From patchwork Tue Jan 23 22:17:45 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 191230 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:7300:2553:b0:103:945f:af90 with SMTP id p19csp640963dyi; Tue, 23 Jan 2024 14:30:44 -0800 (PST) X-Google-Smtp-Source: AGHT+IE2+8/W6UcAPU6YVNV9OZEezkjssMAYxUgr5kCb+Rk1QQS2esvPU6TuEXhzGZWtuXUDjTH+ X-Received: by 2002:a05:6a20:144b:b0:19c:5c8b:e779 with SMTP id a11-20020a056a20144b00b0019c5c8be779mr1480320pzi.84.1706049044512; Tue, 23 Jan 2024 14:30:44 -0800 (PST) ARC-Seal: i=2; a=rsa-sha256; t=1706049044; cv=pass; d=google.com; s=arc-20160816; b=ehnutVbsxqEFCoX63/LFJQOMU+fGe6hlC5Z8EQwUDRI5FjXhF5FfXIXCcM0voBW1S1 DzC6E4Ruw7dSJowZ4xClnqjr+yafMP5Ivb7PVtN/2XsB/SKsV2Zaexo/yoPyREr9ihRM SCKr1nrvREgjcTe7NnIcxBnFiFWbKrUoLSgtxijAi/B7yzayrefQtCkCfelOcz5SF7iu RKgE4h/VbArTwd1+3JQGMocgBU/uC+5ToplxwCeJP9+8Xt/WXmbk/B2xQpkNrnj4IT1J uPUk3uov75bFjOsidEt2WQdGnfoO5N0tki80R+c8XwJ38Z+OGForZZ/KcCVaMUkeJEFQ qh9w== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=cc:to:from:subject:message-id:references:mime-version :list-unsubscribe:list-subscribe:list-id:precedence:in-reply-to:date :dkim-signature; bh=sq2A5rdPoZzXe3JfsyjEi2DmgNcsMleYf8+7wJXU3oU=; fh=3zG4NHuhPxuhQ6Shw7Nt9BiRVbWd7elghbVYpfpS9LI=; b=wbkhzlpv+Jab6zk74Juv+5bKpsMblxrZpPXqQT/CCUl8h1dbE3JFHmXxKO/8YnyCN9 MeYXV2EBW+Purzq6gRLlIZhSREsKNeBvonddSJ+khUkemBryFDxBKFpMRqZEVjWXzwPb aQB5k7An21yQLCEva6QVOP5p+dE6dOHkE1m2VboLTghy3yqP4boWfUSLHB472cXb7ASc 0wb67KnpQy9w9tvg+9GZwtzX229uKW20JH2Tmk0FtjWTkPbpCTA4Z01kyqKQab3nkyy0 dg2mhB+GRvR2LAHMg/L0oSLkNCcimF3SrAoW0vmF5WE6thh+D5TUIwltkmJ7TydMSpEK Go7A== ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=bvAyWCgT; arc=pass (i=1 spf=pass spfdomain=flex--almasrymina.bounces.google.com dkim=pass dkdomain=google.com dmarc=pass fromdomain=google.com); spf=pass (google.com: domain of linux-kernel+bounces-36125-ouuuleilei=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) smtp.mailfrom="linux-kernel+bounces-36125-ouuuleilei=gmail.com@vger.kernel.org"; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from sy.mirrors.kernel.org (sy.mirrors.kernel.org. [2604:1380:40f1:3f00::1]) by mx.google.com with ESMTPS id j10-20020a170902690a00b001d453cffb92si10152888plk.620.2024.01.23.14.30.44 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Jan 2024 14:30:44 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-36125-ouuuleilei=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) client-ip=2604:1380:40f1:3f00::1; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=bvAyWCgT; arc=pass (i=1 spf=pass spfdomain=flex--almasrymina.bounces.google.com dkim=pass dkdomain=google.com dmarc=pass fromdomain=google.com); spf=pass (google.com: domain of linux-kernel+bounces-36125-ouuuleilei=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) smtp.mailfrom="linux-kernel+bounces-36125-ouuuleilei=gmail.com@vger.kernel.org"; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sy.mirrors.kernel.org (Postfix) with ESMTPS id 6423EB2A0E0 for ; Tue, 23 Jan 2024 22:18:52 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id DB1A050249; Tue, 23 Jan 2024 22:18:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="bvAyWCgT" Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 361BF4F216 for ; Tue, 23 Jan 2024 22:17:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706048278; cv=none; b=F8dlxw+Iddv4TyCScTfMEXvM1N/0b8CdSBb0gEMp22VieQ2+bV+n2tyXsJHpzFzSdZbbTE6sIatxmYTbM2fcZxzgqiETXvdz2kOe8XGK2GCDzA2YP0Pc5lxmZrUcp8kFSssBXaMrExhEN5vqiIBf8nrcq+e7EsI3975oqp+Y8cQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706048278; c=relaxed/simple; bh=eQc/0XprESJCX8/SL8NWCcerd2+39PRmvZ4jwBgHHms=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=kcrzFSp2ONcdzHNZ4h3LXGyEJC6sgOb1CGMGpejlhdlgTZaIh+80MhTwmPkZAp3zaq2HGuuPihxGBPxAhiljNbm3igtB8O7eYlDFY3ppK3mSq3KrkXM6V/sHIHIlz64nnYZ8Dtsih74WkaTv95xSz+V998R7yz53v24j9eSXZcg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=bvAyWCgT; arc=none smtp.client-ip=209.85.219.