From patchwork Tue Oct 18 19:15:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Lemon X-Patchwork-Id: 13010963 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0582AC4332F for ; Tue, 18 Oct 2022 19:16:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229741AbiJRTQM convert rfc822-to-8bit (ORCPT ); Tue, 18 Oct 2022 15:16:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53582 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229572AbiJRTQL (ORCPT ); Tue, 18 Oct 2022 15:16:11 -0400 Received: from mx0a-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3569B580B9 for ; Tue, 18 Oct 2022 12:16:10 -0700 (PDT) Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.17.1.5/8.17.1.5) with ESMTP id 29IDgBx3004361 for ; Tue, 18 Oct 2022 12:16:09 -0700 Received: from maileast.thefacebook.com ([163.114.130.16]) by m0001303.ppops.net (PPS) with ESMTPS id 3k9abe6w65-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Tue, 18 Oct 2022 12:16:09 -0700 Received: from twshared9384.24.frc3.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Tue, 18 Oct 2022 12:16:08 -0700 Received: by devvm2494.atn0.facebook.com (Postfix, from userid 172786) id 44055227F0509; Tue, 18 Oct 2022 12:16:02 -0700 (PDT) From: Jonathan Lemon To: CC: Subject: [RFC PATCH v2 00/13] zero-copy RX for io_uring Date: Tue, 18 Oct 2022 12:15:49 -0700 Message-ID: <20221018191602.2112515-1-jonathan.lemon@gmail.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-GUID: SWWtPse7TSz1M-rLW8WO7jCWm2PjCGNO X-Proofpoint-ORIG-GUID: SWWtPse7TSz1M-rLW8WO7jCWm2PjCGNO X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-10-18_07,2022-10-18_01,2022-06-22_01 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org This series is a RFC for io_uring/zctap. This is an evolution of the earlier zctap work, re-targeted to use io_uring as the userspace API. The current code is intended to provide a zero-copy RX path for upper-level networking protocols (aka TCP and UDP). The current draft focuses on host-provided memory (not GPU memory). This RFC contains the upper-level core code required for operation, with the intent of soliciting feedback on the general API. This does not contain the network driver side changes required for complete operation. Also please note that as an RFC, there are some things which are incomplete or in need of rework. The intent is to use a network driver which provides header/data splitting, so the frame header (which is processed by the networking stack) does not reside in user memory. The code is successfully receiving a zero-copy TCP stream from a remote sender. An RFC, the intent is to solicit feedback on the API and overall design. The current code will also work with system pages, copying the data out to the application - this is intended as a fallback/testing path. Performance numbers are coming soon! High level description: The application allocates a frame backing store, and provides this to the kernel for use. An interface queue is requested from the networking device, and incoming frames are deposited into the provided memory region. Responsibility for correctly steering incoming frames to the queue is outside the scope of this work - it is assumed that the user has set steering rules up separately. Incoming frames are sent up the stack as skb's and eventually land in the application's socket receive queue. This differs from AF_XDP, which receives raw frames directly to userspace, without protocol processing. The RECV_ZC opcode then returns an iov[] style vector which points to the data in userspace memory. When the application has completed processing of the data, the buffer is returned back to the kernel through a fill ring for reuse. Changelog: v1: initial version v2: Remove separate PROVIDE_REGION opcode, fold this functionality into REGISTER_IFQ. Remove page_pool hooks, as it appears the page pool is currently incompatible with user-mapped memory. Add io_zctap_buffers and network driver API. . Jonathan Lemon (13): io_uring: add zctap ifq definition netdevice: add SETUP_ZCTAP to the netdev_bpf structure io_uring: add register ifq opcode io_uring: create a zctap region for a mapped buffer io_uring: create page freelist for the ifq region io_uring: Provide driver API for zctap packet buffers. io_uring: Allocate the zctap buffers for the device io_uring: Add zctap buffer get/put functions and refcounting. skbuff: Introduce SKBFL_FIXED_FRAG and skb_fixed() io_uring: Allocate a uarg for use by the ifq RX io_uring: Define the zctap iov[] returned to the user. io_uring: add OP_RECV_ZC command. io_uring: Make remove_ifq_region a delayed work call include/linux/io_uring.h | 35 ++ include/linux/io_uring_types.h | 11 + include/linux/netdevice.h | 6 + include/linux/skbuff.h | 10 +- include/uapi/linux/io_uring.h | 24 + io_uring/Makefile | 3 +- io_uring/io_uring.c | 8 + io_uring/kbuf.c | 13 + io_uring/kbuf.h | 2 + io_uring/net.c | 123 +++++ io_uring/opdef.c | 15 + io_uring/zctap.c | 842 +++++++++++++++++++++++++++++++++ io_uring/zctap.h | 16 + 13 files changed, 1106 insertions(+), 2 deletions(-) create mode 100644 io_uring/zctap.c create mode 100644 io_uring/zctap.h