From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C96EDC54FCB for ; Wed, 22 Apr 2020 16:07:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A309421569 for ; Wed, 22 Apr 2020 16:07:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="CAUUzF+2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726381AbgDVQHm (ORCPT ); Wed, 22 Apr 2020 12:07:42 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:45498 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726154AbgDVQHl (ORCPT ); Wed, 22 Apr 2020 12:07:41 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1587571659; 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: in-reply-to:in-reply-to:references:references; bh=qVN5D4k6CPXm/CsTfZRedU5FchFYXq2H0A5tWQjBfY8=; b=CAUUzF+2NiBUwm+GxEOgTnzInJLud6v0msD1649xk0u23eT+PYsZuex7KKqTFaPhi3bsZA Khtk+XpMHb5wUDziPOFgcMhOJd7eR1JjLtQ392wCTxNqLS0FK0PSKLecfmVq4kJCkjyW49 gajOnE/zMlE7gf/oStuR55bZK61smew= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-206-YV49HgVKNa-_S5jl1L2EyQ-1; Wed, 22 Apr 2020 12:07:35 -0400 X-MC-Unique: YV49HgVKNa-_S5jl1L2EyQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7F09D107ACC7; Wed, 22 Apr 2020 16:07:33 +0000 (UTC) Received: from firesoul.localdomain (unknown [10.40.208.3]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0EBBF5C541; Wed, 22 Apr 2020 16:07:27 +0000 (UTC) Received: from [192.168.42.3] (localhost [IPv6:::1]) by firesoul.localdomain (Postfix) with ESMTP id 2FE9930000E43; Wed, 22 Apr 2020 18:07:26 +0200 (CEST) Subject: [PATCH net-next 01/33] xdp: add frame size to xdp_buff From: Jesper Dangaard Brouer To: sameehj@amazon.com Cc: Jesper Dangaard Brouer , netdev@vger.kernel.org, bpf@vger.kernel.org, zorik@amazon.com, akiyano@amazon.com, gtzalik@amazon.com, =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rgensen?= , Daniel Borkmann , Alexei Starovoitov , John Fastabend , Alexander Duyck , Jeff Kirsher , David Ahern , Willem de Bruijn , Ilias Apalodimas , Lorenzo Bianconi , Saeed Mahameed , steffen.klassert@secunet.com Date: Wed, 22 Apr 2020 18:07:26 +0200 Message-ID: <158757164613.1370371.2655437650342381672.stgit@firesoul> In-Reply-To: <158757160439.1370371.13213378122947426220.stgit@firesoul> References: <158757160439.1370371.13213378122947426220.stgit@firesoul> User-Agent: StGit/0.19 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org XDP have evolved to support several frame sizes, but xdp_buff was not updated with this information. The frame size (frame_sz) member of xdp_buff is introduced to know the real size of the memory the frame is delivered in. When introducing this also make it clear that some tailroom is reserved/required when creating SKBs using build_skb(). It would also have been an option to introduce a pointer to data_hard_end (with reserved offset). The advantage with frame_sz is that (like rxq) drivers only need to setup/assign this value once per NAPI cycle. Due to XDP-generic (and some drivers) it's not possible to store frame_sz inside xdp_rxq_info, because it's varies per packet as it can be based/depend on packet length. Signed-off-by: Jesper Dangaard Brouer --- include/net/xdp.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/include/net/xdp.h b/include/net/xdp.h index 40c6d3398458..1ccf7df98bee 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -6,6 +6,8 @@ #ifndef __LINUX_NET_XDP_H__ #define __LINUX_NET_XDP_H__ +#include /* skb_shared_info */ + /** * DOC: XDP RX-queue information * @@ -70,8 +72,19 @@ struct xdp_buff { void *data_hard_start; unsigned long handle; struct xdp_rxq_info *rxq; + u32 frame_sz; /* frame size to deduct data_hard_end/reserved tailroom*/ }; +/* Reserve memory area at end-of data area. + * + * This macro reserves tailroom in the XDP buffer by limiting the + * XDP/BPF data access to data_hard_end. Notice same area (and size) + * is used for XDP_PASS, when constructing the SKB via build_skb(). + */ +#define xdp_data_hard_end(xdp) \ + ((xdp)->data_hard_start + (xdp)->frame_sz - \ + SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) + struct xdp_frame { void *data; u16 len;