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com Received: by mail-yb1-f202.google.com with SMTP id 3f1490d57ef6-dc236791689so6612378276.3 for ; Tue, 23 Jan 2024 14:17:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1706048276; x=1706653076; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=sq2A5rdPoZzXe3JfsyjEi2DmgNcsMleYf8+7wJXU3oU=; b=bvAyWCgTdB7xqhlCHl4FccHzz0TK4HuT69XojP7Cihu+xUqrUNsjr6aNdFRlc0lsA6 oVP+JJe+KMh22It+JjF8vj3488kwKDj6QU20MRaBCLEZ1i8xL+HzBcyLfACMM/GAmzkc KTaARTv6Pgz+NXkYt8/JkL35I0bDegpG5Eug7Ry8RDHnbw34yfpkPqaeKOO7bph7hcCb Hz3IzdfhsiEoI7zRO/kpcKycv9QKpLW7Gqcl/msLocu02G6gQCaYgUYPyWAzNu5qRZUj 2Z7BEswmWXCYGl6FBdDwUgEIgTT8CGLjVoEGurlb5lE3NpvaAlXYiFfM8/E8QngSuMFR shoQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706048276; x=1706653076; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=sq2A5rdPoZzXe3JfsyjEi2DmgNcsMleYf8+7wJXU3oU=; b=TDYwVqrGrPxeit3rtiGRwvDk8aPUV1uhvs+/2nqwaQtEet3VPTh7p/B5gXs5p2NBjT pvMc05IuGm8CdcS2I8i22ZQt2iE+tjcxlxuB7EDII2ksrIBPZ00SF17su1SYv0lPbtWH KMpjXQ9v1rbjDDWj3qN0p4B9vCc6/YS16PM8ZxJ+bmUE3j29U3wJ6ml0bTBHoryUgkea pof30gG2WSSIjKP/owAhdYfcPtL4nK/226FNdcMM4RNa9lroU7ygzYy2O5pvkeHalLWL 0bjrVhVnEXNxe20Tk25oZSjxtVQsoUqc23IfBjLgSCmgjoeUcOd1uDENLYY8sEA+Rrfz DYcg== X-Gm-Message-State: AOJu0YzXcWD3mTA6jcMeRC1WMzxYlJyt0UMTM590FbsD9vpcoxKcB25U vNX0sqklAfT6fTf/GtS//sG0Ui7ZZ1pS2Y+YKNhwXKvv4FHTw+QYZW+IJG+5IYH82XnT5HiV7ae IGzYxyxmGegQpm+elv6QUIKo8oE9/TcaYmDytiTwgOMYW7C8YS46Ruu29pT3sorQi5RmXvjepTJ QQNWr+VxPUpW81FwcPwnCnigeRWKxwYvxGG5WACnCfqooaGTfrcTI9g+hTFQ8qe4BM60o= X-Received: from almasrymina.svl.corp.google.com ([2620:15c:2c4:200:3608:aa16:52d:3594]) (user=almasrymina job=sendgmr) by 2002:a05:6902:86:b0:dbe:a214:888c with SMTP id h6-20020a056902008600b00dbea214888cmr3189553ybs.11.1706048276193; Tue, 23 Jan 2024 14:17:56 -0800 (PST) Date: Tue, 23 Jan 2024 14:17:45 -0800 In-Reply-To: <20240123221749.793069-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240123221749.793069-1-almasrymina@google.com> X-Mailer: git-send-email 2.43.0.429.g432eaa2c6b-goog Message-ID: <20240123221749.793069-2-almasrymina@google.com> Subject: [PATCH net-next v6 1/2] net: introduce abstraction for network memory From: Mina Almasry To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: Mina Almasry , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jason Gunthorpe , " =?utf-8?q?Christian_K=C3=B6nig?= " , Shakeel Butt , Yunsheng Lin , Willem de Bruijn X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1788922082931937443 X-GMAIL-MSGID: 1788922082931937443 Add the netmem_ref type, an abstraction for network memory. To add support for new memory types to the net stack, we must first abstract the current memory type. Currently parts of the net stack use struct page directly: - page_pool - drivers - skb_frag_t Originally the plan was to reuse struct page* for the new memory types, and to set the LSB on the page* to indicate it's not really a page. However, for compiler type checking we need to introduce