ndo_open = bcmgenet_open, .ndo_stop = bcmgenet_close, @@ -4024,6 +4084,7 @@ static const struct net_device_ops bcmgenet_netdev_ops = { .ndo_get_stats64 = bcmgenet_get_stats64, .ndo_change_carrier = bcmgenet_change_carrier, .ndo_bpf = bcmgenet_xdp, + .ndo_xdp_xmit = bcmgenet_xdp_xmit, }; /* GENET hardware parameters/characteristics */ @@ -4326,7 +4387,8 @@ static int bcmgenet_probe(struct platform_device *pdev) NETIF_F_RXCSUM; dev->hw_features |= dev->features; dev->vlan_features |= dev->features; - dev->xdp_features = NETDEV_XDP_ACT_BASIC; + dev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT | + NETDEV_XDP_ACT_NDO_XMIT; netdev_sw_irq_coalesce_default_on(dev); -- 2.51.0