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=-1.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIMWL_WL_MED 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 C5250C4321D for ; Fri, 17 Aug 2018 17:39:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A2172145D for ; Fri, 17 Aug 2018 17:39:04 +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="pJOCvp76" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7A2172145D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728072AbeHQUnS (ORCPT ); Fri, 17 Aug 2018 16:43:18 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:38405 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727612AbeHQUnR (ORCPT ); Fri, 17 Aug 2018 16:43:17 -0400 Received: by mail-pf1-f194.google.com with SMTP id x17-v6so3798284pfh.5 for ; Fri, 17 Aug 2018 10:39:02 -0700 (PDT) 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=/LlIEftYtD7GxPnLyw24zjttcZQ0OW8ZCqBx9AhaZ6A=; b=pJOCvp76qebF1rM/LHB8LfrjrXvgFx+iGw2gQU26qNW1Vw4Yo0tvJQDvI9Syj7M5TG 7pK7iXDOFBFNJn0v2vb+ALegIRgcgOlsoaA9scKcBAYP1cfLszVg7USruuow5Oq79olh pyduT482RgkC9t+kXJi/f8+U1qRwlroOJhYSgR/KmYXWVBMXCmh6eo1MghHpagRuGem1 axq60APnJsnjecVqrrCJcobhe2UGVvD2PReCUM1g9Gz61jH79YiHKu8yZAmmu07VNKQ6 ajwS7j/UKfUcCuv2Ml9MuOi0h9a0g2yxfVDbjxtjFU124+wqDy1PZ8SKD5vhH93z89QF Ft2A== 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=/LlIEftYtD7GxPnLyw24zjttcZQ0OW8ZCqBx9AhaZ6A=; b=CDOp2VvzglGIgBAklx8ZQSbquR91xmRUxZp/EsTsRj63KscfvBo6ndjNhmTs9sBn7q NQ2ndyn1ClOnbrLh+rUBU38z9pBiqrvTFK/eGd6i+NTbFEvNVqIQL5iQFmEk1AiuN6Jp JuugFyaY/BDV1ntvWQHE0v87v92jgaBOD4qiNQVY1zDULEpIUtobjALDbgU+kiWs4hXf ORAHk9QaCdHkBndWkdZ4Un+uoC9ZHqwCRvWmn13KPI1O3bjevRadzR5qCl/U/AIqvSCo Ol5BTctCd+kZlx+cE8seFOvZgzOR17hK5xAkR2lBF+MzQn2HgPeCazwKvGy0Kp2z2Orm tywQ== X-Gm-Message-State: AOUpUlFROn0HGRXUq+kAm6Oy7/LV4A/bD/ozcV/t/4uYCdlybVInob9i cIXvX5g6aTZ5BK/BktacrSfrww== X-Google-Smtp-Source: AA+uWPwqmNpfb4BNZIwwDA/GhMGgZ7WWnsjo9ZRvBUgvzsq1avO2g1yScQWq/swnGOB7EOW9wqFpWg== X-Received: by 2002:a62:3952:: with SMTP id g79-v6mr37536337pfa.133.1534527541935; Fri, 17 Aug 2018 10:39:01 -0700 (PDT) Received: from ?IPv6:2620:10d:c081:1133::1308? ([2620:10d:c090:180::1:7c2f]) by smtp.gmail.com with ESMTPSA id n24-v6sm4319169pfi.161.2018.08.17.10.38.59 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 17 Aug 2018 10:39:00 -0700 (PDT) Subject: Re: [PATCH] block, bfq: return nbytes and not zero from struct cftype .write() method To: "Maciej S. Szmigiero" Cc: Paolo Valente , linux-block@vger.kernel.org, linux-kernel , Arianna Avanzini References: <19c68f93-017d-cda1-632f-039ca3ca0158@kernel.dk> <1f2ca124-bb7c-d02c-07cd-4afe6a634ee6@maciej.szmigiero.name> From: Jens Axboe Message-ID: Date: Fri, 17 Aug 2018 11:38:57 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.0 MIME-Version: 1.0 In-Reply-To: <1f2ca124-bb7c-d02c-07cd-4afe6a634ee6@maciej.szmigiero.name> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/17/18 11:27 AM, Maciej S. Szmigiero wrote: > On 16.08.2018 21:11, Jens Axboe wrote: >> On 8/15/18 3:56 PM, Maciej S. Szmigiero wrote: >>> The value that struct cftype .write() method returns is then directly >>> returned to userspace as the value returned by write() syscall, so it >>> should be the number of bytes actually written (or consumed) and not zero. >>> >>> Returning zero from write() syscall makes programs like /bin/echo or bash >>> spin. >> >> Applied, thanks. > > Thanks. > >> Just a heads-up that gmail thinks your email is spam. > > Thanks for the information - it looks like gmail just doesn't like my > email server for some reason. This one came through fine, jfyi. -- Jens Axboe