a new type. netmem_ref is introduced to abstract the underlying memory type. Currently it's a no-op abstraction that is always a struct page underneath. In parallel there is an undergoing effort to add support for devmem to the net stack: https://lore.kernel.org/netdev/20231208005250.2910004-1-almasrymina@google.com/ netmem_ref can be pointers to different underlying memory types, and the low bits are set to indicate the memory type. Helpers are provided to convert netmem pointers to the underlying memory type (currently only struct page). In the devmem series helpers are provided so that calling code can use netmem without worrying about the underlying memory type unless absolutely necessary. Reviewed-by: Shakeel Butt Signed-off-by: Mina Almasry --- v6: - Applied Reviewed-by from Shakeel. rfc v5: - RFC due to merge window. - Change to 'typedef unsigned long __bitwise netmem_ref;' - Fixed commit message (Shakeel). - Did not apply Shakeel's reviewed-by since the code changed significantly. v4: - use 'struct netmem;' instead of 'typedef void *__bitwise netmem_ref;' Using __bitwise with a non-integer type was wrong and triggered many patchwork bot errors/warnings. Using an integer type causes the compiler to warn when casting NULL to the integer type. Attempt to use an empty struct for our opaque network memory. v3: - Modify struct netmem from a union of struct page + new types to an opaque netmem_ref type. I went with: +typedef void *__bitwise netmem_ref; rather than this that Jakub recommended: +typedef unsigned long __bitwise netmem_ref; Because with the latter the compiler issues warnings to cast NULL to netmem_ref. I hope that's ok. - Add some function docs. v2: - Use container_of instead of a type cast (David). --- include/net/netmem.h | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 include/net/netmem.h diff --git a/include/net/netmem.h b/include/net/netmem.h new file mode 100644 index 000000000000..9f327d964782 --- /dev/null +++ b/include/net/netmem.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 + * + * Network memory + * + * Author: Mina Almasry + */ + +#ifndef _NET_NETMEM_H +#define _NET_NETMEM_H + +/** + * netmem_ref - a nonexistent type marking a reference to generic network + * memory. + * + * A netmem_ref currently is always a reference to a struct page. This + * abstraction is introduced so support for new memory types can be added. + * + * Use the supplied helpers to obtain the underlying memory pointer and fields. + */ +typedef unsigned long __bitwise netmem_ref; + +/* This conversion fails (returns NULL) if the netmem_ref is not struct page + * backed. + * + * Currently struct page is the only possible netmem, and this helper never + * fails. + */ +static inline struct page *netmem_to_page(netmem_ref netmem) +{ + return (__force struct page *)netmem; +} + +/* Converting from page to netmem is always safe, because a page can always be + * a netmem. + */ +static inline netmem_ref page_to_netmem(struct page *page) +{ + return (__force netmem_ref)page; +} + +#endif /* _NET_NETMEM_H */ From patchwork Tue Jan 23 22:17:46 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 191215 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:7300:2553:b0:103:945f:af90 with SMTP id p19csp636338dyi; Tue, 23 Jan 2024 14:19:07 -0800 (PST) X-Google-Smtp-Source: AGHT+IFe1cOQ+T0Yr+EyuIhWR+Y9FG4+3dYQfqAoyZ+/ZSJNhv1d1En/QO8D9gjg/zNK+itLQCqZ X-Received: by 2002:a25:f202:0:b0:dc2:544c:4d08 with SMTP id