From patchwork Thu May 28 00:14:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Ahern X-Patchwork-Id: 1299282 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=default header.b=TDdxAg1V; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49XSqr5SKWz9sSF for ; Thu, 28 May 2020 10:14:32 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725956AbgE1AOb (ORCPT ); Wed, 27 May 2020 20:14:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:51536 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725896AbgE1AO2 (ORCPT ); Wed, 27 May 2020 20:14:28 -0400 Received: from C02YQ0RWLVCF.internal.digitalocean.com (c-73-181-34-237.hsd1.co.comcast.net [73.181.34.237]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B5A1720FC3; Thu, 28 May 2020 00:14:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590624868; bh=Vm4bXwI8489XcHed+ZYiV55Bkq4hi5rqYUIPriIiVc4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TDdxAg1VxSEsKsXnS1kDBAi/dPtq6KrLBeGHe0+Ow6s+kh4BOdiPr70kOkvaXFJ9/ 64tzK1+OqBU7I1uWmq4Iah/30gBDUK4JpudqMPTszfTyAPZ57bsBVBUC6su2AD/by0 PWFHSgjSHMz+MNUf2vHhHSD+KqnFe5gp12Cb7IaU= From: David Ahern To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, brouer@redhat.com, toke@redhat.com, daniel@iogearbox.net, john.fastabend@gmail.com, ast@kernel.org, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, andriin@fb.com, dsahern@gmail.com Subject: [PATCH v2 bpf-next 3/5] xdp: Add xdp_txq_info to xdp_buff Date: Wed, 27 May 2020 18:14:21 -0600 Message-Id: <20200528001423.58575-4-dsahern@kernel.org> X-Mailer: git-send-email 2.21.1 (Apple Git-122.3) In-Reply-To: <20200528001423.58575-1-dsahern@kernel.org> References: <20200528001423.58575-1-dsahern@kernel.org> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: David Ahern Add xdp_txq_info as the Tx counterpart to xdp_rxq_info. At the moment only the device is added. Other fields (queue_index) can be added as use cases arise. From a UAPI perspective, add egress_ifindex to xdp context for bpf programs to see the Tx device. Update the verifier to only allow accesses to egress_ifindex by XDP programs with BPF_XDP_DEVMAP expected attach type. Signed-off-by: David Ahern --- include/net/xdp.h | 5 +++++ include/uapi/linux/bpf.h | 2 ++ kernel/bpf/devmap.c | 3 +++ net/core/filter.c | 17 +++++++++++++++++ tools/include/uapi/linux/bpf.h | 2 ++ 5 files changed, 29 insertions(+) diff --git a/include/net/xdp.h b/include/net/xdp.h index 90f11760bd12..d54022959491 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -61,12 +61,17 @@ struct xdp_rxq_info { struct xdp_mem_info mem; } ____cacheline_aligned; /* perf critical, avoid false-sharing */ +struct xdp_txq_info { + struct net_device *dev; +}; + struct xdp_buff { void *data; void *data_end; void *data_meta; void *data_hard_start; struct xdp_rxq_info *rxq; + struct xdp_txq_info *txq; u32 frame_sz; /* frame size to deduce data_hard_end/reserved tailroom*/ }; diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 2d9927b7a922..a0ebbbe066b2 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3624,6 +3624,8 @@ struct xdp_md { /* Below access go through struct xdp_rxq_info */ __u32 ingress_ifindex; /* rxq->dev->ifindex */ __u32 rx_queue_index; /* rxq->queue_index */ + + __u32 egress_ifindex; /* txq->dev->ifindex */ }; /* DEVMAP values */ diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index a628585a31e1..73e4a6cd6c2b 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -462,8 +462,11 @@ static struct xdp_buff *dev_map_run_prog(struct net_device *dev, struct xdp_buff *xdp, struct bpf_prog *xdp_prog) { + struct xdp_txq_info txq = { .dev = dev }; u32 act; + xdp->txq = &txq; + act = bpf_prog_run_xdp(xdp_prog, xdp); switch (act) { case XDP_DROP: diff --git a/net/core/filter.c b/net/core/filter.c index a6fc23447f12..2e9dbfd8e60c 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -7014,6 +7014,13 @@ static bool xdp_is_valid_access(int off, int size, const struct bpf_prog *prog, struct bpf_insn_access_aux *info) { + if (prog->expected_attach_type != BPF_XDP_DEVMAP) { + switch (off) { + case offsetof(struct xdp_md, egress_ifindex): + return false; + } + } + if (type == BPF_WRITE) { if (bpf_prog_is_dev_bound(prog->aux)) { switch (off) { @@ -7967,6 +7974,16 @@ static u32 xdp_convert_ctx_access(enum bpf_access_type type, offsetof(struct xdp_rxq_info, queue_index)); break; + case offsetof(struct xdp_md, egress_ifindex): + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, txq), + si->dst_reg, si->src_reg, + offsetof(struct xdp_buff, txq)); + *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_txq_info, dev), + si->dst_reg, si->dst_reg, + offsetof(struct xdp_txq_info, dev)); + *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, + offsetof(struct net_device, ifindex)); + break; } return insn - insn_buf; diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 2d9927b7a922..a0ebbbe066b2 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -3624,6 +3624,8 @@ struct xdp_md { /* Below access go through struct xdp_rxq_info */ __u32 ingress_ifindex; /* rxq->dev->ifindex */ __u32 rx_queue_index; /* rxq->queue_index */ + + __u32 egress_ifindex; /* txq->dev->ifindex */ }; /* DEVMAP values */