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=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 90431C4338F for ; Sun, 8 Aug 2021 11:57:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6452E60C3E for ; Sun, 8 Aug 2021 11:57:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229977AbhHHL53 (ORCPT ); Sun, 8 Aug 2021 07:57:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59152 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229504AbhHHL52 (ORCPT ); Sun, 8 Aug 2021 07:57:28 -0400 Received: from mail-pj1-x1036.google.com (mail-pj1-x1036.google.com [IPv6:2607:f8b0:4864:20::1036]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 07106C061760 for ; Sun, 8 Aug 2021 04:57:08 -0700 (PDT) Received: by mail-pj1-x1036.google.com with SMTP id a8so23530454pjk.4 for ; Sun, 08 Aug 2021 04:57:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=D2+mieY3bULXhxBYhOHH9cxJN5BcoD7z2djMqbu8kx4=; b=JDaDEYCxL9i+1WAjUAcfFmPbXwPATX9s3K9FxuUYkLf9fZiMhGLRG5dj+Bk8J/X3RY ZfYPAvGQ/poSW4UcUD4RMCIne/iqWJ+Hx+Uqv2SwF8koor3V/G3QZje7tJNwr7xJJqmg zbdMXlQl2iYFzSYzNMPQi0feycF/u1z3lHAJ+CKcpFF3/WKTjY4GB9pqNrF3FBuL1LYi rozNVJjZ72DmEjO2LWgPS6sVw+ntmm9K3WFH5ftDIjcAlw2Zn9ny9WCBxUThekF83Vfr TauQWwVV2cg03Zco02eI0FFy5VKvBps2TS4XPr2CqSydG8N6vdAZMxNB7QhSLRsdUTud sWyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=D2+mieY3bULXhxBYhOHH9cxJN5BcoD7z2djMqbu8kx4=; b=Q+MXNnpfZy4FsK6L+WkCPtXHm3drdJ30527SWn6QioEkMtti28Aave4zA0TxIUJnyo kOD1UNU/ge3DMm0uo4kBj7NUWaoTIsBgAbcVZkL7tiJw+G7AZIXuN5kYlvDV9uIOl3GO thYchqkDfDKuzeGfUpccNdglDxTPQf9P9fhiYwYxpxkOEu48K5e33GNus3SNlfl2LadD CM1AQwN81+tvWT//3KISaQuQzRYg9G7f60BA7RL3bx4h03q6M1GcEivh7yOAWjnL+uZK VMlQ7ZHgRC0Apqv1sd5686bCltOrZ7P1WPVOErPbV8qCErvDhI3QuBhmDAJ9nRaLfEX3 qieA== X-Gm-Message-State: AOAM533tHGHHkDgezp0LS7FOmL+/KalARLrIVqb7wwqTzqoWlK6NSGDO h3YgsNyL5BjcLWvQvOeR6+A= X-Google-Smtp-Source: ABdhPJzN9XjW30TCgI7z21GNqu5IM+7+o2hmxaZpg0DiXxXigbe8FHQyMH9m9RXiE9D+Uah3d9TQTw== X-Received: by 2002:a17:90b:4c85:: with SMTP id my5mr31118491pjb.196.1628423828408; Sun, 08 Aug 2021 04:57:08 -0700 (PDT) Received: from realwakka ([59.12.165.26]) by smtp.gmail.com with ESMTPSA id d31sm19300916pgd.33.2021.08.08.04.57.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 08 Aug 2021 04:57:08 -0700 (PDT) Date: Sun, 8 Aug 2021 11:56:59 +0000 From: Sidong Yang To: Qu Wenruo Cc: linux-btrfs@vger.kernel.org Subject: Re: Simple question for newbie developer about qgroup Message-ID: <20210808115659.GA4081@realwakka> References: <20210807144736.GA2820@realwakka> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Sun, Aug 08, 2021 at 06:50:59AM +0800, Qu Wenruo wrote: > > > On 2021/8/7 下午10:47, Sidong Yang wrote: > > I read btrfs kernel source code about qgroup. I want to know about how > > works adding or deleting qgroups. and I read the function > > __del_qgroup_relation() in qgroup.c. > > > > This function checks whether dst is parent for src and store the result > > in variable named found. I think if the checks failed, the function > > needs to be failed or print warning message at least. Am I right? Or do > > you have other intentions? > > > > User can specify a non-exist parent/child pair, in that case we don't > need to print error message, as -ENOENT is enough to inform the user. Hi, Qu. Thanks for informing me. Now I continue to read the code. Thanks, Sidong > > Thanks, > Qu