i2-20020a25f202000000b00dc2544c4d08mr4224118ybe.72.1706048347765; Tue, 23 Jan 2024 14:19:07 -0800 (PST) ARC-Seal: i=2; a=rsa-sha256; t=1706048347; cv=pass; d=google.com; s=arc-20160816; b=GhNa6opfgdhThFAC5HM3tLkmZi045VwPgP9v/IVjBY62jc7bZRkiOfctCjgwdGYGB+ qwJHoD5ea1upCear4V5Zc46qvOxh86VPRjoT/JlyMzkuQcM3vuq2bKs7LUyGsiydYUv3 6PWHSFbC2Wfmj5o+xCU7CB2eMdMSml8foA8AGyDGMdIoKf0pJ5cuwGSckxigFRd+6FZR 3Enc8g0LKX79zHOae1qvMscp4jGWW/DmN373f1CMfQMxrk1B7l4iA8MQnKE0nZV9K8OW 5g0KlK2yQzqCtcmtV/7JMDXQ0Hkd0J1R9Gn2LpxcgvmpBZZqmMv/DcZ40NbwHlx77Rmi d+zQ== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=cc:to:from:subject:message-id:references:mime-version :list-unsubscribe:list-subscribe:list-id:precedence:in-reply-to:date :dkim-signature; bh=DG8n/4xX8724j2bfPJayGJM6rCsGGHElPdEgTxPb0tY=; fh=3zG4NHuhPxuhQ6Shw7Nt9BiRVbWd7elghbVYpfpS9LI=; b=rpHqHqkOmnHZQ8nZOSsiyJ1iIJKBNf/mGoh/Fkmp2nZCnE7M175PAhSf3NWhetyfI5 zWWembcn+UEPWp08K4/P7Tc4whGTGt8GiMwmlG643cP3V8TQQLtN9r7Ss7kJhmtNuMag XfX00rKwz5RbjsiKwaSg0PjqUe7dxbHJxF0SeCo7PuhZzMdCEoklLEiXgIktxOYFPHpp gSqEaF4fbvFxk3PscOsZGIYFPizz5pBnDMpgyL++9X2FhWu0Mj7tq+tmUIx8nM/Uu/k0 hNFHyQ2JiQAlVtedVmtdYwTf8atjiwJYMXJ57rQ+WO5/NKm9WQOQPthPxuGeFqRoGIah O++Q== ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=YL8sxtqb; arc=pass (i=1 spf=pass spfdomain=flex--almasrymina.bounces.google.com dkim=pass dkdomain=google.com dmarc=pass fromdomain=google.com); spf=pass (google.com: domain of linux-kernel+bounces-36126-ouuuleilei=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) smtp.mailfrom="linux-kernel+bounces-36126-ouuuleilei=gmail.com@vger.kernel.org"; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from ny.mirrors.kernel.org (ny.mirrors.kernel.org. [147.75.199.223]) by mx.google.com with ESMTPS id u21-20020a05620a455500b0078358771b7csi9621453qkp.296.2024.01.23.14.19.07 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Jan 2024 14:19:07 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-36126-ouuuleilei=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=YL8sxtqb; arc=pass (i=1 spf=pass spfdomain=flex--almasrymina.bounces.google.com dkim=pass dkdomain=google.com dmarc=pass fromdomain=google.com); spf=pass (google.com: domain of linux-kernel+bounces-36126-ouuuleilei=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) smtp.mailfrom="linux-kernel+bounces-36126-ouuuleilei=gmail.com@vger.kernel.org"; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ny.mirrors.kernel.org (Postfix) with ESMTPS id 777AD1C2573D for ; Tue, 23 Jan 2024 22:19:07 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C4B3D4F203; Tue, 23 Jan 2024 22:18:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="YL8sxtqb" Received: from mail-yw1-f201.google.com (mail-yw1-f201.google.com [209.85.128.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 584154F614 for ; Tue, 23 Jan 2024 22:17:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706048281; cv=none; b=oQ5qNoPCV9G0Y9nIV7BHOG1R3FfvBaxJC2/9YS+FkO++YAYylWAG5GIH/FJyW3iOQ6BRUWKb5H4gQ2xtoFjKGjIo+oQ/ZCFb7xpezyZakPYwC51mmkIRE3a3ee3MejI1wxdli9Koy95Xw4iOLTivmmbw9NvRUEmc3Ra4oRM8gaE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706048281; c=relaxed/simple; bh=bPYInUrJbx3vaccTXvngVZ4XSF0X2OBJbKqHeTmr8bg=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=RIMObMdq6WRtqbYir+L3EjqmuPrjUDzcHfT+h0+vrBt73AjhDHFZ29pv+g+l0rxHw0gp2ck0QLcxmn+u1EqFmxylI8wTXiBMBlhA/IP7cScBAFHZydsBle4i9Si36lhpMh8NAKto6HingSC3Muc6NbOqCyRH/ePDo7Zi6k/Rdys= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=YL8sxtqb; arc=none smtp.client-ip=209.85.128.