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=-5.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 A4607C4BA13 for ; Wed, 26 Feb 2020 15:58:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7976524689 for ; Wed, 26 Feb 2020 15:58:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="UiNRpuEA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728978AbgBZP6u (ORCPT ); Wed, 26 Feb 2020 10:58:50 -0500 Received: from mail-il1-f194.google.com ([209.85.166.194]:36908 "EHLO mail-il1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728925AbgBZP6t (ORCPT ); Wed, 26 Feb 2020 10:58:49 -0500 Received: by mail-il1-f194.google.com with SMTP id v13so2805875iln.4 for ; Wed, 26 Feb 2020 07:58:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=u9tetjlW+tDcSR4yUipSGe6x9DTuqaQhNQPPb+CDQbE=; b=UiNRpuEAyN8wzG92Np9jVjC506dWwHMYkjEyzKxh0jutz8V45Vq1FROghvg18dwCEB 9oUfNe8K16yLnzBcB1t9D9mMaz+pyzc3qCo0ZHkmP2oyDY6aBKUasRX5DZQVsllhMFLG +ogzmF1ZCsUy0Q2RaduS5T9PR8WflpcaFPtLATuk9ewg9PWeGNH0a7WzgQGrrJABFIz5 R9o3Xww/Qh+alNFpI/nCPt9AONcRhYW7Q7MRgDgcREfTadNP1AgFW8s1wESfX3yF2g8u flAyUqL3697kmQXD4dBIUS/5yUOvOVmmE8NDr67HOcm7MbUozOKsk5e/flvbQZncolfL BiKg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=u9tetjlW+tDcSR4yUipSGe6x9DTuqaQhNQPPb+CDQbE=; b=FkM8xLfi8/mnaAV7bcTArcyxoxR/gT6oQRtY02gkixM3ueLb1BSA6xpbOxUDSdr2pv Go63vqI2pHqFzilUom2OafkOMXWC4reRg4IrPv7PF4hKY0yS6ck5oazqBYR19gPbgcsI dXNwhKCAHFPjy4vlPR+AMxpeaK6UWJ229QUnd20bB1nzoqQ1blADuC9JVA2UudjoiuW9 5ln/NjjO0+nuetzVIN388MBHEdMfrQd2MnR9PwOUFidCk5YSM10UPAkiaakcW7cRt8/b eVtXeEifEQA9A0PhOJzxANnQ28YFrHO+Q7o7jp1wOsLS9J7Ysu5x9BQzSnXQhpdYydTY 1swA== X-Gm-Message-State: APjAAAU/jJVrumHupErabiwK2VOsAgVpEiCKaTADwLAws7SiWyzpYHY4 ZPYCHaVVR05314b79Jq0F9Ll5MKNFnA97w== X-Google-Smtp-Source: APXvYqxJiIOjf+VwFA5v3wJ61HRm5iIcx79nUhEJCQKxmcNVQnBbnRH4KSjEAeR6CQDwNeq7xsZTDQ== X-Received: by 2002:a92:91c7:: with SMTP id e68mr6025346ill.161.1582732727744; Wed, 26 Feb 2020 07:58:47 -0800 (PST) Received: from [192.168.1.159] ([65.144.74.34]) by smtp.gmail.com with ESMTPSA id s69sm767693ilc.67.2020.02.26.07.58.46 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 26 Feb 2020 07:58:47 -0800 (PST) Subject: Re: [PATCH 1/4] io_uring: add IORING_OP_READ{WRITE}V_PI cmd To: Christoph Hellwig Cc: Bob Liu , linux-block@vger.kernel.org, martin.petersen@oracle.com, linux-fsdevel@vger.kernel.org, darrick.wong@oracle.com, io-uring@vger.kernel.org References: <20200226083719.4389-1-bob.liu@oracle.com> <20200226083719.4389-2-bob.liu@oracle.com> <6e466774-4dc5-861c-58b5-f0cc728bacff@kernel.dk> <20200226155728.GA32543@infradead.org> From: Jens Axboe Message-ID: Date: Wed, 26 Feb 2020 08:58:46 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200226155728.GA32543@infradead.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 2/26/20 8:57 AM, Christoph Hellwig wrote: > On Wed, Feb 26, 2020 at 07:24:06AM -0700, Jens Axboe wrote: >> On 2/26/20 1:37 AM, Bob Liu wrote: >>> diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h >>> index a3300e1..98fa3f1 100644 >>> --- a/include/uapi/linux/io_uring.h >>> +++ b/include/uapi/linux/io_uring.h >>> @@ -62,6 +62,8 @@ enum { >>> IORING_OP_NOP, >>> IORING_OP_READV, >>> IORING_OP_WRITEV, >>> + IORING_OP_READV_PI, >>> + IORING_OP_WRITEV_PI, >>> IORING_OP_FSYNC, >>> IORING_OP_READ_FIXED, >>> IORING_OP_WRITE_FIXED, >> >> So this one renumbers everything past IORING_OP_WRITEV, breaking the >> ABI in a very bad way. I'm guessing that was entirely unintentional? >> Any new command must go at the end of the list. >> >> You're also not updating io_op_defs[] with the two new commands, >> which means it won't compile at all. I'm guessing you tested this on >> an older version of the kernel which didn't have io_op_defs[]? > > And the real question is why we need ops insted of just a flag and > using previously reserved fields for the PI pointer. Yeah, should probably be a RWF_ flag instead, and a 64-bit SQE field for the PI data. The 'last iovec is PI' is kind of icky. -- Jens Axboe