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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 16194C433EF for ; Mon, 13 Jun 2022 17:44:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236392AbiFMRoJ (ORCPT ); Mon, 13 Jun 2022 13:44:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52166 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242514AbiFMRmU (ORCPT ); Mon, 13 Jun 2022 13:42:20 -0400 Received: from mx0a-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20149674F7 for ; Mon, 13 Jun 2022 06:13:31 -0700 (PDT) Received: from pps.filterd (m0089730.ppops.net [127.0.0.1]) by m0089730.ppops.net (8.17.1.5/8.17.1.5) with ESMTP id 25D1c2hi004996 for ; Mon, 13 Jun 2022 06:13:05 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=1NhJdfddzkg0aEJBzsN0i2MMU4fyQbPWOLEMQ7xo/Cc=; b=Z4e9S0rExPJwCIMn563ZrWA4tS0k8zCPsLQejipy9s3+q33Com9g1ydPTAVrFsHznX6z gt7VCCNSMrsFutp+0sYkMjlqEDt44hvWbm4YPijNYVplTgjtxY3FnJyTJcyP8yag/dd6 tYuahcBYfwKnJ7C9Gw0Qsw/XsHIk2FIJTiw= Received: from mail.thefacebook.com ([163.114.132.120]) by m0089730.ppops.net (PPS) with ESMTPS id 3gmpj88eew-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 13 Jun 2022 06:13:04 -0700 Received: from twshared17349.03.ash7.facebook.com (2620:10d:c085:208::f) by mail.thefacebook.com (2620:10d:c085:11d::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.28; Mon, 13 Jun 2022 06:13:03 -0700 Received: by devbig038.lla2.facebook.com (Postfix, from userid 572232) id 6388719A7608; Mon, 13 Jun 2022 06:12:56 -0700 (PDT) From: Dylan Yudaken To: , , CC: , Dylan Yudaken Subject: [PATCH liburing 3/4] add io_uring_buf_ring_init Date: Mon, 13 Jun 2022 06:12:52 -0700 Message-ID: <20220613131253.974205-4-dylany@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220613131253.974205-1-dylany@fb.com> References: <20220613131253.974205-1-dylany@fb.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-GUID: 152RaOOOIlUMQHZmFij-k3rZwHKZiT6R X-Proofpoint-ORIG-GUID: 152RaOOOIlUMQHZmFij-k3rZwHKZiT6R X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.874,Hydra:6.0.517,FMLib:17.11.64.514 definitions=2022-06-13_05,2022-06-13_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Kernel expects the tail to start at 0, so provide an API to init the ring appropriately. Signed-off-by: Dylan Yudaken --- man/io_uring_buf_ring_init.3 | 30 ++++++++++++++++++++++++++++++ man/io_uring_register_buf_ring.3 | 5 ++++- src/include/liburing.h | 5 +++++ test/send_recvmsg.c | 1 + 4 files changed, 40 insertions(+), 1 deletion(-) create mode 100644 man/io_uring_buf_ring_init.3 diff --git a/man/io_uring_buf_ring_init.3 b/man/io_uring_buf_ring_init.3 new file mode 100644 index 0000000..50cf69a --- /dev/null +++ b/man/io_uring_buf_ring_init.3 @@ -0,0 +1,30 @@ +.\" Copyright (C) 2022 Dylan Yudaken +.\" +.\" SPDX-License-Identifier: LGPL-2.0-or-later +.\" +.TH io_uring_buf_ring_init 3 "June 13, 2022" "liburing-2.2" "liburing Ma= nual" +.SH NAME +io_uring_buf_ring_init \- Initialise a buffer ring +.SH SYNOPSIS +.nf +.B #include +.PP +.BI "void io_uring_buf_ring_init(struct io_uring_buf_ring *" br ");" +.fi +.SH DESCRIPTION +.PP +.BR io_uring_buf_ring_init (3) +initialises +.IR br +so that it is ready to be used. It may be called after +.BR io_uring_register_buf_ring (3) +but must be called before the buffer ring is used in any other way. + +.SH RETURN VALUE +None + +.SH SEE ALSO +.BR io_uring_register_buf_ring (3), +.BR io_uring_buf_ring_add (3) +.BR io_uring_buf_ring_advance (3), +.BR io_uring_buf_ring_cq_advance (3) diff --git a/man/io_uring_register_buf_ring.3 b/man/io_uring_register_buf= _ring.3 index 9e0b53d..9e520bf 100644 --- a/man/io_uring_register_buf_ring.3 +++ b/man/io_uring_register_buf_ring.3 @@ -115,7 +115,9 @@ is the length of the buffer in bytes, and .I bid is the buffer ID that will be returned in the CQE once consumed. =20 -Reserved fields must not be touched. Applications may use +Reserved fields must not be touched. Applications must use +.BR io_uring_buf_ring_init (3) +to initialise the buffer ring. Applications may use .BR io_uring_buf_ring_add (3) and .BR io_uring_buf_ring_advance (3) @@ -131,6 +133,7 @@ On success returns 0. On failure it returns .BR -errno . .SH SEE ALSO +.BR io_uring_buf_ring_init (3), .BR io_uring_buf_ring_add (3), .BR io_uring_buf_ring_advance (3), .BR io_uring_buf_ring_cq_advance (3) diff --git a/src/include/liburing.h b/src/include/liburing.h index 9beef0b..c31ece2 100644 --- a/src/include/liburing.h +++ b/src/include/liburing.h @@ -1097,6 +1097,11 @@ static inline int io_uring_buf_ring_mask(__u32 rin= g_entries) return ring_entries - 1; } =20 +static inline void io_uring_buf_ring_init(struct io_uring_buf_ring *br) +{ + br->tail =3D 0; +} + /* * Assign 'buf' with the addr/len/buffer ID supplied */ diff --git a/test/send_recvmsg.c b/test/send_recvmsg.c index 6f18bae..cce6c45 100644 --- a/test/send_recvmsg.c +++ b/test/send_recvmsg.c @@ -199,6 +199,7 @@ static void *recv_fn(void *data) } =20 br =3D ptr; + io_uring_buf_ring_init(br); io_uring_buf_ring_add(br, buf, sizeof(buf), BUF_BID, io_uring_buf_ring_mask(1), 0); io_uring_buf_ring_advance(br, 1); --=20 2.30.2