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com Received: by mail-yw1-f201.google.com with SMTP id 00721157ae682-5f874219ff9so66192837b3.0 for ; Tue, 23 Jan 2024 14:17:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1706048278; x=1706653078; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=DG8n/4xX8724j2bfPJayGJM6rCsGGHElPdEgTxPb0tY=; b=YL8sxtqbE8HBE0CCJ7ZJ4ecBxf4lAM2NCguq5UuSUxbaCg9RtS5UTlqs+fRoMpPaFt HsqvetwdjJVRSV9NxCiMtZjDyEgkDiRI3QfgEGnC9f9DBzipIGt6mppfosqhWkyHxNtr 9umsZhtraUX6TUehlqID21aH+1C/Q3UnS/qgFfoIKXmwMb47QkFfxSi1C5IfgIR2Rjh0 A/hEsKmGUwUjUcKDMta/8So4rtE3QfDho1cWKj+BYWntY97QmGHRjo42bKTpaX2SkcTG xAG8QZoMrJwIH9M/iv8LuSzCvvU6nMW51xLQ2LBxjbQ3ecMTKB8fckGPO7vKsAYr1LST ruRQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706048278; x=1706653078; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=DG8n/4xX8724j2bfPJayGJM6rCsGGHElPdEgTxPb0tY=; b=mylYi2spCUuC50tCcRwQ7MTQuy7meSz+d/L3ZJ5KB8MtuzRZcOsFyNa7Del7/1oWFK ufPcFU65vg+alSyn2iimVS3/bCYaWmzO9aiUqdgSHdUcX9T9HqRg4pnwaa8jWlFHGWIp GlqTiT7yDQ/7tsTqi4vDHf49xkc8FyFfkdNeiSEQkL7Uq6WhhJosGlgB2blihnYrUNCp SYWR8lfB0Wg8YrUXEM7D346AyfjkZqWYgdGcDbovlj7JdA+UAWb7pjE9oT84iMhXQPow SA+GnaWjwuMzPc0il5zbNF7jAKjadU9kbr+uZ1N1zpkwB8eSXH3AZdX8weiieqczxwIp fM1Q== X-Gm-Message-State: AOJu0Yy8yrNRWBvv9WC/tN3GVUOpaIYTU1eciY7nNTLDUmdhPJuwdL8O lxY2PMsXAFZ8cOP+3UyfnZlD6LcBTx6YWkFywdrDg90UjalslEPuzt0Y1oCUDLkM/xb33x7xqhB R2WTbhq+wqlWdp7zYR9YxWLFsoTrIljnxmIqL+GcDvX4gQmfLW7inIYG6nlT3TXDnw1kJlMfaLY m+1eLfJ+HnIJnnaS41KIArD/nKMg0Bz66eASVVGEryDgRXdPve/CqKvAwrG1aXKhEelUA= X-Received: from almasrymina.svl.corp.google.com ([2620:15c:2c4:200:3608:aa16:52d:3594]) (user=almasrymina job=sendgmr) by 2002:a0d:ca0f:0:b0:5ff:5d80:ba1 with SMTP id m15-20020a0dca0f000000b005ff5d800ba1mr121315ywd.4.1706048278230; Tue, 23 Jan 2024 14:17:58 -0800 (PST) Date: Tue, 23 Jan 2024 14:17:46 -0800 In-Reply-To: <20240123221749.793069-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240123221749.793069-1-almasrymina@google.com> X-Mailer: git-send-email 2.43.0.429.g432eaa2c6b-goog Message-ID: <20240123221749.793069-3-almasrymina@google.com> Subject: [PATCH net-next v6 2/2] net: add netmem to skb_frag_t From: Mina Almasry To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: Mina Almasry , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jason Gunthorpe , " =?utf-8?q?Christian_K=C3=B6nig?= " , Shakeel Butt , Yunsheng Lin , Willem de Bruijn X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1788921352549708172 X-GMAIL-MSGID: 1788921352549708172 Use struct netmem* instead of page in skb_frag_t. Currently struct netmem* is always a struct page underneath, but the abstraction allows efforts to add support for skb frags not backed by pages. There is unfortunately 1 instance where the skb_frag_t is assumed to be a exactly a bio_vec in kcm. For this case, WARN_ON_ONCE and return error before doing a cast. Add skb[_frag]_fill_netmem_*() and skb_add_rx_frag_netmem() helpers so that the API can be used to create netmem skbs. Signed-off-by: Mina Almasry --- v6: - Add static_asserts to validate skb_frag_t to bio_vec cast in kcm_write_msg (Yunsheng) v4: - Handle error in kcm_write_msgs() instead of only warning (Willem) v3: - Renamed the fields in skb_frag_t. v2: - Add skb frag filling helpers. --- include/linux/skbuff.h | 90 +++++++++++++++++++++++++++++------------- net/core/skbuff.c | 40 ++++++++++++++++--- net/kcm/kcmsock.c | 9 ++++- 3 files changed, 104 insertions(+), 35 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 2dde34c29203..196b9b6e6ece 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -37,6 +37,7 @@ #endif #include #include +#include /** * DOC: skb checksums @@ -359,7 +360,11 @@ extern int sysctl_max_skb_frags; */ #define GSO_BY_FRAGS 0xFFFF -typedef struct bio_vec skb_frag_t; +typedef struct skb_frag { + netmem_ref netmem; + unsigned int len; + unsigned int offset; +} skb_frag_t; /** * skb_frag_size() - Returns the size of a skb fragment @@ -367,7 +372,7 @@ typedef struct bio_vec skb_frag_t; */ static inline unsigned int skb_frag_size(const skb_frag_t *frag) { - return frag->bv_len; + return frag->len; } /** @@ -377,7 +382,7 @@ static inline unsigned int skb_frag_size(const skb_frag_t *frag) */ static inline void skb_frag_size_set(skb_frag_t *frag, unsigned int size) { - frag->bv_len = size; + frag->len = size; } /** @@ -387,7 +392,7 @@ static inline void skb_frag_size_set(skb_frag_t *frag, unsigned int size) */ static inline void skb_frag_size_add(skb_frag_t *frag, int delta) { - frag->bv_len += delta; + frag->len += delta; } /** @@ -397,7 +402,7 @@ static inline void skb_frag_size_add(skb_frag_t *frag, int delta) */ static inline void skb_frag_size_sub(skb_frag_t *frag, int delta) { - frag->bv_len -= delta; + frag->len -= delta; } /** @@ -417,7 +422,7 @@ static inline bool skb_frag_must_loop(struct page *p) * skb_frag_foreach_page - loop over pages in a fragment * * @f: skb frag to operate on - * @f_off: offset from start of f->bv_page + * @f_off: offset from start of f->netmem * @f_len: length from f_off to loop over * @p: (temp var) current page * @p_off: (temp var) offset from start of current page, @@ -2429,22 +2434,37 @@ static inline unsigned int skb_pagelen(const struct sk_buff *skb) return skb_headlen(skb) + __skb_pagelen(skb); } +static inline void skb_frag_fill_netmem_desc(skb_frag_t *frag, + netmem_ref netmem, int off, + int size) +{ + frag->netmem = netmem; + frag->offset = off; + skb_frag_size_set(frag, size); +} + static inline void skb_frag_fill_page_desc(skb_frag_t *frag, struct page *page, int off, int size) { - frag->bv_page = page; - frag->bv_offset = off; - skb_frag_size_set(frag, size); + skb_frag_fill_netmem_desc(frag, page_to_netmem(page), off, size); +} + +static inline void __skb_fill_netmem_desc_noacc(struct skb_shared_info *shinfo, + int i, netmem_ref netmem, + int off, int size) +{ + skb_frag_t *frag = &shinfo->frags[i]; + + skb_frag_fill_netmem_desc(frag, netmem, off, size); } static inline void __skb_fill_page_desc_noacc(struct skb_shared_info *shinfo, int i, struct page *page, int off, int size) { - skb_frag_t *frag = &shinfo->frags[i]; - - skb_frag_fill_page_desc(frag, page, off, size); + __skb_fill_netmem_desc_noacc(shinfo, i, page_to_netmem(page), off, + size); } /** @@ -2460,10 +2480,10 @@ static inline void skb_len_add(struct sk_buff *skb, int delta) } /** - * __skb_fill_page_desc - initialise a paged fragment in an skb + * __skb_fill_netmem_desc - initialise a fragment in an skb * @skb: buffer containing fragment to be initialised - * @i: paged fragment index to initialise - * @page: the page to use for this fragment + * @i: fragment index to initialise + * @netmem: the netmem to use for this fragment * @off: the offset to the data with @page * @size: the length of the data * @@ -2472,10 +2492,12 @@ static inline void skb_len_add(struct sk_buff *skb, int delta) * * Does not take any additional reference on the fragment. */ -static inline void __skb_fill_page_desc(struct sk_buff *skb, int i, - struct page *page, int off, int size) +static inline void __skb_fill_netmem_desc(struct sk_buff *skb, int i, + netmem_ref netmem, int off, int size) { - __skb_fill_page_desc_noacc(skb_shinfo(skb), i, page, off, size); + struct page *page = netmem_to_page(netmem); + + __skb_fill_netmem_desc_noacc(skb_shinfo(skb), i, netmem, off, size); /* Propagate page pfmemalloc to the skb if we can. The problem is * that not all callers have unique ownership of the page but rely @@ -2483,7 +2505,20 @@ static inline void __skb_fill_page_desc(struct sk_buff *skb, int i, */ page = compound_head(page); if (page_is_pfmemalloc(page)) - skb->pfmemalloc = true; + skb->pfmemalloc = true; +} + +static inline void __skb_fill_page_desc(struct sk_buff *skb, int i, + struct page *page, int off, int size) +{ + __skb_fill_netmem_desc(skb, i, page_to_netmem(page), off, size); +} + +static inline void skb_fill_netmem_desc(struct sk_buff *skb, int i, + netmem_ref netmem, int off, int size) +{ + __skb_fill_netmem_desc(skb, i, netmem, off, size); + skb_shinfo(skb)->nr_frags = i + 1; } /** @@ -2503,8 +2538,7 @@ static inline void __skb_fill_page_desc(struct sk_buff *skb, int i, static inline void skb_fill_page_desc(struct sk_buff *skb, int i, struct page *page, int off, int size) { - __skb_fill_page_desc(skb, i, page, off, size); - skb_shinfo(skb)->nr_frags = i + 1; + skb_fill_netmem_desc(skb, i, page_to_netmem(page), off, size); } /** @@ -2530,6 +2564,8 @@ static inline void skb_fill_page_desc_noacc(struct sk_buff *skb, int i, void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, int size, unsigned int truesize); +void skb_add_rx_frag_netmem(struct sk_buff *skb, int i, netmem_ref netmem, + int off, int size, unsigned int truesize); void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size, unsigned int truesize); @@ -3378,7 +3414,7 @@ static inline void skb_propagate_pfmemalloc(const struct page *page, */ static inline unsigned int skb_frag_off(const skb_frag_t *frag) { - return frag->bv_offset; + return frag->offset; } /** @@ -3388,7 +3424,7 @@ static inline unsigned int skb_frag_off(const skb_frag_t *frag) */ static inline void skb_frag_off_add(skb_frag_t *frag, int delta) { - frag->bv_offset += delta; + frag->offset += delta; } /** @@ -3398,7 +3434,7 @@ static inline void skb_frag_off_add(skb_frag_t *frag, int delta) */ static inline void skb_frag_off_set(skb_frag_t *frag, unsigned int offset) { - frag->bv_offset = offset; + frag->offset = offset; } /** @@ -3409,7 +3445,7 @@ static inline void skb_frag_off_set(skb_frag_t *frag, unsigned int offset) static inline void skb_frag_off_copy(skb_frag_t *fragto, const skb_frag_t *fragfrom) { - fragto->bv_offset = fragfrom->bv_offset; + fragto->offset = fragfrom->offset; } /** @@ -3420,7 +3456,7 @@ static inline void skb_frag_off_copy(skb_frag_t *fragto, */ static inline struct page *skb_frag_page(const skb_frag_t *frag) { - return frag->bv_page; + return netmem_to_page(frag->netmem); } /** @@ -3524,7 +3560,7 @@ static inline void *skb_frag_address_safe(const skb_frag_t *frag) static inline void skb_frag_page_copy(skb_frag_t *fragto, const skb_frag_t *fragfrom) { - fragto->bv_page = fragfrom->bv_page; + fragto->netmem = fragfrom->netmem; } bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio); diff --git a/net/core/skbuff.c b/net/core/skbuff.c index edbbef563d4d..b930de02e2ed 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -115,6 +115,24 @@ static struct kmem_cache *skb_small_head_cache __ro_after_init; int sysctl_max_skb_frags __read_mostly = MAX_SKB_FRAGS; EXPORT_SYMBOL(sysctl_max_skb_frags); +/* kcm_write_msgs() relies on casting paged frags to bio_vec to use + * iov_iter_bvec(). These static asserts ensure the cast is valid is long as the + * netmem is a page. + */ +static_assert(offsetof(struct bio_vec, bv_page) == + offsetof(skb_frag_t, netmem)); +static_assert(sizeof_field(struct bio_vec, bv_page) == + sizeof_field(skb_frag_t, netmem)); + +static_assert(offsetof(struct bio_vec, bv_len) == offsetof(skb_frag_t, len)); +static_assert(sizeof_field(struct bio_vec, bv_len) == + sizeof_field(skb_frag_t, len)); + +static_assert(offsetof(struct bio_vec, bv_offset) == + offsetof(skb_frag_t, offset)); +static_assert(sizeof_field(struct bio_vec, bv_offset) == + sizeof_field(skb_frag_t, offset)); + #undef FN #define FN(reason) [SKB_DROP_REASON_##reason] = #reason, static const char * const drop_reasons[] = { @@ -845,16 +863,24 @@ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len, } EXPORT_SYMBOL(__napi_alloc_skb); -void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, - int size, unsigned int truesize) +void skb_add_rx_frag_netmem(struct sk_buff *skb, int i, netmem_ref netmem, + int off, int size, unsigned int truesize) { DEBUG_NET_WARN_ON_ONCE(size > truesize); - skb_fill_page_desc(skb, i, page, off, size); + skb_fill_netmem_desc(skb, i, netmem, off, size); skb->len += size; skb->data_len += size; skb->truesize += truesize; } +EXPORT_SYMBOL(skb_add_rx_frag_netmem); + +void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, + int size, unsigned int truesize) +{ + skb_add_rx_frag_netmem(skb, i, page_to_netmem(page), off, size, + truesize); +} EXPORT_SYMBOL(skb_add_rx_frag); void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size, @@ -1906,10 +1932,11 @@ int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask) /* skb frags point to kernel buffers */ for (i = 0; i < new_frags - 1; i++) { - __skb_fill_page_desc(skb, i, head, 0, psize); + __skb_fill_netmem_desc(skb, i, page_to_netmem(head), 0, psize); head = (struct page *)page_private(head); } - __skb_fill_page_desc(skb, new_frags - 1, head, 0, d_off); + __skb_fill_netmem_desc(skb, new_frags - 1, page_to_netmem(head), 0, + d_off); skb_shinfo(skb)->nr_frags = new_frags; release: @@ -3647,7 +3674,8 @@ skb_zerocopy(struct sk_buff *to, struct sk_buff *from, int len, int hlen) if (plen) { page = virt_to_head_page(from->head); offset = from->data - (unsigned char *)page_address(page); - __skb_fill_page_desc(to, 0, page, offset, plen); + __skb_fill_netmem_desc(to, 0, page_to_netmem(page), + offset, plen); get_page(page); j = 1; len -= plen; diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index 1184d40167b8..145ef22b2b35 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -636,9 +636,14 @@ static int kcm_write_msgs(struct kcm_sock *kcm) for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) msize += skb_frag_size(&skb_shinfo(skb)->frags[i]); + if (WARN_ON_ONCE(!skb_frag_page(&skb_shinfo(skb)->frags[0]))) { + ret = -EINVAL; + goto out; + } + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, - skb_shinfo(skb)->frags, skb_shinfo(skb)->nr_frags, - msize); + (const struct bio_vec *)skb_shinfo(skb)->frags, + skb_shinfo(skb)->nr_frags, msize); iov_iter_advance(&msg.msg_iter, txm->frag_offset); do {